1 // arm.cc -- arm target support for gold.
3 // Copyright 2009, 2010 Free Software Foundation, Inc.
4 // Written by Doug Kwan <dougkwan@google.com> based on the i386 code
5 // by Ian Lance Taylor <iant@google.com>.
6 // This file also contains borrowed and adapted code from
9 // This file is part of gold.
11 // This program is free software; you can redistribute it and/or modify
12 // it under the terms of the GNU General Public License as published by
13 // the Free Software Foundation; either version 3 of the License, or
14 // (at your option) any later version.
16 // This program is distributed in the hope that it will be useful,
17 // but WITHOUT ANY WARRANTY; without even the implied warranty of
18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 // GNU General Public License for more details.
21 // You should have received a copy of the GNU General Public License
22 // along with this program; if not, write to the Free Software
23 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
24 // MA 02110-1301, USA.
38 #include "parameters.h"
45 #include "copy-relocs.h"
47 #include "target-reloc.h"
48 #include "target-select.h"
52 #include "attributes.h"
53 #include "arm-reloc-property.h"
60 template<bool big_endian
>
61 class Output_data_plt_arm
;
63 template<bool big_endian
>
66 template<bool big_endian
>
67 class Arm_input_section
;
69 class Arm_exidx_cantunwind
;
71 class Arm_exidx_merged_section
;
73 class Arm_exidx_fixup
;
75 template<bool big_endian
>
76 class Arm_output_section
;
78 class Arm_exidx_input_section
;
80 template<bool big_endian
>
83 template<bool big_endian
>
87 typedef elfcpp::Elf_types
<32>::Elf_Addr Arm_address
;
89 // Maximum branch offsets for ARM, THUMB and THUMB2.
90 const int32_t ARM_MAX_FWD_BRANCH_OFFSET
= ((((1 << 23) - 1) << 2) + 8);
91 const int32_t ARM_MAX_BWD_BRANCH_OFFSET
= ((-((1 << 23) << 2)) + 8);
92 const int32_t THM_MAX_FWD_BRANCH_OFFSET
= ((1 << 22) -2 + 4);
93 const int32_t THM_MAX_BWD_BRANCH_OFFSET
= (-(1 << 22) + 4);
94 const int32_t THM2_MAX_FWD_BRANCH_OFFSET
= (((1 << 24) - 2) + 4);
95 const int32_t THM2_MAX_BWD_BRANCH_OFFSET
= (-(1 << 24) + 4);
97 // The arm target class.
99 // This is a very simple port of gold for ARM-EABI. It is intended for
100 // supporting Android only for the time being.
103 // - Implement all static relocation types documented in arm-reloc.def.
104 // - Make PLTs more flexible for different architecture features like
106 // There are probably a lot more.
108 // Ideally we would like to avoid using global variables but this is used
109 // very in many places and sometimes in loops. If we use a function
110 // returning a static instance of Arm_reloc_property_table, it will very
111 // slow in an threaded environment since the static instance needs to be
112 // locked. The pointer is below initialized in the
113 // Target::do_select_as_default_target() hook so that we do not spend time
114 // building the table if we are not linking ARM objects.
116 // An alternative is to to process the information in arm-reloc.def in
117 // compilation time and generate a representation of it in PODs only. That
118 // way we can avoid initialization when the linker starts.
120 Arm_reloc_property_table
*arm_reloc_property_table
= NULL
;
122 // Instruction template class. This class is similar to the insn_sequence
123 // struct in bfd/elf32-arm.c.
128 // Types of instruction templates.
132 // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
133 // templates with class-specific semantics. Currently this is used
134 // only by the Cortex_a8_stub class for handling condition codes in
135 // conditional branches.
136 THUMB16_SPECIAL_TYPE
,
142 // Factory methods to create instruction templates in different formats.
144 static const Insn_template
145 thumb16_insn(uint32_t data
)
146 { return Insn_template(data
, THUMB16_TYPE
, elfcpp::R_ARM_NONE
, 0); }
148 // A Thumb conditional branch, in which the proper condition is inserted
149 // when we build the stub.
150 static const Insn_template
151 thumb16_bcond_insn(uint32_t data
)
152 { return Insn_template(data
, THUMB16_SPECIAL_TYPE
, elfcpp::R_ARM_NONE
, 1); }
154 static const Insn_template
155 thumb32_insn(uint32_t data
)
156 { return Insn_template(data
, THUMB32_TYPE
, elfcpp::R_ARM_NONE
, 0); }
158 static const Insn_template
159 thumb32_b_insn(uint32_t data
, int reloc_addend
)
161 return Insn_template(data
, THUMB32_TYPE
, elfcpp::R_ARM_THM_JUMP24
,
165 static const Insn_template
166 arm_insn(uint32_t data
)
167 { return Insn_template(data
, ARM_TYPE
, elfcpp::R_ARM_NONE
, 0); }
169 static const Insn_template
170 arm_rel_insn(unsigned data
, int reloc_addend
)
171 { return Insn_template(data
, ARM_TYPE
, elfcpp::R_ARM_JUMP24
, reloc_addend
); }
173 static const Insn_template
174 data_word(unsigned data
, unsigned int r_type
, int reloc_addend
)
175 { return Insn_template(data
, DATA_TYPE
, r_type
, reloc_addend
); }
177 // Accessors. This class is used for read-only objects so no modifiers
182 { return this->data_
; }
184 // Return the instruction sequence type of this.
187 { return this->type_
; }
189 // Return the ARM relocation type of this.
192 { return this->r_type_
; }
196 { return this->reloc_addend_
; }
198 // Return size of instruction template in bytes.
202 // Return byte-alignment of instruction template.
207 // We make the constructor private to ensure that only the factory
210 Insn_template(unsigned data
, Type type
, unsigned int r_type
, int reloc_addend
)
211 : data_(data
), type_(type
), r_type_(r_type
), reloc_addend_(reloc_addend
)
214 // Instruction specific data. This is used to store information like
215 // some of the instruction bits.
217 // Instruction template type.
219 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
220 unsigned int r_type_
;
221 // Relocation addend.
222 int32_t reloc_addend_
;
225 // Macro for generating code to stub types. One entry per long/short
229 DEF_STUB(long_branch_any_any) \
230 DEF_STUB(long_branch_v4t_arm_thumb) \
231 DEF_STUB(long_branch_thumb_only) \
232 DEF_STUB(long_branch_v4t_thumb_thumb) \
233 DEF_STUB(long_branch_v4t_thumb_arm) \
234 DEF_STUB(short_branch_v4t_thumb_arm) \
235 DEF_STUB(long_branch_any_arm_pic) \
236 DEF_STUB(long_branch_any_thumb_pic) \
237 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
238 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
239 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
240 DEF_STUB(long_branch_thumb_only_pic) \
241 DEF_STUB(a8_veneer_b_cond) \
242 DEF_STUB(a8_veneer_b) \
243 DEF_STUB(a8_veneer_bl) \
244 DEF_STUB(a8_veneer_blx) \
245 DEF_STUB(v4_veneer_bx)
249 #define DEF_STUB(x) arm_stub_##x,
255 // First reloc stub type.
256 arm_stub_reloc_first
= arm_stub_long_branch_any_any
,
257 // Last reloc stub type.
258 arm_stub_reloc_last
= arm_stub_long_branch_thumb_only_pic
,
260 // First Cortex-A8 stub type.
261 arm_stub_cortex_a8_first
= arm_stub_a8_veneer_b_cond
,
262 // Last Cortex-A8 stub type.
263 arm_stub_cortex_a8_last
= arm_stub_a8_veneer_blx
,
266 arm_stub_type_last
= arm_stub_v4_veneer_bx
270 // Stub template class. Templates are meant to be read-only objects.
271 // A stub template for a stub type contains all read-only attributes
272 // common to all stubs of the same type.
277 Stub_template(Stub_type
, const Insn_template
*, size_t);
285 { return this->type_
; }
287 // Return an array of instruction templates.
290 { return this->insns_
; }
292 // Return size of template in number of instructions.
295 { return this->insn_count_
; }
297 // Return size of template in bytes.
300 { return this->size_
; }
302 // Return alignment of the stub template.
305 { return this->alignment_
; }
307 // Return whether entry point is in thumb mode.
309 entry_in_thumb_mode() const
310 { return this->entry_in_thumb_mode_
; }
312 // Return number of relocations in this template.
315 { return this->relocs_
.size(); }
317 // Return index of the I-th instruction with relocation.
319 reloc_insn_index(size_t i
) const
321 gold_assert(i
< this->relocs_
.size());
322 return this->relocs_
[i
].first
;
325 // Return the offset of the I-th instruction with relocation from the
326 // beginning of the stub.
328 reloc_offset(size_t i
) const
330 gold_assert(i
< this->relocs_
.size());
331 return this->relocs_
[i
].second
;
335 // This contains information about an instruction template with a relocation
336 // and its offset from start of stub.
337 typedef std::pair
<size_t, section_size_type
> Reloc
;
339 // A Stub_template may not be copied. We want to share templates as much
341 Stub_template(const Stub_template
&);
342 Stub_template
& operator=(const Stub_template
&);
346 // Points to an array of Insn_templates.
347 const Insn_template
* insns_
;
348 // Number of Insn_templates in insns_[].
350 // Size of templated instructions in bytes.
352 // Alignment of templated instructions.
354 // Flag to indicate if entry is in thumb mode.
355 bool entry_in_thumb_mode_
;
356 // A table of reloc instruction indices and offsets. We can find these by
357 // looking at the instruction templates but we pre-compute and then stash
358 // them here for speed.
359 std::vector
<Reloc
> relocs_
;
363 // A class for code stubs. This is a base class for different type of
364 // stubs used in the ARM target.
370 static const section_offset_type invalid_offset
=
371 static_cast<section_offset_type
>(-1);
374 Stub(const Stub_template
* stub_template
)
375 : stub_template_(stub_template
), offset_(invalid_offset
)
382 // Return the stub template.
384 stub_template() const
385 { return this->stub_template_
; }
387 // Return offset of code stub from beginning of its containing stub table.
391 gold_assert(this->offset_
!= invalid_offset
);
392 return this->offset_
;
395 // Set offset of code stub from beginning of its containing stub table.
397 set_offset(section_offset_type offset
)
398 { this->offset_
= offset
; }
400 // Return the relocation target address of the i-th relocation in the
401 // stub. This must be defined in a child class.
403 reloc_target(size_t i
)
404 { return this->do_reloc_target(i
); }
406 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
408 write(unsigned char* view
, section_size_type view_size
, bool big_endian
)
409 { this->do_write(view
, view_size
, big_endian
); }
411 // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
412 // for the i-th instruction.
414 thumb16_special(size_t i
)
415 { return this->do_thumb16_special(i
); }
418 // This must be defined in the child class.
420 do_reloc_target(size_t) = 0;
422 // This may be overridden in the child class.
424 do_write(unsigned char* view
, section_size_type view_size
, bool big_endian
)
427 this->do_fixed_endian_write
<true>(view
, view_size
);
429 this->do_fixed_endian_write
<false>(view
, view_size
);
432 // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
433 // instruction template.
435 do_thumb16_special(size_t)
436 { gold_unreachable(); }
439 // A template to implement do_write.
440 template<bool big_endian
>
442 do_fixed_endian_write(unsigned char*, section_size_type
);
445 const Stub_template
* stub_template_
;
446 // Offset within the section of containing this stub.
447 section_offset_type offset_
;
450 // Reloc stub class. These are stubs we use to fix up relocation because
451 // of limited branch ranges.
453 class Reloc_stub
: public Stub
456 static const unsigned int invalid_index
= static_cast<unsigned int>(-1);
457 // We assume we never jump to this address.
458 static const Arm_address invalid_address
= static_cast<Arm_address
>(-1);
460 // Return destination address.
462 destination_address() const
464 gold_assert(this->destination_address_
!= this->invalid_address
);
465 return this->destination_address_
;
468 // Set destination address.
470 set_destination_address(Arm_address address
)
472 gold_assert(address
!= this->invalid_address
);
473 this->destination_address_
= address
;
476 // Reset destination address.
478 reset_destination_address()
479 { this->destination_address_
= this->invalid_address
; }
481 // Determine stub type for a branch of a relocation of R_TYPE going
482 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
483 // the branch target is a thumb instruction. TARGET is used for look
484 // up ARM-specific linker settings.
486 stub_type_for_reloc(unsigned int r_type
, Arm_address branch_address
,
487 Arm_address branch_target
, bool target_is_thumb
);
489 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
490 // and an addend. Since we treat global and local symbol differently, we
491 // use a Symbol object for a global symbol and a object-index pair for
496 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
497 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
498 // and R_SYM must not be invalid_index.
499 Key(Stub_type stub_type
, const Symbol
* symbol
, const Relobj
* relobj
,
500 unsigned int r_sym
, int32_t addend
)
501 : stub_type_(stub_type
), addend_(addend
)
505 this->r_sym_
= Reloc_stub::invalid_index
;
506 this->u_
.symbol
= symbol
;
510 gold_assert(relobj
!= NULL
&& r_sym
!= invalid_index
);
511 this->r_sym_
= r_sym
;
512 this->u_
.relobj
= relobj
;
519 // Accessors: Keys are meant to be read-only object so no modifiers are
525 { return this->stub_type_
; }
527 // Return the local symbol index or invalid_index.
530 { return this->r_sym_
; }
532 // Return the symbol if there is one.
535 { return this->r_sym_
== invalid_index
? this->u_
.symbol
: NULL
; }
537 // Return the relobj if there is one.
540 { return this->r_sym_
!= invalid_index
? this->u_
.relobj
: NULL
; }
542 // Whether this equals to another key k.
544 eq(const Key
& k
) const
546 return ((this->stub_type_
== k
.stub_type_
)
547 && (this->r_sym_
== k
.r_sym_
)
548 && ((this->r_sym_
!= Reloc_stub::invalid_index
)
549 ? (this->u_
.relobj
== k
.u_
.relobj
)
550 : (this->u_
.symbol
== k
.u_
.symbol
))
551 && (this->addend_
== k
.addend_
));
554 // Return a hash value.
558 return (this->stub_type_
560 ^ gold::string_hash
<char>(
561 (this->r_sym_
!= Reloc_stub::invalid_index
)
562 ? this->u_
.relobj
->name().c_str()
563 : this->u_
.symbol
->name())
567 // Functors for STL associative containers.
571 operator()(const Key
& k
) const
572 { return k
.hash_value(); }
578 operator()(const Key
& k1
, const Key
& k2
) const
579 { return k1
.eq(k2
); }
582 // Name of key. This is mainly for debugging.
588 Stub_type stub_type_
;
589 // If this is a local symbol, this is the index in the defining object.
590 // Otherwise, it is invalid_index for a global symbol.
592 // If r_sym_ is invalid index. This points to a global symbol.
593 // Otherwise, this points a relobj. We used the unsized and target
594 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
595 // Arm_relobj. This is done to avoid making the stub class a template
596 // as most of the stub machinery is endianity-neutral. However, it
597 // may require a bit of casting done by users of this class.
600 const Symbol
* symbol
;
601 const Relobj
* relobj
;
603 // Addend associated with a reloc.
608 // Reloc_stubs are created via a stub factory. So these are protected.
609 Reloc_stub(const Stub_template
* stub_template
)
610 : Stub(stub_template
), destination_address_(invalid_address
)
616 friend class Stub_factory
;
618 // Return the relocation target address of the i-th relocation in the
621 do_reloc_target(size_t i
)
623 // All reloc stub have only one relocation.
625 return this->destination_address_
;
629 // Address of destination.
630 Arm_address destination_address_
;
633 // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
634 // THUMB branch that meets the following conditions:
636 // 1. The branch straddles across a page boundary. i.e. lower 12-bit of
637 // branch address is 0xffe.
638 // 2. The branch target address is in the same page as the first word of the
640 // 3. The branch follows a 32-bit instruction which is not a branch.
642 // To do the fix up, we need to store the address of the branch instruction
643 // and its target at least. We also need to store the original branch
644 // instruction bits for the condition code in a conditional branch. The
645 // condition code is used in a special instruction template. We also want
646 // to identify input sections needing Cortex-A8 workaround quickly. We store
647 // extra information about object and section index of the code section
648 // containing a branch being fixed up. The information is used to mark
649 // the code section when we finalize the Cortex-A8 stubs.
652 class Cortex_a8_stub
: public Stub
658 // Return the object of the code section containing the branch being fixed
662 { return this->relobj_
; }
664 // Return the section index of the code section containing the branch being
668 { return this->shndx_
; }
670 // Return the source address of stub. This is the address of the original
671 // branch instruction. LSB is 1 always set to indicate that it is a THUMB
674 source_address() const
675 { return this->source_address_
; }
677 // Return the destination address of the stub. This is the branch taken
678 // address of the original branch instruction. LSB is 1 if it is a THUMB
679 // instruction address.
681 destination_address() const
682 { return this->destination_address_
; }
684 // Return the instruction being fixed up.
686 original_insn() const
687 { return this->original_insn_
; }
690 // Cortex_a8_stubs are created via a stub factory. So these are protected.
691 Cortex_a8_stub(const Stub_template
* stub_template
, Relobj
* relobj
,
692 unsigned int shndx
, Arm_address source_address
,
693 Arm_address destination_address
, uint32_t original_insn
)
694 : Stub(stub_template
), relobj_(relobj
), shndx_(shndx
),
695 source_address_(source_address
| 1U),
696 destination_address_(destination_address
),
697 original_insn_(original_insn
)
700 friend class Stub_factory
;
702 // Return the relocation target address of the i-th relocation in the
705 do_reloc_target(size_t i
)
707 if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond
)
709 // The conditional branch veneer has two relocations.
711 return i
== 0 ? this->source_address_
+ 4 : this->destination_address_
;
715 // All other Cortex-A8 stubs have only one relocation.
717 return this->destination_address_
;
721 // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
723 do_thumb16_special(size_t);
726 // Object of the code section containing the branch being fixed up.
728 // Section index of the code section containing the branch begin fixed up.
730 // Source address of original branch.
731 Arm_address source_address_
;
732 // Destination address of the original branch.
733 Arm_address destination_address_
;
734 // Original branch instruction. This is needed for copying the condition
735 // code from a condition branch to its stub.
736 uint32_t original_insn_
;
739 // ARMv4 BX Rx branch relocation stub class.
740 class Arm_v4bx_stub
: public Stub
746 // Return the associated register.
749 { return this->reg_
; }
752 // Arm V4BX stubs are created via a stub factory. So these are protected.
753 Arm_v4bx_stub(const Stub_template
* stub_template
, const uint32_t reg
)
754 : Stub(stub_template
), reg_(reg
)
757 friend class Stub_factory
;
759 // Return the relocation target address of the i-th relocation in the
762 do_reloc_target(size_t)
763 { gold_unreachable(); }
765 // This may be overridden in the child class.
767 do_write(unsigned char* view
, section_size_type view_size
, bool big_endian
)
770 this->do_fixed_endian_v4bx_write
<true>(view
, view_size
);
772 this->do_fixed_endian_v4bx_write
<false>(view
, view_size
);
776 // A template to implement do_write.
777 template<bool big_endian
>
779 do_fixed_endian_v4bx_write(unsigned char* view
, section_size_type
)
781 const Insn_template
* insns
= this->stub_template()->insns();
782 elfcpp::Swap
<32, big_endian
>::writeval(view
,
784 + (this->reg_
<< 16)));
785 view
+= insns
[0].size();
786 elfcpp::Swap
<32, big_endian
>::writeval(view
,
787 (insns
[1].data() + this->reg_
));
788 view
+= insns
[1].size();
789 elfcpp::Swap
<32, big_endian
>::writeval(view
,
790 (insns
[2].data() + this->reg_
));
793 // A register index (r0-r14), which is associated with the stub.
797 // Stub factory class.
802 // Return the unique instance of this class.
803 static const Stub_factory
&
806 static Stub_factory singleton
;
810 // Make a relocation stub.
812 make_reloc_stub(Stub_type stub_type
) const
814 gold_assert(stub_type
>= arm_stub_reloc_first
815 && stub_type
<= arm_stub_reloc_last
);
816 return new Reloc_stub(this->stub_templates_
[stub_type
]);
819 // Make a Cortex-A8 stub.
821 make_cortex_a8_stub(Stub_type stub_type
, Relobj
* relobj
, unsigned int shndx
,
822 Arm_address source
, Arm_address destination
,
823 uint32_t original_insn
) const
825 gold_assert(stub_type
>= arm_stub_cortex_a8_first
826 && stub_type
<= arm_stub_cortex_a8_last
);
827 return new Cortex_a8_stub(this->stub_templates_
[stub_type
], relobj
, shndx
,
828 source
, destination
, original_insn
);
831 // Make an ARM V4BX relocation stub.
832 // This method creates a stub from the arm_stub_v4_veneer_bx template only.
834 make_arm_v4bx_stub(uint32_t reg
) const
836 gold_assert(reg
< 0xf);
837 return new Arm_v4bx_stub(this->stub_templates_
[arm_stub_v4_veneer_bx
],
842 // Constructor and destructor are protected since we only return a single
843 // instance created in Stub_factory::get_instance().
847 // A Stub_factory may not be copied since it is a singleton.
848 Stub_factory(const Stub_factory
&);
849 Stub_factory
& operator=(Stub_factory
&);
851 // Stub templates. These are initialized in the constructor.
852 const Stub_template
* stub_templates_
[arm_stub_type_last
+1];
855 // A class to hold stubs for the ARM target.
857 template<bool big_endian
>
858 class Stub_table
: public Output_data
861 Stub_table(Arm_input_section
<big_endian
>* owner
)
862 : Output_data(), owner_(owner
), reloc_stubs_(), cortex_a8_stubs_(),
863 arm_v4bx_stubs_(0xf), prev_data_size_(0), prev_addralign_(1)
869 // Owner of this stub table.
870 Arm_input_section
<big_endian
>*
872 { return this->owner_
; }
874 // Whether this stub table is empty.
878 return (this->reloc_stubs_
.empty()
879 && this->cortex_a8_stubs_
.empty()
880 && this->arm_v4bx_stubs_
.empty());
883 // Return the current data size.
885 current_data_size() const
886 { return this->current_data_size_for_child(); }
888 // Add a STUB with using KEY. Caller is reponsible for avoid adding
889 // if already a STUB with the same key has been added.
891 add_reloc_stub(Reloc_stub
* stub
, const Reloc_stub::Key
& key
)
893 const Stub_template
* stub_template
= stub
->stub_template();
894 gold_assert(stub_template
->type() == key
.stub_type());
895 this->reloc_stubs_
[key
] = stub
;
898 // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
899 // Caller is reponsible for avoid adding if already a STUB with the same
900 // address has been added.
902 add_cortex_a8_stub(Arm_address address
, Cortex_a8_stub
* stub
)
904 std::pair
<Arm_address
, Cortex_a8_stub
*> value(address
, stub
);
905 this->cortex_a8_stubs_
.insert(value
);
908 // Add an ARM V4BX relocation stub. A register index will be retrieved
911 add_arm_v4bx_stub(Arm_v4bx_stub
* stub
)
913 gold_assert(stub
!= NULL
&& this->arm_v4bx_stubs_
[stub
->reg()] == NULL
);
914 this->arm_v4bx_stubs_
[stub
->reg()] = stub
;
917 // Remove all Cortex-A8 stubs.
919 remove_all_cortex_a8_stubs();
921 // Look up a relocation stub using KEY. Return NULL if there is none.
923 find_reloc_stub(const Reloc_stub::Key
& key
) const
925 typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.find(key
);
926 return (p
!= this->reloc_stubs_
.end()) ? p
->second
: NULL
;
929 // Look up an arm v4bx relocation stub using the register index.
930 // Return NULL if there is none.
932 find_arm_v4bx_stub(const uint32_t reg
) const
934 gold_assert(reg
< 0xf);
935 return this->arm_v4bx_stubs_
[reg
];
938 // Relocate stubs in this stub table.
940 relocate_stubs(const Relocate_info
<32, big_endian
>*,
941 Target_arm
<big_endian
>*, Output_section
*,
942 unsigned char*, Arm_address
, section_size_type
);
944 // Update data size and alignment at the end of a relaxation pass. Return
945 // true if either data size or alignment is different from that of the
946 // previous relaxation pass.
948 update_data_size_and_addralign();
950 // Finalize stubs. Set the offsets of all stubs and mark input sections
951 // needing the Cortex-A8 workaround.
955 // Apply Cortex-A8 workaround to an address range.
957 apply_cortex_a8_workaround_to_address_range(Target_arm
<big_endian
>*,
958 unsigned char*, Arm_address
,
962 // Write out section contents.
964 do_write(Output_file
*);
966 // Return the required alignment.
969 { return this->prev_addralign_
; }
971 // Reset address and file offset.
973 do_reset_address_and_file_offset()
974 { this->set_current_data_size_for_child(this->prev_data_size_
); }
976 // Set final data size.
978 set_final_data_size()
979 { this->set_data_size(this->current_data_size()); }
982 // Relocate one stub.
984 relocate_stub(Stub
*, const Relocate_info
<32, big_endian
>*,
985 Target_arm
<big_endian
>*, Output_section
*,
986 unsigned char*, Arm_address
, section_size_type
);
988 // Unordered map of relocation stubs.
990 Unordered_map
<Reloc_stub::Key
, Reloc_stub
*, Reloc_stub::Key::hash
,
991 Reloc_stub::Key::equal_to
>
994 // List of Cortex-A8 stubs ordered by addresses of branches being
995 // fixed up in output.
996 typedef std::map
<Arm_address
, Cortex_a8_stub
*> Cortex_a8_stub_list
;
997 // List of Arm V4BX relocation stubs ordered by associated registers.
998 typedef std::vector
<Arm_v4bx_stub
*> Arm_v4bx_stub_list
;
1000 // Owner of this stub table.
1001 Arm_input_section
<big_endian
>* owner_
;
1002 // The relocation stubs.
1003 Reloc_stub_map reloc_stubs_
;
1004 // The cortex_a8_stubs.
1005 Cortex_a8_stub_list cortex_a8_stubs_
;
1006 // The Arm V4BX relocation stubs.
1007 Arm_v4bx_stub_list arm_v4bx_stubs_
;
1008 // data size of this in the previous pass.
1009 off_t prev_data_size_
;
1010 // address alignment of this in the previous pass.
1011 uint64_t prev_addralign_
;
1014 // Arm_exidx_cantunwind class. This represents an EXIDX_CANTUNWIND entry
1015 // we add to the end of an EXIDX input section that goes into the output.
1017 class Arm_exidx_cantunwind
: public Output_section_data
1020 Arm_exidx_cantunwind(Relobj
* relobj
, unsigned int shndx
)
1021 : Output_section_data(8, 4, true), relobj_(relobj
), shndx_(shndx
)
1024 // Return the object containing the section pointed by this.
1027 { return this->relobj_
; }
1029 // Return the section index of the section pointed by this.
1032 { return this->shndx_
; }
1036 do_write(Output_file
* of
)
1038 if (parameters
->target().is_big_endian())
1039 this->do_fixed_endian_write
<true>(of
);
1041 this->do_fixed_endian_write
<false>(of
);
1045 // Implement do_write for a given endianity.
1046 template<bool big_endian
>
1048 do_fixed_endian_write(Output_file
*);
1050 // The object containing the section pointed by this.
1052 // The section index of the section pointed by this.
1053 unsigned int shndx_
;
1056 // During EXIDX coverage fix-up, we compact an EXIDX section. The
1057 // Offset map is used to map input section offset within the EXIDX section
1058 // to the output offset from the start of this EXIDX section.
1060 typedef std::map
<section_offset_type
, section_offset_type
>
1061 Arm_exidx_section_offset_map
;
1063 // Arm_exidx_merged_section class. This represents an EXIDX input section
1064 // with some of its entries merged.
1066 class Arm_exidx_merged_section
: public Output_relaxed_input_section
1069 // Constructor for Arm_exidx_merged_section.
1070 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
1071 // SECTION_OFFSET_MAP points to a section offset map describing how
1072 // parts of the input section are mapped to output. DELETED_BYTES is
1073 // the number of bytes deleted from the EXIDX input section.
1074 Arm_exidx_merged_section(
1075 const Arm_exidx_input_section
& exidx_input_section
,
1076 const Arm_exidx_section_offset_map
& section_offset_map
,
1077 uint32_t deleted_bytes
);
1079 // Return the original EXIDX input section.
1080 const Arm_exidx_input_section
&
1081 exidx_input_section() const
1082 { return this->exidx_input_section_
; }
1084 // Return the section offset map.
1085 const Arm_exidx_section_offset_map
&
1086 section_offset_map() const
1087 { return this->section_offset_map_
; }
1090 // Write merged section into file OF.
1092 do_write(Output_file
* of
);
1095 do_output_offset(const Relobj
*, unsigned int, section_offset_type
,
1096 section_offset_type
*) const;
1099 // Original EXIDX input section.
1100 const Arm_exidx_input_section
& exidx_input_section_
;
1101 // Section offset map.
1102 const Arm_exidx_section_offset_map
& section_offset_map_
;
1105 // A class to wrap an ordinary input section containing executable code.
1107 template<bool big_endian
>
1108 class Arm_input_section
: public Output_relaxed_input_section
1111 Arm_input_section(Relobj
* relobj
, unsigned int shndx
)
1112 : Output_relaxed_input_section(relobj
, shndx
, 1),
1113 original_addralign_(1), original_size_(0), stub_table_(NULL
)
1116 ~Arm_input_section()
1123 // Whether this is a stub table owner.
1125 is_stub_table_owner() const
1126 { return this->stub_table_
!= NULL
&& this->stub_table_
->owner() == this; }
1128 // Return the stub table.
1129 Stub_table
<big_endian
>*
1131 { return this->stub_table_
; }
1133 // Set the stub_table.
1135 set_stub_table(Stub_table
<big_endian
>* stub_table
)
1136 { this->stub_table_
= stub_table
; }
1138 // Downcast a base pointer to an Arm_input_section pointer. This is
1139 // not type-safe but we only use Arm_input_section not the base class.
1140 static Arm_input_section
<big_endian
>*
1141 as_arm_input_section(Output_relaxed_input_section
* poris
)
1142 { return static_cast<Arm_input_section
<big_endian
>*>(poris
); }
1145 // Write data to output file.
1147 do_write(Output_file
*);
1149 // Return required alignment of this.
1151 do_addralign() const
1153 if (this->is_stub_table_owner())
1154 return std::max(this->stub_table_
->addralign(),
1155 this->original_addralign_
);
1157 return this->original_addralign_
;
1160 // Finalize data size.
1162 set_final_data_size();
1164 // Reset address and file offset.
1166 do_reset_address_and_file_offset();
1170 do_output_offset(const Relobj
* object
, unsigned int shndx
,
1171 section_offset_type offset
,
1172 section_offset_type
* poutput
) const
1174 if ((object
== this->relobj())
1175 && (shndx
== this->shndx())
1177 && (convert_types
<uint64_t, section_offset_type
>(offset
)
1178 <= this->original_size_
))
1188 // Copying is not allowed.
1189 Arm_input_section(const Arm_input_section
&);
1190 Arm_input_section
& operator=(const Arm_input_section
&);
1192 // Address alignment of the original input section.
1193 uint64_t original_addralign_
;
1194 // Section size of the original input section.
1195 uint64_t original_size_
;
1197 Stub_table
<big_endian
>* stub_table_
;
1200 // Arm_exidx_fixup class. This is used to define a number of methods
1201 // and keep states for fixing up EXIDX coverage.
1203 class Arm_exidx_fixup
1206 Arm_exidx_fixup(Output_section
* exidx_output_section
)
1207 : exidx_output_section_(exidx_output_section
), last_unwind_type_(UT_NONE
),
1208 last_inlined_entry_(0), last_input_section_(NULL
),
1209 section_offset_map_(NULL
), first_output_text_section_(NULL
)
1213 { delete this->section_offset_map_
; }
1215 // Process an EXIDX section for entry merging. Return number of bytes to
1216 // be deleted in output. If parts of the input EXIDX section are merged
1217 // a heap allocated Arm_exidx_section_offset_map is store in the located
1218 // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
1220 template<bool big_endian
>
1222 process_exidx_section(const Arm_exidx_input_section
* exidx_input_section
,
1223 Arm_exidx_section_offset_map
** psection_offset_map
);
1225 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1226 // input section, if there is not one already.
1228 add_exidx_cantunwind_as_needed();
1230 // Return the output section for the text section which is linked to the
1231 // first exidx input in output.
1233 first_output_text_section() const
1234 { return this->first_output_text_section_
; }
1237 // Copying is not allowed.
1238 Arm_exidx_fixup(const Arm_exidx_fixup
&);
1239 Arm_exidx_fixup
& operator=(const Arm_exidx_fixup
&);
1241 // Type of EXIDX unwind entry.
1246 // EXIDX_CANTUNWIND.
1247 UT_EXIDX_CANTUNWIND
,
1254 // Process an EXIDX entry. We only care about the second word of the
1255 // entry. Return true if the entry can be deleted.
1257 process_exidx_entry(uint32_t second_word
);
1259 // Update the current section offset map during EXIDX section fix-up.
1260 // If there is no map, create one. INPUT_OFFSET is the offset of a
1261 // reference point, DELETED_BYTES is the number of deleted by in the
1262 // section so far. If DELETE_ENTRY is true, the reference point and
1263 // all offsets after the previous reference point are discarded.
1265 update_offset_map(section_offset_type input_offset
,
1266 section_size_type deleted_bytes
, bool delete_entry
);
1268 // EXIDX output section.
1269 Output_section
* exidx_output_section_
;
1270 // Unwind type of the last EXIDX entry processed.
1271 Unwind_type last_unwind_type_
;
1272 // Last seen inlined EXIDX entry.
1273 uint32_t last_inlined_entry_
;
1274 // Last processed EXIDX input section.
1275 const Arm_exidx_input_section
* last_input_section_
;
1276 // Section offset map created in process_exidx_section.
1277 Arm_exidx_section_offset_map
* section_offset_map_
;
1278 // Output section for the text section which is linked to the first exidx
1280 Output_section
* first_output_text_section_
;
1283 // Arm output section class. This is defined mainly to add a number of
1284 // stub generation methods.
1286 template<bool big_endian
>
1287 class Arm_output_section
: public Output_section
1290 typedef std::vector
<std::pair
<Relobj
*, unsigned int> > Text_section_list
;
1292 Arm_output_section(const char* name
, elfcpp::Elf_Word type
,
1293 elfcpp::Elf_Xword flags
)
1294 : Output_section(name
, type
, flags
)
1297 ~Arm_output_section()
1300 // Group input sections for stub generation.
1302 group_sections(section_size_type
, bool, Target_arm
<big_endian
>*);
1304 // Downcast a base pointer to an Arm_output_section pointer. This is
1305 // not type-safe but we only use Arm_output_section not the base class.
1306 static Arm_output_section
<big_endian
>*
1307 as_arm_output_section(Output_section
* os
)
1308 { return static_cast<Arm_output_section
<big_endian
>*>(os
); }
1310 // Append all input text sections in this into LIST.
1312 append_text_sections_to_list(Text_section_list
* list
);
1314 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1315 // is a list of text input sections sorted in ascending order of their
1316 // output addresses.
1318 fix_exidx_coverage(const Text_section_list
& sorted_text_section
,
1319 Symbol_table
* symtab
);
1323 typedef Output_section::Input_section Input_section
;
1324 typedef Output_section::Input_section_list Input_section_list
;
1326 // Create a stub group.
1327 void create_stub_group(Input_section_list::const_iterator
,
1328 Input_section_list::const_iterator
,
1329 Input_section_list::const_iterator
,
1330 Target_arm
<big_endian
>*,
1331 std::vector
<Output_relaxed_input_section
*>*);
1334 // Arm_exidx_input_section class. This represents an EXIDX input section.
1336 class Arm_exidx_input_section
1339 static const section_offset_type invalid_offset
=
1340 static_cast<section_offset_type
>(-1);
1342 Arm_exidx_input_section(Relobj
* relobj
, unsigned int shndx
,
1343 unsigned int link
, uint32_t size
, uint32_t addralign
)
1344 : relobj_(relobj
), shndx_(shndx
), link_(link
), size_(size
),
1345 addralign_(addralign
)
1348 ~Arm_exidx_input_section()
1351 // Accessors: This is a read-only class.
1353 // Return the object containing this EXIDX input section.
1356 { return this->relobj_
; }
1358 // Return the section index of this EXIDX input section.
1361 { return this->shndx_
; }
1363 // Return the section index of linked text section in the same object.
1366 { return this->link_
; }
1368 // Return size of the EXIDX input section.
1371 { return this->size_
; }
1373 // Reutnr address alignment of EXIDX input section.
1376 { return this->addralign_
; }
1379 // Object containing this.
1381 // Section index of this.
1382 unsigned int shndx_
;
1383 // text section linked to this in the same object.
1385 // Size of this. For ARM 32-bit is sufficient.
1387 // Address alignment of this. For ARM 32-bit is sufficient.
1388 uint32_t addralign_
;
1391 // Arm_relobj class.
1393 template<bool big_endian
>
1394 class Arm_relobj
: public Sized_relobj
<32, big_endian
>
1397 static const Arm_address invalid_address
= static_cast<Arm_address
>(-1);
1399 Arm_relobj(const std::string
& name
, Input_file
* input_file
, off_t offset
,
1400 const typename
elfcpp::Ehdr
<32, big_endian
>& ehdr
)
1401 : Sized_relobj
<32, big_endian
>(name
, input_file
, offset
, ehdr
),
1402 stub_tables_(), local_symbol_is_thumb_function_(),
1403 attributes_section_data_(NULL
), mapping_symbols_info_(),
1404 section_has_cortex_a8_workaround_(NULL
), exidx_section_map_(),
1405 output_local_symbol_count_needs_update_(false)
1409 { delete this->attributes_section_data_
; }
1411 // Return the stub table of the SHNDX-th section if there is one.
1412 Stub_table
<big_endian
>*
1413 stub_table(unsigned int shndx
) const
1415 gold_assert(shndx
< this->stub_tables_
.size());
1416 return this->stub_tables_
[shndx
];
1419 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1421 set_stub_table(unsigned int shndx
, Stub_table
<big_endian
>* stub_table
)
1423 gold_assert(shndx
< this->stub_tables_
.size());
1424 this->stub_tables_
[shndx
] = stub_table
;
1427 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1428 // index. This is only valid after do_count_local_symbol is called.
1430 local_symbol_is_thumb_function(unsigned int r_sym
) const
1432 gold_assert(r_sym
< this->local_symbol_is_thumb_function_
.size());
1433 return this->local_symbol_is_thumb_function_
[r_sym
];
1436 // Scan all relocation sections for stub generation.
1438 scan_sections_for_stubs(Target_arm
<big_endian
>*, const Symbol_table
*,
1441 // Convert regular input section with index SHNDX to a relaxed section.
1443 convert_input_section_to_relaxed_section(unsigned shndx
)
1445 // The stubs have relocations and we need to process them after writing
1446 // out the stubs. So relocation now must follow section write.
1447 this->set_section_offset(shndx
, -1ULL);
1448 this->set_relocs_must_follow_section_writes();
1451 // Downcast a base pointer to an Arm_relobj pointer. This is
1452 // not type-safe but we only use Arm_relobj not the base class.
1453 static Arm_relobj
<big_endian
>*
1454 as_arm_relobj(Relobj
* relobj
)
1455 { return static_cast<Arm_relobj
<big_endian
>*>(relobj
); }
1457 // Processor-specific flags in ELF file header. This is valid only after
1460 processor_specific_flags() const
1461 { return this->processor_specific_flags_
; }
1463 // Attribute section data This is the contents of the .ARM.attribute section
1465 const Attributes_section_data
*
1466 attributes_section_data() const
1467 { return this->attributes_section_data_
; }
1469 // Mapping symbol location.
1470 typedef std::pair
<unsigned int, Arm_address
> Mapping_symbol_position
;
1472 // Functor for STL container.
1473 struct Mapping_symbol_position_less
1476 operator()(const Mapping_symbol_position
& p1
,
1477 const Mapping_symbol_position
& p2
) const
1479 return (p1
.first
< p2
.first
1480 || (p1
.first
== p2
.first
&& p1
.second
< p2
.second
));
1484 // We only care about the first character of a mapping symbol, so
1485 // we only store that instead of the whole symbol name.
1486 typedef std::map
<Mapping_symbol_position
, char,
1487 Mapping_symbol_position_less
> Mapping_symbols_info
;
1489 // Whether a section contains any Cortex-A8 workaround.
1491 section_has_cortex_a8_workaround(unsigned int shndx
) const
1493 return (this->section_has_cortex_a8_workaround_
!= NULL
1494 && (*this->section_has_cortex_a8_workaround_
)[shndx
]);
1497 // Mark a section that has Cortex-A8 workaround.
1499 mark_section_for_cortex_a8_workaround(unsigned int shndx
)
1501 if (this->section_has_cortex_a8_workaround_
== NULL
)
1502 this->section_has_cortex_a8_workaround_
=
1503 new std::vector
<bool>(this->shnum(), false);
1504 (*this->section_has_cortex_a8_workaround_
)[shndx
] = true;
1507 // Return the EXIDX section of an text section with index SHNDX or NULL
1508 // if the text section has no associated EXIDX section.
1509 const Arm_exidx_input_section
*
1510 exidx_input_section_by_link(unsigned int shndx
) const
1512 Exidx_section_map::const_iterator p
= this->exidx_section_map_
.find(shndx
);
1513 return ((p
!= this->exidx_section_map_
.end()
1514 && p
->second
->link() == shndx
)
1519 // Return the EXIDX section with index SHNDX or NULL if there is none.
1520 const Arm_exidx_input_section
*
1521 exidx_input_section_by_shndx(unsigned shndx
) const
1523 Exidx_section_map::const_iterator p
= this->exidx_section_map_
.find(shndx
);
1524 return ((p
!= this->exidx_section_map_
.end()
1525 && p
->second
->shndx() == shndx
)
1530 // Whether output local symbol count needs updating.
1532 output_local_symbol_count_needs_update() const
1533 { return this->output_local_symbol_count_needs_update_
; }
1535 // Set output_local_symbol_count_needs_update flag to be true.
1537 set_output_local_symbol_count_needs_update()
1538 { this->output_local_symbol_count_needs_update_
= true; }
1540 // Update output local symbol count at the end of relaxation.
1542 update_output_local_symbol_count();
1545 // Post constructor setup.
1549 // Call parent's setup method.
1550 Sized_relobj
<32, big_endian
>::do_setup();
1552 // Initialize look-up tables.
1553 Stub_table_list
empty_stub_table_list(this->shnum(), NULL
);
1554 this->stub_tables_
.swap(empty_stub_table_list
);
1557 // Count the local symbols.
1559 do_count_local_symbols(Stringpool_template
<char>*,
1560 Stringpool_template
<char>*);
1563 do_relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
1564 const unsigned char* pshdrs
,
1565 typename Sized_relobj
<32, big_endian
>::Views
* pivews
);
1567 // Read the symbol information.
1569 do_read_symbols(Read_symbols_data
* sd
);
1571 // Process relocs for garbage collection.
1573 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
1577 // Whether a section needs to be scanned for relocation stubs.
1579 section_needs_reloc_stub_scanning(const elfcpp::Shdr
<32, big_endian
>&,
1580 const Relobj::Output_sections
&,
1581 const Symbol_table
*, const unsigned char*);
1583 // Whether a section is a scannable text section.
1585 section_is_scannable(const elfcpp::Shdr
<32, big_endian
>&, unsigned int,
1586 const Output_section
*, const Symbol_table
*);
1588 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1590 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr
<32, big_endian
>&,
1591 unsigned int, Output_section
*,
1592 const Symbol_table
*);
1594 // Scan a section for the Cortex-A8 erratum.
1596 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr
<32, big_endian
>&,
1597 unsigned int, Output_section
*,
1598 Target_arm
<big_endian
>*);
1600 // Find the linked text section of an EXIDX section by looking at the
1601 // first reloction of the EXIDX section. PSHDR points to the section
1602 // headers of a relocation section and PSYMS points to the local symbols.
1603 // PSHNDX points to a location storing the text section index if found.
1604 // Return whether we can find the linked section.
1606 find_linked_text_section(const unsigned char* pshdr
,
1607 const unsigned char* psyms
, unsigned int* pshndx
);
1610 // Make a new Arm_exidx_input_section object for EXIDX section with
1611 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1612 // index of the linked text section.
1614 make_exidx_input_section(unsigned int shndx
,
1615 const elfcpp::Shdr
<32, big_endian
>& shdr
,
1616 unsigned int text_shndx
);
1618 // Return the output address of either a plain input section or a
1619 // relaxed input section. SHNDX is the section index.
1621 simple_input_section_output_address(unsigned int, Output_section
*);
1623 typedef std::vector
<Stub_table
<big_endian
>*> Stub_table_list
;
1624 typedef Unordered_map
<unsigned int, const Arm_exidx_input_section
*>
1627 // List of stub tables.
1628 Stub_table_list stub_tables_
;
1629 // Bit vector to tell if a local symbol is a thumb function or not.
1630 // This is only valid after do_count_local_symbol is called.
1631 std::vector
<bool> local_symbol_is_thumb_function_
;
1632 // processor-specific flags in ELF file header.
1633 elfcpp::Elf_Word processor_specific_flags_
;
1634 // Object attributes if there is an .ARM.attributes section or NULL.
1635 Attributes_section_data
* attributes_section_data_
;
1636 // Mapping symbols information.
1637 Mapping_symbols_info mapping_symbols_info_
;
1638 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1639 std::vector
<bool>* section_has_cortex_a8_workaround_
;
1640 // Map a text section to its associated .ARM.exidx section, if there is one.
1641 Exidx_section_map exidx_section_map_
;
1642 // Whether output local symbol count needs updating.
1643 bool output_local_symbol_count_needs_update_
;
1646 // Arm_dynobj class.
1648 template<bool big_endian
>
1649 class Arm_dynobj
: public Sized_dynobj
<32, big_endian
>
1652 Arm_dynobj(const std::string
& name
, Input_file
* input_file
, off_t offset
,
1653 const elfcpp::Ehdr
<32, big_endian
>& ehdr
)
1654 : Sized_dynobj
<32, big_endian
>(name
, input_file
, offset
, ehdr
),
1655 processor_specific_flags_(0), attributes_section_data_(NULL
)
1659 { delete this->attributes_section_data_
; }
1661 // Downcast a base pointer to an Arm_relobj pointer. This is
1662 // not type-safe but we only use Arm_relobj not the base class.
1663 static Arm_dynobj
<big_endian
>*
1664 as_arm_dynobj(Dynobj
* dynobj
)
1665 { return static_cast<Arm_dynobj
<big_endian
>*>(dynobj
); }
1667 // Processor-specific flags in ELF file header. This is valid only after
1670 processor_specific_flags() const
1671 { return this->processor_specific_flags_
; }
1673 // Attributes section data.
1674 const Attributes_section_data
*
1675 attributes_section_data() const
1676 { return this->attributes_section_data_
; }
1679 // Read the symbol information.
1681 do_read_symbols(Read_symbols_data
* sd
);
1684 // processor-specific flags in ELF file header.
1685 elfcpp::Elf_Word processor_specific_flags_
;
1686 // Object attributes if there is an .ARM.attributes section or NULL.
1687 Attributes_section_data
* attributes_section_data_
;
1690 // Functor to read reloc addends during stub generation.
1692 template<int sh_type
, bool big_endian
>
1693 struct Stub_addend_reader
1695 // Return the addend for a relocation of a particular type. Depending
1696 // on whether this is a REL or RELA relocation, read the addend from a
1697 // view or from a Reloc object.
1698 elfcpp::Elf_types
<32>::Elf_Swxword
1700 unsigned int /* r_type */,
1701 const unsigned char* /* view */,
1702 const typename Reloc_types
<sh_type
,
1703 32, big_endian
>::Reloc
& /* reloc */) const;
1706 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1708 template<bool big_endian
>
1709 struct Stub_addend_reader
<elfcpp::SHT_REL
, big_endian
>
1711 elfcpp::Elf_types
<32>::Elf_Swxword
1714 const unsigned char*,
1715 const typename Reloc_types
<elfcpp::SHT_REL
, 32, big_endian
>::Reloc
&) const;
1718 // Specialized Stub_addend_reader for RELA type relocation sections.
1719 // We currently do not handle RELA type relocation sections but it is trivial
1720 // to implement the addend reader. This is provided for completeness and to
1721 // make it easier to add support for RELA relocation sections in the future.
1723 template<bool big_endian
>
1724 struct Stub_addend_reader
<elfcpp::SHT_RELA
, big_endian
>
1726 elfcpp::Elf_types
<32>::Elf_Swxword
1729 const unsigned char*,
1730 const typename Reloc_types
<elfcpp::SHT_RELA
, 32,
1731 big_endian
>::Reloc
& reloc
) const
1732 { return reloc
.get_r_addend(); }
1735 // Cortex_a8_reloc class. We keep record of relocation that may need
1736 // the Cortex-A8 erratum workaround.
1738 class Cortex_a8_reloc
1741 Cortex_a8_reloc(Reloc_stub
* reloc_stub
, unsigned r_type
,
1742 Arm_address destination
)
1743 : reloc_stub_(reloc_stub
), r_type_(r_type
), destination_(destination
)
1749 // Accessors: This is a read-only class.
1751 // Return the relocation stub associated with this relocation if there is
1755 { return this->reloc_stub_
; }
1757 // Return the relocation type.
1760 { return this->r_type_
; }
1762 // Return the destination address of the relocation. LSB stores the THUMB
1766 { return this->destination_
; }
1769 // Associated relocation stub if there is one, or NULL.
1770 const Reloc_stub
* reloc_stub_
;
1772 unsigned int r_type_
;
1773 // Destination address of this relocation. LSB is used to distinguish
1775 Arm_address destination_
;
1778 // Utilities for manipulating integers of up to 32-bits
1782 // Sign extend an n-bit unsigned integer stored in an uint32_t into
1783 // an int32_t. NO_BITS must be between 1 to 32.
1784 template<int no_bits
>
1785 static inline int32_t
1786 sign_extend(uint32_t bits
)
1788 gold_assert(no_bits
>= 0 && no_bits
<= 32);
1790 return static_cast<int32_t>(bits
);
1791 uint32_t mask
= (~((uint32_t) 0)) >> (32 - no_bits
);
1793 uint32_t top_bit
= 1U << (no_bits
- 1);
1794 int32_t as_signed
= static_cast<int32_t>(bits
);
1795 return (bits
& top_bit
) ? as_signed
+ (-top_bit
* 2) : as_signed
;
1798 // Detects overflow of an NO_BITS integer stored in a uint32_t.
1799 template<int no_bits
>
1801 has_overflow(uint32_t bits
)
1803 gold_assert(no_bits
>= 0 && no_bits
<= 32);
1806 int32_t max
= (1 << (no_bits
- 1)) - 1;
1807 int32_t min
= -(1 << (no_bits
- 1));
1808 int32_t as_signed
= static_cast<int32_t>(bits
);
1809 return as_signed
> max
|| as_signed
< min
;
1812 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
1813 // fits in the given number of bits as either a signed or unsigned value.
1814 // For example, has_signed_unsigned_overflow<8> would check
1815 // -128 <= bits <= 255
1816 template<int no_bits
>
1818 has_signed_unsigned_overflow(uint32_t bits
)
1820 gold_assert(no_bits
>= 2 && no_bits
<= 32);
1823 int32_t max
= static_cast<int32_t>((1U << no_bits
) - 1);
1824 int32_t min
= -(1 << (no_bits
- 1));
1825 int32_t as_signed
= static_cast<int32_t>(bits
);
1826 return as_signed
> max
|| as_signed
< min
;
1829 // Select bits from A and B using bits in MASK. For each n in [0..31],
1830 // the n-th bit in the result is chosen from the n-th bits of A and B.
1831 // A zero selects A and a one selects B.
1832 static inline uint32_t
1833 bit_select(uint32_t a
, uint32_t b
, uint32_t mask
)
1834 { return (a
& ~mask
) | (b
& mask
); }
1837 template<bool big_endian
>
1838 class Target_arm
: public Sized_target
<32, big_endian
>
1841 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, big_endian
>
1844 // When were are relocating a stub, we pass this as the relocation number.
1845 static const size_t fake_relnum_for_stubs
= static_cast<size_t>(-1);
1848 : Sized_target
<32, big_endian
>(&arm_info
),
1849 got_(NULL
), plt_(NULL
), got_plt_(NULL
), rel_dyn_(NULL
),
1850 copy_relocs_(elfcpp::R_ARM_COPY
), dynbss_(NULL
), stub_tables_(),
1851 stub_factory_(Stub_factory::get_instance()), may_use_blx_(false),
1852 should_force_pic_veneer_(false), arm_input_section_map_(),
1853 attributes_section_data_(NULL
), fix_cortex_a8_(false),
1854 cortex_a8_relocs_info_()
1857 // Whether we can use BLX.
1860 { return this->may_use_blx_
; }
1862 // Set use-BLX flag.
1864 set_may_use_blx(bool value
)
1865 { this->may_use_blx_
= value
; }
1867 // Whether we force PCI branch veneers.
1869 should_force_pic_veneer() const
1870 { return this->should_force_pic_veneer_
; }
1872 // Set PIC veneer flag.
1874 set_should_force_pic_veneer(bool value
)
1875 { this->should_force_pic_veneer_
= value
; }
1877 // Whether we use THUMB-2 instructions.
1879 using_thumb2() const
1881 Object_attribute
* attr
=
1882 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1883 int arch
= attr
->int_value();
1884 return arch
== elfcpp::TAG_CPU_ARCH_V6T2
|| arch
>= elfcpp::TAG_CPU_ARCH_V7
;
1887 // Whether we use THUMB/THUMB-2 instructions only.
1889 using_thumb_only() const
1891 Object_attribute
* attr
=
1892 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1893 if (attr
->int_value() != elfcpp::TAG_CPU_ARCH_V7
1894 && attr
->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M
)
1896 attr
= this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile
);
1897 return attr
->int_value() == 'M';
1900 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
1902 may_use_arm_nop() const
1904 Object_attribute
* attr
=
1905 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1906 int arch
= attr
->int_value();
1907 return (arch
== elfcpp::TAG_CPU_ARCH_V6T2
1908 || arch
== elfcpp::TAG_CPU_ARCH_V6K
1909 || arch
== elfcpp::TAG_CPU_ARCH_V7
1910 || arch
== elfcpp::TAG_CPU_ARCH_V7E_M
);
1913 // Whether we have THUMB-2 NOP.W instruction.
1915 may_use_thumb2_nop() const
1917 Object_attribute
* attr
=
1918 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1919 int arch
= attr
->int_value();
1920 return (arch
== elfcpp::TAG_CPU_ARCH_V6T2
1921 || arch
== elfcpp::TAG_CPU_ARCH_V7
1922 || arch
== elfcpp::TAG_CPU_ARCH_V7E_M
);
1925 // Process the relocations to determine unreferenced sections for
1926 // garbage collection.
1928 gc_process_relocs(Symbol_table
* symtab
,
1930 Sized_relobj
<32, big_endian
>* object
,
1931 unsigned int data_shndx
,
1932 unsigned int sh_type
,
1933 const unsigned char* prelocs
,
1935 Output_section
* output_section
,
1936 bool needs_special_offset_handling
,
1937 size_t local_symbol_count
,
1938 const unsigned char* plocal_symbols
);
1940 // Scan the relocations to look for symbol adjustments.
1942 scan_relocs(Symbol_table
* symtab
,
1944 Sized_relobj
<32, big_endian
>* object
,
1945 unsigned int data_shndx
,
1946 unsigned int sh_type
,
1947 const unsigned char* prelocs
,
1949 Output_section
* output_section
,
1950 bool needs_special_offset_handling
,
1951 size_t local_symbol_count
,
1952 const unsigned char* plocal_symbols
);
1954 // Finalize the sections.
1956 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
1958 // Return the value to use for a dynamic symbol which requires special
1961 do_dynsym_value(const Symbol
*) const;
1963 // Relocate a section.
1965 relocate_section(const Relocate_info
<32, big_endian
>*,
1966 unsigned int sh_type
,
1967 const unsigned char* prelocs
,
1969 Output_section
* output_section
,
1970 bool needs_special_offset_handling
,
1971 unsigned char* view
,
1972 Arm_address view_address
,
1973 section_size_type view_size
,
1974 const Reloc_symbol_changes
*);
1976 // Scan the relocs during a relocatable link.
1978 scan_relocatable_relocs(Symbol_table
* symtab
,
1980 Sized_relobj
<32, big_endian
>* object
,
1981 unsigned int data_shndx
,
1982 unsigned int sh_type
,
1983 const unsigned char* prelocs
,
1985 Output_section
* output_section
,
1986 bool needs_special_offset_handling
,
1987 size_t local_symbol_count
,
1988 const unsigned char* plocal_symbols
,
1989 Relocatable_relocs
*);
1991 // Relocate a section during a relocatable link.
1993 relocate_for_relocatable(const Relocate_info
<32, big_endian
>*,
1994 unsigned int sh_type
,
1995 const unsigned char* prelocs
,
1997 Output_section
* output_section
,
1998 off_t offset_in_output_section
,
1999 const Relocatable_relocs
*,
2000 unsigned char* view
,
2001 Arm_address view_address
,
2002 section_size_type view_size
,
2003 unsigned char* reloc_view
,
2004 section_size_type reloc_view_size
);
2006 // Return whether SYM is defined by the ABI.
2008 do_is_defined_by_abi(Symbol
* sym
) const
2009 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
2011 // Return whether there is a GOT section.
2013 has_got_section() const
2014 { return this->got_
!= NULL
; }
2016 // Return the size of the GOT section.
2020 gold_assert(this->got_
!= NULL
);
2021 return this->got_
->data_size();
2024 // Map platform-specific reloc types
2026 get_real_reloc_type (unsigned int r_type
);
2029 // Methods to support stub-generations.
2032 // Return the stub factory
2034 stub_factory() const
2035 { return this->stub_factory_
; }
2037 // Make a new Arm_input_section object.
2038 Arm_input_section
<big_endian
>*
2039 new_arm_input_section(Relobj
*, unsigned int);
2041 // Find the Arm_input_section object corresponding to the SHNDX-th input
2042 // section of RELOBJ.
2043 Arm_input_section
<big_endian
>*
2044 find_arm_input_section(Relobj
* relobj
, unsigned int shndx
) const;
2046 // Make a new Stub_table
2047 Stub_table
<big_endian
>*
2048 new_stub_table(Arm_input_section
<big_endian
>*);
2050 // Scan a section for stub generation.
2052 scan_section_for_stubs(const Relocate_info
<32, big_endian
>*, unsigned int,
2053 const unsigned char*, size_t, Output_section
*,
2054 bool, const unsigned char*, Arm_address
,
2059 relocate_stub(Stub
*, const Relocate_info
<32, big_endian
>*,
2060 Output_section
*, unsigned char*, Arm_address
,
2063 // Get the default ARM target.
2064 static Target_arm
<big_endian
>*
2067 gold_assert(parameters
->target().machine_code() == elfcpp::EM_ARM
2068 && parameters
->target().is_big_endian() == big_endian
);
2069 return static_cast<Target_arm
<big_endian
>*>(
2070 parameters
->sized_target
<32, big_endian
>());
2073 // Whether NAME belongs to a mapping symbol.
2075 is_mapping_symbol_name(const char* name
)
2079 && (name
[1] == 'a' || name
[1] == 't' || name
[1] == 'd')
2080 && (name
[2] == '\0' || name
[2] == '.'));
2083 // Whether we work around the Cortex-A8 erratum.
2085 fix_cortex_a8() const
2086 { return this->fix_cortex_a8_
; }
2088 // Whether we fix R_ARM_V4BX relocation.
2090 // 1 - replace with MOV instruction (armv4 target)
2091 // 2 - make interworking veneer (>= armv4t targets only)
2092 General_options::Fix_v4bx
2094 { return parameters
->options().fix_v4bx(); }
2096 // Scan a span of THUMB code section for Cortex-A8 erratum.
2098 scan_span_for_cortex_a8_erratum(Arm_relobj
<big_endian
>*, unsigned int,
2099 section_size_type
, section_size_type
,
2100 const unsigned char*, Arm_address
);
2102 // Apply Cortex-A8 workaround to a branch.
2104 apply_cortex_a8_workaround(const Cortex_a8_stub
*, Arm_address
,
2105 unsigned char*, Arm_address
);
2108 // Make an ELF object.
2110 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
2111 const elfcpp::Ehdr
<32, big_endian
>& ehdr
);
2114 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
2115 const elfcpp::Ehdr
<32, !big_endian
>&)
2116 { gold_unreachable(); }
2119 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
2120 const elfcpp::Ehdr
<64, false>&)
2121 { gold_unreachable(); }
2124 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
2125 const elfcpp::Ehdr
<64, true>&)
2126 { gold_unreachable(); }
2128 // Make an output section.
2130 do_make_output_section(const char* name
, elfcpp::Elf_Word type
,
2131 elfcpp::Elf_Xword flags
)
2132 { return new Arm_output_section
<big_endian
>(name
, type
, flags
); }
2135 do_adjust_elf_header(unsigned char* view
, int len
) const;
2137 // We only need to generate stubs, and hence perform relaxation if we are
2138 // not doing relocatable linking.
2140 do_may_relax() const
2141 { return !parameters
->options().relocatable(); }
2144 do_relax(int, const Input_objects
*, Symbol_table
*, Layout
*);
2146 // Determine whether an object attribute tag takes an integer, a
2149 do_attribute_arg_type(int tag
) const;
2151 // Reorder tags during output.
2153 do_attributes_order(int num
) const;
2155 // This is called when the target is selected as the default.
2157 do_select_as_default_target()
2159 // No locking is required since there should only be one default target.
2160 // We cannot have both the big-endian and little-endian ARM targets
2162 gold_assert(arm_reloc_property_table
== NULL
);
2163 arm_reloc_property_table
= new Arm_reloc_property_table();
2167 // The class which scans relocations.
2172 : issued_non_pic_error_(false)
2176 local(Symbol_table
* symtab
, Layout
* layout
, Target_arm
* target
,
2177 Sized_relobj
<32, big_endian
>* object
,
2178 unsigned int data_shndx
,
2179 Output_section
* output_section
,
2180 const elfcpp::Rel
<32, big_endian
>& reloc
, unsigned int r_type
,
2181 const elfcpp::Sym
<32, big_endian
>& lsym
);
2184 global(Symbol_table
* symtab
, Layout
* layout
, Target_arm
* target
,
2185 Sized_relobj
<32, big_endian
>* object
,
2186 unsigned int data_shndx
,
2187 Output_section
* output_section
,
2188 const elfcpp::Rel
<32, big_endian
>& reloc
, unsigned int r_type
,
2192 local_reloc_may_be_function_pointer(Symbol_table
* , Layout
* , Target_arm
* ,
2193 Sized_relobj
<32, big_endian
>* ,
2196 const elfcpp::Rel
<32, big_endian
>& ,
2198 const elfcpp::Sym
<32, big_endian
>&)
2202 global_reloc_may_be_function_pointer(Symbol_table
* , Layout
* , Target_arm
* ,
2203 Sized_relobj
<32, big_endian
>* ,
2206 const elfcpp::Rel
<32, big_endian
>& ,
2207 unsigned int , Symbol
*)
2212 unsupported_reloc_local(Sized_relobj
<32, big_endian
>*,
2213 unsigned int r_type
);
2216 unsupported_reloc_global(Sized_relobj
<32, big_endian
>*,
2217 unsigned int r_type
, Symbol
*);
2220 check_non_pic(Relobj
*, unsigned int r_type
);
2222 // Almost identical to Symbol::needs_plt_entry except that it also
2223 // handles STT_ARM_TFUNC.
2225 symbol_needs_plt_entry(const Symbol
* sym
)
2227 // An undefined symbol from an executable does not need a PLT entry.
2228 if (sym
->is_undefined() && !parameters
->options().shared())
2231 return (!parameters
->doing_static_link()
2232 && (sym
->type() == elfcpp::STT_FUNC
2233 || sym
->type() == elfcpp::STT_ARM_TFUNC
)
2234 && (sym
->is_from_dynobj()
2235 || sym
->is_undefined()
2236 || sym
->is_preemptible()));
2239 // Whether we have issued an error about a non-PIC compilation.
2240 bool issued_non_pic_error_
;
2243 // The class which implements relocation.
2253 // Return whether the static relocation needs to be applied.
2255 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2258 Output_section
* output_section
);
2260 // Do a relocation. Return false if the caller should not issue
2261 // any warnings about this relocation.
2263 relocate(const Relocate_info
<32, big_endian
>*, Target_arm
*,
2264 Output_section
*, size_t relnum
,
2265 const elfcpp::Rel
<32, big_endian
>&,
2266 unsigned int r_type
, const Sized_symbol
<32>*,
2267 const Symbol_value
<32>*,
2268 unsigned char*, Arm_address
,
2271 // Return whether we want to pass flag NON_PIC_REF for this
2272 // reloc. This means the relocation type accesses a symbol not via
2275 reloc_is_non_pic (unsigned int r_type
)
2279 // These relocation types reference GOT or PLT entries explicitly.
2280 case elfcpp::R_ARM_GOT_BREL
:
2281 case elfcpp::R_ARM_GOT_ABS
:
2282 case elfcpp::R_ARM_GOT_PREL
:
2283 case elfcpp::R_ARM_GOT_BREL12
:
2284 case elfcpp::R_ARM_PLT32_ABS
:
2285 case elfcpp::R_ARM_TLS_GD32
:
2286 case elfcpp::R_ARM_TLS_LDM32
:
2287 case elfcpp::R_ARM_TLS_IE32
:
2288 case elfcpp::R_ARM_TLS_IE12GP
:
2290 // These relocate types may use PLT entries.
2291 case elfcpp::R_ARM_CALL
:
2292 case elfcpp::R_ARM_THM_CALL
:
2293 case elfcpp::R_ARM_JUMP24
:
2294 case elfcpp::R_ARM_THM_JUMP24
:
2295 case elfcpp::R_ARM_THM_JUMP19
:
2296 case elfcpp::R_ARM_PLT32
:
2297 case elfcpp::R_ARM_THM_XPC22
:
2306 // A class which returns the size required for a relocation type,
2307 // used while scanning relocs during a relocatable link.
2308 class Relocatable_size_for_reloc
2312 get_size_for_reloc(unsigned int, Relobj
*);
2315 // Get the GOT section, creating it if necessary.
2316 Output_data_got
<32, big_endian
>*
2317 got_section(Symbol_table
*, Layout
*);
2319 // Get the GOT PLT section.
2321 got_plt_section() const
2323 gold_assert(this->got_plt_
!= NULL
);
2324 return this->got_plt_
;
2327 // Create a PLT entry for a global symbol.
2329 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
2331 // Get the PLT section.
2332 const Output_data_plt_arm
<big_endian
>*
2335 gold_assert(this->plt_
!= NULL
);
2339 // Get the dynamic reloc section, creating it if necessary.
2341 rel_dyn_section(Layout
*);
2343 // Return true if the symbol may need a COPY relocation.
2344 // References from an executable object to non-function symbols
2345 // defined in a dynamic object may need a COPY relocation.
2347 may_need_copy_reloc(Symbol
* gsym
)
2349 return (gsym
->type() != elfcpp::STT_ARM_TFUNC
2350 && gsym
->may_need_copy_reloc());
2353 // Add a potential copy relocation.
2355 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
2356 Sized_relobj
<32, big_endian
>* object
,
2357 unsigned int shndx
, Output_section
* output_section
,
2358 Symbol
* sym
, const elfcpp::Rel
<32, big_endian
>& reloc
)
2360 this->copy_relocs_
.copy_reloc(symtab
, layout
,
2361 symtab
->get_sized_symbol
<32>(sym
),
2362 object
, shndx
, output_section
, reloc
,
2363 this->rel_dyn_section(layout
));
2366 // Whether two EABI versions are compatible.
2368 are_eabi_versions_compatible(elfcpp::Elf_Word v1
, elfcpp::Elf_Word v2
);
2370 // Merge processor-specific flags from input object and those in the ELF
2371 // header of the output.
2373 merge_processor_specific_flags(const std::string
&, elfcpp::Elf_Word
);
2375 // Get the secondary compatible architecture.
2377 get_secondary_compatible_arch(const Attributes_section_data
*);
2379 // Set the secondary compatible architecture.
2381 set_secondary_compatible_arch(Attributes_section_data
*, int);
2384 tag_cpu_arch_combine(const char*, int, int*, int, int);
2386 // Helper to print AEABI enum tag value.
2388 aeabi_enum_name(unsigned int);
2390 // Return string value for TAG_CPU_name.
2392 tag_cpu_name_value(unsigned int);
2394 // Merge object attributes from input object and those in the output.
2396 merge_object_attributes(const char*, const Attributes_section_data
*);
2398 // Helper to get an AEABI object attribute
2400 get_aeabi_object_attribute(int tag
) const
2402 Attributes_section_data
* pasd
= this->attributes_section_data_
;
2403 gold_assert(pasd
!= NULL
);
2404 Object_attribute
* attr
=
2405 pasd
->get_attribute(Object_attribute::OBJ_ATTR_PROC
, tag
);
2406 gold_assert(attr
!= NULL
);
2411 // Methods to support stub-generations.
2414 // Group input sections for stub generation.
2416 group_sections(Layout
*, section_size_type
, bool);
2418 // Scan a relocation for stub generation.
2420 scan_reloc_for_stub(const Relocate_info
<32, big_endian
>*, unsigned int,
2421 const Sized_symbol
<32>*, unsigned int,
2422 const Symbol_value
<32>*,
2423 elfcpp::Elf_types
<32>::Elf_Swxword
, Arm_address
);
2425 // Scan a relocation section for stub.
2426 template<int sh_type
>
2428 scan_reloc_section_for_stubs(
2429 const Relocate_info
<32, big_endian
>* relinfo
,
2430 const unsigned char* prelocs
,
2432 Output_section
* output_section
,
2433 bool needs_special_offset_handling
,
2434 const unsigned char* view
,
2435 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2438 // Fix .ARM.exidx section coverage.
2440 fix_exidx_coverage(Layout
*, Arm_output_section
<big_endian
>*, Symbol_table
*);
2442 // Functors for STL set.
2443 struct output_section_address_less_than
2446 operator()(const Output_section
* s1
, const Output_section
* s2
) const
2447 { return s1
->address() < s2
->address(); }
2450 // Information about this specific target which we pass to the
2451 // general Target structure.
2452 static const Target::Target_info arm_info
;
2454 // The types of GOT entries needed for this platform.
2457 GOT_TYPE_STANDARD
= 0 // GOT entry for a regular symbol
2460 typedef typename
std::vector
<Stub_table
<big_endian
>*> Stub_table_list
;
2462 // Map input section to Arm_input_section.
2463 typedef Unordered_map
<Section_id
,
2464 Arm_input_section
<big_endian
>*,
2466 Arm_input_section_map
;
2468 // Map output addresses to relocs for Cortex-A8 erratum.
2469 typedef Unordered_map
<Arm_address
, const Cortex_a8_reloc
*>
2470 Cortex_a8_relocs_info
;
2473 Output_data_got
<32, big_endian
>* got_
;
2475 Output_data_plt_arm
<big_endian
>* plt_
;
2476 // The GOT PLT section.
2477 Output_data_space
* got_plt_
;
2478 // The dynamic reloc section.
2479 Reloc_section
* rel_dyn_
;
2480 // Relocs saved to avoid a COPY reloc.
2481 Copy_relocs
<elfcpp::SHT_REL
, 32, big_endian
> copy_relocs_
;
2482 // Space for variables copied with a COPY reloc.
2483 Output_data_space
* dynbss_
;
2484 // Vector of Stub_tables created.
2485 Stub_table_list stub_tables_
;
2487 const Stub_factory
&stub_factory_
;
2488 // Whether we can use BLX.
2490 // Whether we force PIC branch veneers.
2491 bool should_force_pic_veneer_
;
2492 // Map for locating Arm_input_sections.
2493 Arm_input_section_map arm_input_section_map_
;
2494 // Attributes section data in output.
2495 Attributes_section_data
* attributes_section_data_
;
2496 // Whether we want to fix code for Cortex-A8 erratum.
2497 bool fix_cortex_a8_
;
2498 // Map addresses to relocs for Cortex-A8 erratum.
2499 Cortex_a8_relocs_info cortex_a8_relocs_info_
;
2502 template<bool big_endian
>
2503 const Target::Target_info Target_arm
<big_endian
>::arm_info
=
2506 big_endian
, // is_big_endian
2507 elfcpp::EM_ARM
, // machine_code
2508 false, // has_make_symbol
2509 false, // has_resolve
2510 false, // has_code_fill
2511 true, // is_default_stack_executable
2513 "/usr/lib/libc.so.1", // dynamic_linker
2514 0x8000, // default_text_segment_address
2515 0x1000, // abi_pagesize (overridable by -z max-page-size)
2516 0x1000, // common_pagesize (overridable by -z common-page-size)
2517 elfcpp::SHN_UNDEF
, // small_common_shndx
2518 elfcpp::SHN_UNDEF
, // large_common_shndx
2519 0, // small_common_section_flags
2520 0, // large_common_section_flags
2521 ".ARM.attributes", // attributes_section
2522 "aeabi" // attributes_vendor
2525 // Arm relocate functions class
2528 template<bool big_endian
>
2529 class Arm_relocate_functions
: public Relocate_functions
<32, big_endian
>
2534 STATUS_OKAY
, // No error during relocation.
2535 STATUS_OVERFLOW
, // Relocation oveflow.
2536 STATUS_BAD_RELOC
// Relocation cannot be applied.
2540 typedef Relocate_functions
<32, big_endian
> Base
;
2541 typedef Arm_relocate_functions
<big_endian
> This
;
2543 // Encoding of imm16 argument for movt and movw ARM instructions
2546 // imm16 := imm4 | imm12
2548 // 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
2549 // +-------+---------------+-------+-------+-----------------------+
2550 // | | |imm4 | |imm12 |
2551 // +-------+---------------+-------+-------+-----------------------+
2553 // Extract the relocation addend from VAL based on the ARM
2554 // instruction encoding described above.
2555 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2556 extract_arm_movw_movt_addend(
2557 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
)
2559 // According to the Elf ABI for ARM Architecture the immediate
2560 // field is sign-extended to form the addend.
2561 return utils::sign_extend
<16>(((val
>> 4) & 0xf000) | (val
& 0xfff));
2564 // Insert X into VAL based on the ARM instruction encoding described
2566 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2567 insert_val_arm_movw_movt(
2568 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
,
2569 typename
elfcpp::Swap
<32, big_endian
>::Valtype x
)
2573 val
|= (x
& 0xf000) << 4;
2577 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2580 // imm16 := imm4 | i | imm3 | imm8
2582 // 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
2583 // +---------+-+-----------+-------++-+-----+-------+---------------+
2584 // | |i| |imm4 || |imm3 | |imm8 |
2585 // +---------+-+-----------+-------++-+-----+-------+---------------+
2587 // Extract the relocation addend from VAL based on the Thumb2
2588 // instruction encoding described above.
2589 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2590 extract_thumb_movw_movt_addend(
2591 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
)
2593 // According to the Elf ABI for ARM Architecture the immediate
2594 // field is sign-extended to form the addend.
2595 return utils::sign_extend
<16>(((val
>> 4) & 0xf000)
2596 | ((val
>> 15) & 0x0800)
2597 | ((val
>> 4) & 0x0700)
2601 // Insert X into VAL based on the Thumb2 instruction encoding
2603 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2604 insert_val_thumb_movw_movt(
2605 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
,
2606 typename
elfcpp::Swap
<32, big_endian
>::Valtype x
)
2609 val
|= (x
& 0xf000) << 4;
2610 val
|= (x
& 0x0800) << 15;
2611 val
|= (x
& 0x0700) << 4;
2612 val
|= (x
& 0x00ff);
2616 // Calculate the smallest constant Kn for the specified residual.
2617 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2619 calc_grp_kn(typename
elfcpp::Swap
<32, big_endian
>::Valtype residual
)
2625 // Determine the most significant bit in the residual and
2626 // align the resulting value to a 2-bit boundary.
2627 for (msb
= 30; (msb
>= 0) && !(residual
& (3 << msb
)); msb
-= 2)
2629 // The desired shift is now (msb - 6), or zero, whichever
2631 return (((msb
- 6) < 0) ? 0 : (msb
- 6));
2634 // Calculate the final residual for the specified group index.
2635 // If the passed group index is less than zero, the method will return
2636 // the value of the specified residual without any change.
2637 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2638 static typename
elfcpp::Swap
<32, big_endian
>::Valtype
2639 calc_grp_residual(typename
elfcpp::Swap
<32, big_endian
>::Valtype residual
,
2642 for (int n
= 0; n
<= group
; n
++)
2644 // Calculate which part of the value to mask.
2645 uint32_t shift
= calc_grp_kn(residual
);
2646 // Calculate the residual for the next time around.
2647 residual
&= ~(residual
& (0xff << shift
));
2653 // Calculate the value of Gn for the specified group index.
2654 // We return it in the form of an encoded constant-and-rotation.
2655 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2656 static typename
elfcpp::Swap
<32, big_endian
>::Valtype
2657 calc_grp_gn(typename
elfcpp::Swap
<32, big_endian
>::Valtype residual
,
2660 typename
elfcpp::Swap
<32, big_endian
>::Valtype gn
= 0;
2663 for (int n
= 0; n
<= group
; n
++)
2665 // Calculate which part of the value to mask.
2666 shift
= calc_grp_kn(residual
);
2667 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
2668 gn
= residual
& (0xff << shift
);
2669 // Calculate the residual for the next time around.
2672 // Return Gn in the form of an encoded constant-and-rotation.
2673 return ((gn
>> shift
) | ((gn
<= 0xff ? 0 : (32 - shift
) / 2) << 8));
2677 // Handle ARM long branches.
2678 static typename
This::Status
2679 arm_branch_common(unsigned int, const Relocate_info
<32, big_endian
>*,
2680 unsigned char *, const Sized_symbol
<32>*,
2681 const Arm_relobj
<big_endian
>*, unsigned int,
2682 const Symbol_value
<32>*, Arm_address
, Arm_address
, bool);
2684 // Handle THUMB long branches.
2685 static typename
This::Status
2686 thumb_branch_common(unsigned int, const Relocate_info
<32, big_endian
>*,
2687 unsigned char *, const Sized_symbol
<32>*,
2688 const Arm_relobj
<big_endian
>*, unsigned int,
2689 const Symbol_value
<32>*, Arm_address
, Arm_address
, bool);
2692 // Return the branch offset of a 32-bit THUMB branch.
2693 static inline int32_t
2694 thumb32_branch_offset(uint16_t upper_insn
, uint16_t lower_insn
)
2696 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
2697 // involving the J1 and J2 bits.
2698 uint32_t s
= (upper_insn
& (1U << 10)) >> 10;
2699 uint32_t upper
= upper_insn
& 0x3ffU
;
2700 uint32_t lower
= lower_insn
& 0x7ffU
;
2701 uint32_t j1
= (lower_insn
& (1U << 13)) >> 13;
2702 uint32_t j2
= (lower_insn
& (1U << 11)) >> 11;
2703 uint32_t i1
= j1
^ s
? 0 : 1;
2704 uint32_t i2
= j2
^ s
? 0 : 1;
2706 return utils::sign_extend
<25>((s
<< 24) | (i1
<< 23) | (i2
<< 22)
2707 | (upper
<< 12) | (lower
<< 1));
2710 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
2711 // UPPER_INSN is the original upper instruction of the branch. Caller is
2712 // responsible for overflow checking and BLX offset adjustment.
2713 static inline uint16_t
2714 thumb32_branch_upper(uint16_t upper_insn
, int32_t offset
)
2716 uint32_t s
= offset
< 0 ? 1 : 0;
2717 uint32_t bits
= static_cast<uint32_t>(offset
);
2718 return (upper_insn
& ~0x7ffU
) | ((bits
>> 12) & 0x3ffU
) | (s
<< 10);
2721 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
2722 // LOWER_INSN is the original lower instruction of the branch. Caller is
2723 // responsible for overflow checking and BLX offset adjustment.
2724 static inline uint16_t
2725 thumb32_branch_lower(uint16_t lower_insn
, int32_t offset
)
2727 uint32_t s
= offset
< 0 ? 1 : 0;
2728 uint32_t bits
= static_cast<uint32_t>(offset
);
2729 return ((lower_insn
& ~0x2fffU
)
2730 | ((((bits
>> 23) & 1) ^ !s
) << 13)
2731 | ((((bits
>> 22) & 1) ^ !s
) << 11)
2732 | ((bits
>> 1) & 0x7ffU
));
2735 // Return the branch offset of a 32-bit THUMB conditional branch.
2736 static inline int32_t
2737 thumb32_cond_branch_offset(uint16_t upper_insn
, uint16_t lower_insn
)
2739 uint32_t s
= (upper_insn
& 0x0400U
) >> 10;
2740 uint32_t j1
= (lower_insn
& 0x2000U
) >> 13;
2741 uint32_t j2
= (lower_insn
& 0x0800U
) >> 11;
2742 uint32_t lower
= (lower_insn
& 0x07ffU
);
2743 uint32_t upper
= (s
<< 8) | (j2
<< 7) | (j1
<< 6) | (upper_insn
& 0x003fU
);
2745 return utils::sign_extend
<21>((upper
<< 12) | (lower
<< 1));
2748 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
2749 // instruction. UPPER_INSN is the original upper instruction of the branch.
2750 // Caller is responsible for overflow checking.
2751 static inline uint16_t
2752 thumb32_cond_branch_upper(uint16_t upper_insn
, int32_t offset
)
2754 uint32_t s
= offset
< 0 ? 1 : 0;
2755 uint32_t bits
= static_cast<uint32_t>(offset
);
2756 return (upper_insn
& 0xfbc0U
) | (s
<< 10) | ((bits
& 0x0003f000U
) >> 12);
2759 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
2760 // instruction. LOWER_INSN is the original lower instruction of the branch.
2761 // Caller is reponsible for overflow checking.
2762 static inline uint16_t
2763 thumb32_cond_branch_lower(uint16_t lower_insn
, int32_t offset
)
2765 uint32_t bits
= static_cast<uint32_t>(offset
);
2766 uint32_t j2
= (bits
& 0x00080000U
) >> 19;
2767 uint32_t j1
= (bits
& 0x00040000U
) >> 18;
2768 uint32_t lo
= (bits
& 0x00000ffeU
) >> 1;
2770 return (lower_insn
& 0xd000U
) | (j1
<< 13) | (j2
<< 11) | lo
;
2773 // R_ARM_ABS8: S + A
2774 static inline typename
This::Status
2775 abs8(unsigned char *view
,
2776 const Sized_relobj
<32, big_endian
>* object
,
2777 const Symbol_value
<32>* psymval
)
2779 typedef typename
elfcpp::Swap
<8, big_endian
>::Valtype Valtype
;
2780 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2781 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2782 Valtype val
= elfcpp::Swap
<8, big_endian
>::readval(wv
);
2783 Reltype addend
= utils::sign_extend
<8>(val
);
2784 Reltype x
= psymval
->value(object
, addend
);
2785 val
= utils::bit_select(val
, x
, 0xffU
);
2786 elfcpp::Swap
<8, big_endian
>::writeval(wv
, val
);
2787 return (utils::has_signed_unsigned_overflow
<8>(x
)
2788 ? This::STATUS_OVERFLOW
2789 : This::STATUS_OKAY
);
2792 // R_ARM_THM_ABS5: S + A
2793 static inline typename
This::Status
2794 thm_abs5(unsigned char *view
,
2795 const Sized_relobj
<32, big_endian
>* object
,
2796 const Symbol_value
<32>* psymval
)
2798 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2799 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2800 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2801 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2802 Reltype addend
= (val
& 0x7e0U
) >> 6;
2803 Reltype x
= psymval
->value(object
, addend
);
2804 val
= utils::bit_select(val
, x
<< 6, 0x7e0U
);
2805 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2806 return (utils::has_overflow
<5>(x
)
2807 ? This::STATUS_OVERFLOW
2808 : This::STATUS_OKAY
);
2811 // R_ARM_ABS12: S + A
2812 static inline typename
This::Status
2813 abs12(unsigned char *view
,
2814 const Sized_relobj
<32, big_endian
>* object
,
2815 const Symbol_value
<32>* psymval
)
2817 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2818 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2819 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2820 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2821 Reltype addend
= val
& 0x0fffU
;
2822 Reltype x
= psymval
->value(object
, addend
);
2823 val
= utils::bit_select(val
, x
, 0x0fffU
);
2824 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2825 return (utils::has_overflow
<12>(x
)
2826 ? This::STATUS_OVERFLOW
2827 : This::STATUS_OKAY
);
2830 // R_ARM_ABS16: S + A
2831 static inline typename
This::Status
2832 abs16(unsigned char *view
,
2833 const Sized_relobj
<32, big_endian
>* object
,
2834 const Symbol_value
<32>* psymval
)
2836 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2837 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2838 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2839 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2840 Reltype addend
= utils::sign_extend
<16>(val
);
2841 Reltype x
= psymval
->value(object
, addend
);
2842 val
= utils::bit_select(val
, x
, 0xffffU
);
2843 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2844 return (utils::has_signed_unsigned_overflow
<16>(x
)
2845 ? This::STATUS_OVERFLOW
2846 : This::STATUS_OKAY
);
2849 // R_ARM_ABS32: (S + A) | T
2850 static inline typename
This::Status
2851 abs32(unsigned char *view
,
2852 const Sized_relobj
<32, big_endian
>* object
,
2853 const Symbol_value
<32>* psymval
,
2854 Arm_address thumb_bit
)
2856 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2857 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2858 Valtype addend
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2859 Valtype x
= psymval
->value(object
, addend
) | thumb_bit
;
2860 elfcpp::Swap
<32, big_endian
>::writeval(wv
, x
);
2861 return This::STATUS_OKAY
;
2864 // R_ARM_REL32: (S + A) | T - P
2865 static inline typename
This::Status
2866 rel32(unsigned char *view
,
2867 const Sized_relobj
<32, big_endian
>* object
,
2868 const Symbol_value
<32>* psymval
,
2869 Arm_address address
,
2870 Arm_address thumb_bit
)
2872 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2873 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2874 Valtype addend
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2875 Valtype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2876 elfcpp::Swap
<32, big_endian
>::writeval(wv
, x
);
2877 return This::STATUS_OKAY
;
2880 // R_ARM_THM_JUMP24: (S + A) | T - P
2881 static typename
This::Status
2882 thm_jump19(unsigned char *view
, const Arm_relobj
<big_endian
>* object
,
2883 const Symbol_value
<32>* psymval
, Arm_address address
,
2884 Arm_address thumb_bit
);
2886 // R_ARM_THM_JUMP6: S + A – P
2887 static inline typename
This::Status
2888 thm_jump6(unsigned char *view
,
2889 const Sized_relobj
<32, big_endian
>* object
,
2890 const Symbol_value
<32>* psymval
,
2891 Arm_address address
)
2893 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2894 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2895 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2896 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2897 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
2898 Reltype addend
= (((val
& 0x0200) >> 3) | ((val
& 0x00f8) >> 2));
2899 Reltype x
= (psymval
->value(object
, addend
) - address
);
2900 val
= (val
& 0xfd07) | ((x
& 0x0040) << 3) | ((val
& 0x003e) << 2);
2901 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2902 // CZB does only forward jumps.
2903 return ((x
> 0x007e)
2904 ? This::STATUS_OVERFLOW
2905 : This::STATUS_OKAY
);
2908 // R_ARM_THM_JUMP8: S + A – P
2909 static inline typename
This::Status
2910 thm_jump8(unsigned char *view
,
2911 const Sized_relobj
<32, big_endian
>* object
,
2912 const Symbol_value
<32>* psymval
,
2913 Arm_address address
)
2915 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2916 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2917 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2918 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2919 Reltype addend
= utils::sign_extend
<8>((val
& 0x00ff) << 1);
2920 Reltype x
= (psymval
->value(object
, addend
) - address
);
2921 elfcpp::Swap
<16, big_endian
>::writeval(wv
, (val
& 0xff00) | ((x
& 0x01fe) >> 1));
2922 return (utils::has_overflow
<8>(x
)
2923 ? This::STATUS_OVERFLOW
2924 : This::STATUS_OKAY
);
2927 // R_ARM_THM_JUMP11: S + A – P
2928 static inline typename
This::Status
2929 thm_jump11(unsigned char *view
,
2930 const Sized_relobj
<32, big_endian
>* object
,
2931 const Symbol_value
<32>* psymval
,
2932 Arm_address address
)
2934 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2935 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2936 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2937 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2938 Reltype addend
= utils::sign_extend
<11>((val
& 0x07ff) << 1);
2939 Reltype x
= (psymval
->value(object
, addend
) - address
);
2940 elfcpp::Swap
<16, big_endian
>::writeval(wv
, (val
& 0xf800) | ((x
& 0x0ffe) >> 1));
2941 return (utils::has_overflow
<11>(x
)
2942 ? This::STATUS_OVERFLOW
2943 : This::STATUS_OKAY
);
2946 // R_ARM_BASE_PREL: B(S) + A - P
2947 static inline typename
This::Status
2948 base_prel(unsigned char* view
,
2950 Arm_address address
)
2952 Base::rel32(view
, origin
- address
);
2956 // R_ARM_BASE_ABS: B(S) + A
2957 static inline typename
This::Status
2958 base_abs(unsigned char* view
,
2961 Base::rel32(view
, origin
);
2965 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
2966 static inline typename
This::Status
2967 got_brel(unsigned char* view
,
2968 typename
elfcpp::Swap
<32, big_endian
>::Valtype got_offset
)
2970 Base::rel32(view
, got_offset
);
2971 return This::STATUS_OKAY
;
2974 // R_ARM_GOT_PREL: GOT(S) + A - P
2975 static inline typename
This::Status
2976 got_prel(unsigned char *view
,
2977 Arm_address got_entry
,
2978 Arm_address address
)
2980 Base::rel32(view
, got_entry
- address
);
2981 return This::STATUS_OKAY
;
2984 // R_ARM_PREL: (S + A) | T - P
2985 static inline typename
This::Status
2986 prel31(unsigned char *view
,
2987 const Sized_relobj
<32, big_endian
>* object
,
2988 const Symbol_value
<32>* psymval
,
2989 Arm_address address
,
2990 Arm_address thumb_bit
)
2992 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2993 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2994 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2995 Valtype addend
= utils::sign_extend
<31>(val
);
2996 Valtype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2997 val
= utils::bit_select(val
, x
, 0x7fffffffU
);
2998 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2999 return (utils::has_overflow
<31>(x
) ?
3000 This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
3003 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3004 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3005 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3006 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3007 static inline typename
This::Status
3008 movw(unsigned char* view
,
3009 const Sized_relobj
<32, big_endian
>* object
,
3010 const Symbol_value
<32>* psymval
,
3011 Arm_address relative_address_base
,
3012 Arm_address thumb_bit
,
3013 bool check_overflow
)
3015 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3016 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3017 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3018 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
3019 Valtype x
= ((psymval
->value(object
, addend
) | thumb_bit
)
3020 - relative_address_base
);
3021 val
= This::insert_val_arm_movw_movt(val
, x
);
3022 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
3023 return ((check_overflow
&& utils::has_overflow
<16>(x
))
3024 ? This::STATUS_OVERFLOW
3025 : This::STATUS_OKAY
);
3028 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3029 // R_ARM_MOVT_PREL: S + A - P
3030 // R_ARM_MOVT_BREL: S + A - B(S)
3031 static inline typename
This::Status
3032 movt(unsigned char* view
,
3033 const Sized_relobj
<32, big_endian
>* object
,
3034 const Symbol_value
<32>* psymval
,
3035 Arm_address relative_address_base
)
3037 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3038 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3039 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3040 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
3041 Valtype x
= (psymval
->value(object
, addend
) - relative_address_base
) >> 16;
3042 val
= This::insert_val_arm_movw_movt(val
, x
);
3043 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
3044 // FIXME: IHI0044D says that we should check for overflow.
3045 return This::STATUS_OKAY
;
3048 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3049 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3050 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3051 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3052 static inline typename
This::Status
3053 thm_movw(unsigned char *view
,
3054 const Sized_relobj
<32, big_endian
>* object
,
3055 const Symbol_value
<32>* psymval
,
3056 Arm_address relative_address_base
,
3057 Arm_address thumb_bit
,
3058 bool check_overflow
)
3060 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3061 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
3062 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3063 Reltype val
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
3064 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3065 Reltype addend
= This::extract_thumb_movw_movt_addend(val
);
3067 (psymval
->value(object
, addend
) | thumb_bit
) - relative_address_base
;
3068 val
= This::insert_val_thumb_movw_movt(val
, x
);
3069 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
3070 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
3071 return ((check_overflow
&& utils::has_overflow
<16>(x
))
3072 ? This::STATUS_OVERFLOW
3073 : This::STATUS_OKAY
);
3076 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3077 // R_ARM_THM_MOVT_PREL: S + A - P
3078 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3079 static inline typename
This::Status
3080 thm_movt(unsigned char* view
,
3081 const Sized_relobj
<32, big_endian
>* object
,
3082 const Symbol_value
<32>* psymval
,
3083 Arm_address relative_address_base
)
3085 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3086 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
3087 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3088 Reltype val
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
3089 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3090 Reltype addend
= This::extract_thumb_movw_movt_addend(val
);
3091 Reltype x
= (psymval
->value(object
, addend
) - relative_address_base
) >> 16;
3092 val
= This::insert_val_thumb_movw_movt(val
, x
);
3093 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
3094 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
3095 return This::STATUS_OKAY
;
3098 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3099 static inline typename
This::Status
3100 thm_alu11(unsigned char* view
,
3101 const Sized_relobj
<32, big_endian
>* object
,
3102 const Symbol_value
<32>* psymval
,
3103 Arm_address address
,
3104 Arm_address thumb_bit
)
3106 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3107 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
3108 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3109 Reltype insn
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
3110 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3112 // 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
3113 // -----------------------------------------------------------------------
3114 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3115 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3116 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3117 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3118 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3119 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3121 // Determine a sign for the addend.
3122 const int sign
= ((insn
& 0xf8ef0000) == 0xf0ad0000
3123 || (insn
& 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3124 // Thumb2 addend encoding:
3125 // imm12 := i | imm3 | imm8
3126 int32_t addend
= (insn
& 0xff)
3127 | ((insn
& 0x00007000) >> 4)
3128 | ((insn
& 0x04000000) >> 15);
3129 // Apply a sign to the added.
3132 int32_t x
= (psymval
->value(object
, addend
) | thumb_bit
)
3133 - (address
& 0xfffffffc);
3134 Reltype val
= abs(x
);
3135 // Mask out the value and a distinct part of the ADD/SUB opcode
3136 // (bits 7:5 of opword).
3137 insn
= (insn
& 0xfb0f8f00)
3139 | ((val
& 0x700) << 4)
3140 | ((val
& 0x800) << 15);
3141 // Set the opcode according to whether the value to go in the
3142 // place is negative.
3146 elfcpp::Swap
<16, big_endian
>::writeval(wv
, insn
>> 16);
3147 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, insn
& 0xffff);
3148 return ((val
> 0xfff) ?
3149 This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
3152 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3153 static inline typename
This::Status
3154 thm_pc8(unsigned char* view
,
3155 const Sized_relobj
<32, big_endian
>* object
,
3156 const Symbol_value
<32>* psymval
,
3157 Arm_address address
)
3159 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3160 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
3161 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3162 Valtype insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
3163 Reltype addend
= ((insn
& 0x00ff) << 2);
3164 int32_t x
= (psymval
->value(object
, addend
) - (address
& 0xfffffffc));
3165 Reltype val
= abs(x
);
3166 insn
= (insn
& 0xff00) | ((val
& 0x03fc) >> 2);
3168 elfcpp::Swap
<16, big_endian
>::writeval(wv
, insn
);
3169 return ((val
> 0x03fc)
3170 ? This::STATUS_OVERFLOW
3171 : This::STATUS_OKAY
);
3174 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3175 static inline typename
This::Status
3176 thm_pc12(unsigned char* view
,
3177 const Sized_relobj
<32, big_endian
>* object
,
3178 const Symbol_value
<32>* psymval
,
3179 Arm_address address
)
3181 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3182 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
3183 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3184 Reltype insn
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
3185 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3186 // Determine a sign for the addend (positive if the U bit is 1).
3187 const int sign
= (insn
& 0x00800000) ? 1 : -1;
3188 int32_t addend
= (insn
& 0xfff);
3189 // Apply a sign to the added.
3192 int32_t x
= (psymval
->value(object
, addend
) - (address
& 0xfffffffc));
3193 Reltype val
= abs(x
);
3194 // Mask out and apply the value and the U bit.
3195 insn
= (insn
& 0xff7ff000) | (val
& 0xfff);
3196 // Set the U bit according to whether the value to go in the
3197 // place is positive.
3201 elfcpp::Swap
<16, big_endian
>::writeval(wv
, insn
>> 16);
3202 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, insn
& 0xffff);
3203 return ((val
> 0xfff) ?
3204 This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
3208 static inline typename
This::Status
3209 v4bx(const Relocate_info
<32, big_endian
>* relinfo
,
3210 unsigned char *view
,
3211 const Arm_relobj
<big_endian
>* object
,
3212 const Arm_address address
,
3213 const bool is_interworking
)
3216 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3217 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3218 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3220 // Ensure that we have a BX instruction.
3221 gold_assert((val
& 0x0ffffff0) == 0x012fff10);
3222 const uint32_t reg
= (val
& 0xf);
3223 if (is_interworking
&& reg
!= 0xf)
3225 Stub_table
<big_endian
>* stub_table
=
3226 object
->stub_table(relinfo
->data_shndx
);
3227 gold_assert(stub_table
!= NULL
);
3229 Arm_v4bx_stub
* stub
= stub_table
->find_arm_v4bx_stub(reg
);
3230 gold_assert(stub
!= NULL
);
3232 int32_t veneer_address
=
3233 stub_table
->address() + stub
->offset() - 8 - address
;
3234 gold_assert((veneer_address
<= ARM_MAX_FWD_BRANCH_OFFSET
)
3235 && (veneer_address
>= ARM_MAX_BWD_BRANCH_OFFSET
));
3236 // Replace with a branch to veneer (B <addr>)
3237 val
= (val
& 0xf0000000) | 0x0a000000
3238 | ((veneer_address
>> 2) & 0x00ffffff);
3242 // Preserve Rm (lowest four bits) and the condition code
3243 // (highest four bits). Other bits encode MOV PC,Rm.
3244 val
= (val
& 0xf000000f) | 0x01a0f000;
3246 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
3247 return This::STATUS_OKAY
;
3250 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3251 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3252 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3253 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3254 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3255 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3256 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3257 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3258 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3259 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3260 static inline typename
This::Status
3261 arm_grp_alu(unsigned char* view
,
3262 const Sized_relobj
<32, big_endian
>* object
,
3263 const Symbol_value
<32>* psymval
,
3265 Arm_address address
,
3266 Arm_address thumb_bit
,
3267 bool check_overflow
)
3269 gold_assert(group
>= 0 && group
< 3);
3270 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3271 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3272 Valtype insn
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3274 // ALU group relocations are allowed only for the ADD/SUB instructions.
3275 // (0x00800000 - ADD, 0x00400000 - SUB)
3276 const Valtype opcode
= insn
& 0x01e00000;
3277 if (opcode
!= 0x00800000 && opcode
!= 0x00400000)
3278 return This::STATUS_BAD_RELOC
;
3280 // Determine a sign for the addend.
3281 const int sign
= (opcode
== 0x00800000) ? 1 : -1;
3282 // shifter = rotate_imm * 2
3283 const uint32_t shifter
= (insn
& 0xf00) >> 7;
3284 // Initial addend value.
3285 int32_t addend
= insn
& 0xff;
3286 // Rotate addend right by shifter.
3287 addend
= (addend
>> shifter
) | (addend
<< (32 - shifter
));
3288 // Apply a sign to the added.
3291 int32_t x
= ((psymval
->value(object
, addend
) | thumb_bit
) - address
);
3292 Valtype gn
= Arm_relocate_functions::calc_grp_gn(abs(x
), group
);
3293 // Check for overflow if required
3295 && (Arm_relocate_functions::calc_grp_residual(abs(x
), group
) != 0))
3296 return This::STATUS_OVERFLOW
;
3298 // Mask out the value and the ADD/SUB part of the opcode; take care
3299 // not to destroy the S bit.
3301 // Set the opcode according to whether the value to go in the
3302 // place is negative.
3303 insn
|= ((x
< 0) ? 0x00400000 : 0x00800000);
3304 // Encode the offset (encoded Gn).
3307 elfcpp::Swap
<32, big_endian
>::writeval(wv
, insn
);
3308 return This::STATUS_OKAY
;
3311 // R_ARM_LDR_PC_G0: S + A - P
3312 // R_ARM_LDR_PC_G1: S + A - P
3313 // R_ARM_LDR_PC_G2: S + A - P
3314 // R_ARM_LDR_SB_G0: S + A - B(S)
3315 // R_ARM_LDR_SB_G1: S + A - B(S)
3316 // R_ARM_LDR_SB_G2: S + A - B(S)
3317 static inline typename
This::Status
3318 arm_grp_ldr(unsigned char* view
,
3319 const Sized_relobj
<32, big_endian
>* object
,
3320 const Symbol_value
<32>* psymval
,
3322 Arm_address address
)
3324 gold_assert(group
>= 0 && group
< 3);
3325 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3326 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3327 Valtype insn
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3329 const int sign
= (insn
& 0x00800000) ? 1 : -1;
3330 int32_t addend
= (insn
& 0xfff) * sign
;
3331 int32_t x
= (psymval
->value(object
, addend
) - address
);
3332 // Calculate the relevant G(n-1) value to obtain this stage residual.
3334 Arm_relocate_functions::calc_grp_residual(abs(x
), group
- 1);
3335 if (residual
>= 0x1000)
3336 return This::STATUS_OVERFLOW
;
3338 // Mask out the value and U bit.
3340 // Set the U bit for non-negative values.
3345 elfcpp::Swap
<32, big_endian
>::writeval(wv
, insn
);
3346 return This::STATUS_OKAY
;
3349 // R_ARM_LDRS_PC_G0: S + A - P
3350 // R_ARM_LDRS_PC_G1: S + A - P
3351 // R_ARM_LDRS_PC_G2: S + A - P
3352 // R_ARM_LDRS_SB_G0: S + A - B(S)
3353 // R_ARM_LDRS_SB_G1: S + A - B(S)
3354 // R_ARM_LDRS_SB_G2: S + A - B(S)
3355 static inline typename
This::Status
3356 arm_grp_ldrs(unsigned char* view
,
3357 const Sized_relobj
<32, big_endian
>* object
,
3358 const Symbol_value
<32>* psymval
,
3360 Arm_address address
)
3362 gold_assert(group
>= 0 && group
< 3);
3363 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3364 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3365 Valtype insn
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3367 const int sign
= (insn
& 0x00800000) ? 1 : -1;
3368 int32_t addend
= (((insn
& 0xf00) >> 4) + (insn
& 0xf)) * sign
;
3369 int32_t x
= (psymval
->value(object
, addend
) - address
);
3370 // Calculate the relevant G(n-1) value to obtain this stage residual.
3372 Arm_relocate_functions::calc_grp_residual(abs(x
), group
- 1);
3373 if (residual
>= 0x100)
3374 return This::STATUS_OVERFLOW
;
3376 // Mask out the value and U bit.
3378 // Set the U bit for non-negative values.
3381 insn
|= ((residual
& 0xf0) << 4) | (residual
& 0xf);
3383 elfcpp::Swap
<32, big_endian
>::writeval(wv
, insn
);
3384 return This::STATUS_OKAY
;
3387 // R_ARM_LDC_PC_G0: S + A - P
3388 // R_ARM_LDC_PC_G1: S + A - P
3389 // R_ARM_LDC_PC_G2: S + A - P
3390 // R_ARM_LDC_SB_G0: S + A - B(S)
3391 // R_ARM_LDC_SB_G1: S + A - B(S)
3392 // R_ARM_LDC_SB_G2: S + A - B(S)
3393 static inline typename
This::Status
3394 arm_grp_ldc(unsigned char* view
,
3395 const Sized_relobj
<32, big_endian
>* object
,
3396 const Symbol_value
<32>* psymval
,
3398 Arm_address address
)
3400 gold_assert(group
>= 0 && group
< 3);
3401 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3402 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3403 Valtype insn
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3405 const int sign
= (insn
& 0x00800000) ? 1 : -1;
3406 int32_t addend
= ((insn
& 0xff) << 2) * sign
;
3407 int32_t x
= (psymval
->value(object
, addend
) - address
);
3408 // Calculate the relevant G(n-1) value to obtain this stage residual.
3410 Arm_relocate_functions::calc_grp_residual(abs(x
), group
- 1);
3411 if ((residual
& 0x3) != 0 || residual
>= 0x400)
3412 return This::STATUS_OVERFLOW
;
3414 // Mask out the value and U bit.
3416 // Set the U bit for non-negative values.
3419 insn
|= (residual
>> 2);
3421 elfcpp::Swap
<32, big_endian
>::writeval(wv
, insn
);
3422 return This::STATUS_OKAY
;
3426 // Relocate ARM long branches. This handles relocation types
3427 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3428 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3429 // undefined and we do not use PLT in this relocation. In such a case,
3430 // the branch is converted into an NOP.
3432 template<bool big_endian
>
3433 typename Arm_relocate_functions
<big_endian
>::Status
3434 Arm_relocate_functions
<big_endian
>::arm_branch_common(
3435 unsigned int r_type
,
3436 const Relocate_info
<32, big_endian
>* relinfo
,
3437 unsigned char *view
,
3438 const Sized_symbol
<32>* gsym
,
3439 const Arm_relobj
<big_endian
>* object
,
3441 const Symbol_value
<32>* psymval
,
3442 Arm_address address
,
3443 Arm_address thumb_bit
,
3444 bool is_weakly_undefined_without_plt
)
3446 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
3447 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3448 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
3450 bool insn_is_b
= (((val
>> 28) & 0xf) <= 0xe)
3451 && ((val
& 0x0f000000UL
) == 0x0a000000UL
);
3452 bool insn_is_uncond_bl
= (val
& 0xff000000UL
) == 0xeb000000UL
;
3453 bool insn_is_cond_bl
= (((val
>> 28) & 0xf) < 0xe)
3454 && ((val
& 0x0f000000UL
) == 0x0b000000UL
);
3455 bool insn_is_blx
= (val
& 0xfe000000UL
) == 0xfa000000UL
;
3456 bool insn_is_any_branch
= (val
& 0x0e000000UL
) == 0x0a000000UL
;
3458 // Check that the instruction is valid.
3459 if (r_type
== elfcpp::R_ARM_CALL
)
3461 if (!insn_is_uncond_bl
&& !insn_is_blx
)
3462 return This::STATUS_BAD_RELOC
;
3464 else if (r_type
== elfcpp::R_ARM_JUMP24
)
3466 if (!insn_is_b
&& !insn_is_cond_bl
)
3467 return This::STATUS_BAD_RELOC
;
3469 else if (r_type
== elfcpp::R_ARM_PLT32
)
3471 if (!insn_is_any_branch
)
3472 return This::STATUS_BAD_RELOC
;
3474 else if (r_type
== elfcpp::R_ARM_XPC25
)
3476 // FIXME: AAELF document IH0044C does not say much about it other
3477 // than it being obsolete.
3478 if (!insn_is_any_branch
)
3479 return This::STATUS_BAD_RELOC
;
3484 // A branch to an undefined weak symbol is turned into a jump to
3485 // the next instruction unless a PLT entry will be created.
3486 // Do the same for local undefined symbols.
3487 // The jump to the next instruction is optimized as a NOP depending
3488 // on the architecture.
3489 const Target_arm
<big_endian
>* arm_target
=
3490 Target_arm
<big_endian
>::default_target();
3491 if (is_weakly_undefined_without_plt
)
3493 Valtype cond
= val
& 0xf0000000U
;
3494 if (arm_target
->may_use_arm_nop())
3495 val
= cond
| 0x0320f000;
3497 val
= cond
| 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3498 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
3499 return This::STATUS_OKAY
;
3502 Valtype addend
= utils::sign_extend
<26>(val
<< 2);
3503 Valtype branch_target
= psymval
->value(object
, addend
);
3504 int32_t branch_offset
= branch_target
- address
;
3506 // We need a stub if the branch offset is too large or if we need
3508 bool may_use_blx
= arm_target
->may_use_blx();
3509 Reloc_stub
* stub
= NULL
;
3510 if ((branch_offset
> ARM_MAX_FWD_BRANCH_OFFSET
)
3511 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
)
3512 || ((thumb_bit
!= 0) && !(may_use_blx
&& r_type
== elfcpp::R_ARM_CALL
)))
3514 Stub_type stub_type
=
3515 Reloc_stub::stub_type_for_reloc(r_type
, address
, branch_target
,
3517 if (stub_type
!= arm_stub_none
)
3519 Stub_table
<big_endian
>* stub_table
=
3520 object
->stub_table(relinfo
->data_shndx
);
3521 gold_assert(stub_table
!= NULL
);
3523 Reloc_stub::Key
stub_key(stub_type
, gsym
, object
, r_sym
, addend
);
3524 stub
= stub_table
->find_reloc_stub(stub_key
);
3525 gold_assert(stub
!= NULL
);
3526 thumb_bit
= stub
->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3527 branch_target
= stub_table
->address() + stub
->offset() + addend
;
3528 branch_offset
= branch_target
- address
;
3529 gold_assert((branch_offset
<= ARM_MAX_FWD_BRANCH_OFFSET
)
3530 && (branch_offset
>= ARM_MAX_BWD_BRANCH_OFFSET
));
3534 // At this point, if we still need to switch mode, the instruction
3535 // must either be a BLX or a BL that can be converted to a BLX.
3539 gold_assert(may_use_blx
&& r_type
== elfcpp::R_ARM_CALL
);
3540 val
= (val
& 0xffffff) | 0xfa000000 | ((branch_offset
& 2) << 23);
3543 val
= utils::bit_select(val
, (branch_offset
>> 2), 0xffffffUL
);
3544 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
3545 return (utils::has_overflow
<26>(branch_offset
)
3546 ? This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
3549 // Relocate THUMB long branches. This handles relocation types
3550 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3551 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3552 // undefined and we do not use PLT in this relocation. In such a case,
3553 // the branch is converted into an NOP.
3555 template<bool big_endian
>
3556 typename Arm_relocate_functions
<big_endian
>::Status
3557 Arm_relocate_functions
<big_endian
>::thumb_branch_common(
3558 unsigned int r_type
,
3559 const Relocate_info
<32, big_endian
>* relinfo
,
3560 unsigned char *view
,
3561 const Sized_symbol
<32>* gsym
,
3562 const Arm_relobj
<big_endian
>* object
,
3564 const Symbol_value
<32>* psymval
,
3565 Arm_address address
,
3566 Arm_address thumb_bit
,
3567 bool is_weakly_undefined_without_plt
)
3569 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3570 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3571 uint32_t upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
3572 uint32_t lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3574 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3576 bool is_bl_insn
= (lower_insn
& 0x1000U
) == 0x1000U
;
3577 bool is_blx_insn
= (lower_insn
& 0x1000U
) == 0x0000U
;
3579 // Check that the instruction is valid.
3580 if (r_type
== elfcpp::R_ARM_THM_CALL
)
3582 if (!is_bl_insn
&& !is_blx_insn
)
3583 return This::STATUS_BAD_RELOC
;
3585 else if (r_type
== elfcpp::R_ARM_THM_JUMP24
)
3587 // This cannot be a BLX.
3589 return This::STATUS_BAD_RELOC
;
3591 else if (r_type
== elfcpp::R_ARM_THM_XPC22
)
3593 // Check for Thumb to Thumb call.
3595 return This::STATUS_BAD_RELOC
;
3598 gold_warning(_("%s: Thumb BLX instruction targets "
3599 "thumb function '%s'."),
3600 object
->name().c_str(),
3601 (gsym
? gsym
->name() : "(local)"));
3602 // Convert BLX to BL.
3603 lower_insn
|= 0x1000U
;
3609 // A branch to an undefined weak symbol is turned into a jump to
3610 // the next instruction unless a PLT entry will be created.
3611 // The jump to the next instruction is optimized as a NOP.W for
3612 // Thumb-2 enabled architectures.
3613 const Target_arm
<big_endian
>* arm_target
=
3614 Target_arm
<big_endian
>::default_target();
3615 if (is_weakly_undefined_without_plt
)
3617 if (arm_target
->may_use_thumb2_nop())
3619 elfcpp::Swap
<16, big_endian
>::writeval(wv
, 0xf3af);
3620 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, 0x8000);
3624 elfcpp::Swap
<16, big_endian
>::writeval(wv
, 0xe000);
3625 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, 0xbf00);
3627 return This::STATUS_OKAY
;
3630 int32_t addend
= This::thumb32_branch_offset(upper_insn
, lower_insn
);
3631 Arm_address branch_target
= psymval
->value(object
, addend
);
3632 int32_t branch_offset
= branch_target
- address
;
3634 // We need a stub if the branch offset is too large or if we need
3636 bool may_use_blx
= arm_target
->may_use_blx();
3637 bool thumb2
= arm_target
->using_thumb2();
3639 && (branch_offset
> THM_MAX_FWD_BRANCH_OFFSET
3640 || (branch_offset
< THM_MAX_BWD_BRANCH_OFFSET
)))
3642 && (branch_offset
> THM2_MAX_FWD_BRANCH_OFFSET
3643 || (branch_offset
< THM2_MAX_BWD_BRANCH_OFFSET
)))
3644 || ((thumb_bit
== 0)
3645 && (((r_type
== elfcpp::R_ARM_THM_CALL
) && !may_use_blx
)
3646 || r_type
== elfcpp::R_ARM_THM_JUMP24
)))
3648 Stub_type stub_type
=
3649 Reloc_stub::stub_type_for_reloc(r_type
, address
, branch_target
,
3651 if (stub_type
!= arm_stub_none
)
3653 Stub_table
<big_endian
>* stub_table
=
3654 object
->stub_table(relinfo
->data_shndx
);
3655 gold_assert(stub_table
!= NULL
);
3657 Reloc_stub::Key
stub_key(stub_type
, gsym
, object
, r_sym
, addend
);
3658 Reloc_stub
* stub
= stub_table
->find_reloc_stub(stub_key
);
3659 gold_assert(stub
!= NULL
);
3660 thumb_bit
= stub
->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3661 branch_target
= stub_table
->address() + stub
->offset() + addend
;
3662 branch_offset
= branch_target
- address
;
3666 // At this point, if we still need to switch mode, the instruction
3667 // must either be a BLX or a BL that can be converted to a BLX.
3670 gold_assert(may_use_blx
3671 && (r_type
== elfcpp::R_ARM_THM_CALL
3672 || r_type
== elfcpp::R_ARM_THM_XPC22
));
3673 // Make sure this is a BLX.
3674 lower_insn
&= ~0x1000U
;
3678 // Make sure this is a BL.
3679 lower_insn
|= 0x1000U
;
3682 if ((lower_insn
& 0x5000U
) == 0x4000U
)
3683 // For a BLX instruction, make sure that the relocation is rounded up
3684 // to a word boundary. This follows the semantics of the instruction
3685 // which specifies that bit 1 of the target address will come from bit
3686 // 1 of the base address.
3687 branch_offset
= (branch_offset
+ 2) & ~3;
3689 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
3690 // We use the Thumb-2 encoding, which is safe even if dealing with
3691 // a Thumb-1 instruction by virtue of our overflow check above. */
3692 upper_insn
= This::thumb32_branch_upper(upper_insn
, branch_offset
);
3693 lower_insn
= This::thumb32_branch_lower(lower_insn
, branch_offset
);
3695 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
3696 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
3699 ? utils::has_overflow
<25>(branch_offset
)
3700 : utils::has_overflow
<23>(branch_offset
))
3701 ? This::STATUS_OVERFLOW
3702 : This::STATUS_OKAY
);
3705 // Relocate THUMB-2 long conditional branches.
3706 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3707 // undefined and we do not use PLT in this relocation. In such a case,
3708 // the branch is converted into an NOP.
3710 template<bool big_endian
>
3711 typename Arm_relocate_functions
<big_endian
>::Status
3712 Arm_relocate_functions
<big_endian
>::thm_jump19(
3713 unsigned char *view
,
3714 const Arm_relobj
<big_endian
>* object
,
3715 const Symbol_value
<32>* psymval
,
3716 Arm_address address
,
3717 Arm_address thumb_bit
)
3719 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3720 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3721 uint32_t upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
3722 uint32_t lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3723 int32_t addend
= This::thumb32_cond_branch_offset(upper_insn
, lower_insn
);
3725 Arm_address branch_target
= psymval
->value(object
, addend
);
3726 int32_t branch_offset
= branch_target
- address
;
3728 // ??? Should handle interworking? GCC might someday try to
3729 // use this for tail calls.
3730 // FIXME: We do support thumb entry to PLT yet.
3733 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
3734 return This::STATUS_BAD_RELOC
;
3737 // Put RELOCATION back into the insn.
3738 upper_insn
= This::thumb32_cond_branch_upper(upper_insn
, branch_offset
);
3739 lower_insn
= This::thumb32_cond_branch_lower(lower_insn
, branch_offset
);
3741 // Put the relocated value back in the object file:
3742 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
3743 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
3745 return (utils::has_overflow
<21>(branch_offset
)
3746 ? This::STATUS_OVERFLOW
3747 : This::STATUS_OKAY
);
3750 // Get the GOT section, creating it if necessary.
3752 template<bool big_endian
>
3753 Output_data_got
<32, big_endian
>*
3754 Target_arm
<big_endian
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
3756 if (this->got_
== NULL
)
3758 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
3760 this->got_
= new Output_data_got
<32, big_endian
>();
3763 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
3765 | elfcpp::SHF_WRITE
),
3766 this->got_
, false, true, true,
3769 // The old GNU linker creates a .got.plt section. We just
3770 // create another set of data in the .got section. Note that we
3771 // always create a PLT if we create a GOT, although the PLT
3773 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
3774 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
3776 | elfcpp::SHF_WRITE
),
3777 this->got_plt_
, false, false,
3780 // The first three entries are reserved.
3781 this->got_plt_
->set_current_data_size(3 * 4);
3783 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3784 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
3785 Symbol_table::PREDEFINED
,
3787 0, 0, elfcpp::STT_OBJECT
,
3789 elfcpp::STV_HIDDEN
, 0,
3795 // Get the dynamic reloc section, creating it if necessary.
3797 template<bool big_endian
>
3798 typename Target_arm
<big_endian
>::Reloc_section
*
3799 Target_arm
<big_endian
>::rel_dyn_section(Layout
* layout
)
3801 if (this->rel_dyn_
== NULL
)
3803 gold_assert(layout
!= NULL
);
3804 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
3805 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
3806 elfcpp::SHF_ALLOC
, this->rel_dyn_
, true,
3807 false, false, false);
3809 return this->rel_dyn_
;
3812 // Insn_template methods.
3814 // Return byte size of an instruction template.
3817 Insn_template::size() const
3819 switch (this->type())
3822 case THUMB16_SPECIAL_TYPE
:
3833 // Return alignment of an instruction template.
3836 Insn_template::alignment() const
3838 switch (this->type())
3841 case THUMB16_SPECIAL_TYPE
:
3852 // Stub_template methods.
3854 Stub_template::Stub_template(
3855 Stub_type type
, const Insn_template
* insns
,
3857 : type_(type
), insns_(insns
), insn_count_(insn_count
), alignment_(1),
3858 entry_in_thumb_mode_(false), relocs_()
3862 // Compute byte size and alignment of stub template.
3863 for (size_t i
= 0; i
< insn_count
; i
++)
3865 unsigned insn_alignment
= insns
[i
].alignment();
3866 size_t insn_size
= insns
[i
].size();
3867 gold_assert((offset
& (insn_alignment
- 1)) == 0);
3868 this->alignment_
= std::max(this->alignment_
, insn_alignment
);
3869 switch (insns
[i
].type())
3871 case Insn_template::THUMB16_TYPE
:
3872 case Insn_template::THUMB16_SPECIAL_TYPE
:
3874 this->entry_in_thumb_mode_
= true;
3877 case Insn_template::THUMB32_TYPE
:
3878 if (insns
[i
].r_type() != elfcpp::R_ARM_NONE
)
3879 this->relocs_
.push_back(Reloc(i
, offset
));
3881 this->entry_in_thumb_mode_
= true;
3884 case Insn_template::ARM_TYPE
:
3885 // Handle cases where the target is encoded within the
3887 if (insns
[i
].r_type() == elfcpp::R_ARM_JUMP24
)
3888 this->relocs_
.push_back(Reloc(i
, offset
));
3891 case Insn_template::DATA_TYPE
:
3892 // Entry point cannot be data.
3893 gold_assert(i
!= 0);
3894 this->relocs_
.push_back(Reloc(i
, offset
));
3900 offset
+= insn_size
;
3902 this->size_
= offset
;
3907 // Template to implement do_write for a specific target endianity.
3909 template<bool big_endian
>
3911 Stub::do_fixed_endian_write(unsigned char* view
, section_size_type view_size
)
3913 const Stub_template
* stub_template
= this->stub_template();
3914 const Insn_template
* insns
= stub_template
->insns();
3916 // FIXME: We do not handle BE8 encoding yet.
3917 unsigned char* pov
= view
;
3918 for (size_t i
= 0; i
< stub_template
->insn_count(); i
++)
3920 switch (insns
[i
].type())
3922 case Insn_template::THUMB16_TYPE
:
3923 elfcpp::Swap
<16, big_endian
>::writeval(pov
, insns
[i
].data() & 0xffff);
3925 case Insn_template::THUMB16_SPECIAL_TYPE
:
3926 elfcpp::Swap
<16, big_endian
>::writeval(
3928 this->thumb16_special(i
));
3930 case Insn_template::THUMB32_TYPE
:
3932 uint32_t hi
= (insns
[i
].data() >> 16) & 0xffff;
3933 uint32_t lo
= insns
[i
].data() & 0xffff;
3934 elfcpp::Swap
<16, big_endian
>::writeval(pov
, hi
);
3935 elfcpp::Swap
<16, big_endian
>::writeval(pov
+ 2, lo
);
3938 case Insn_template::ARM_TYPE
:
3939 case Insn_template::DATA_TYPE
:
3940 elfcpp::Swap
<32, big_endian
>::writeval(pov
, insns
[i
].data());
3945 pov
+= insns
[i
].size();
3947 gold_assert(static_cast<section_size_type
>(pov
- view
) == view_size
);
3950 // Reloc_stub::Key methods.
3952 // Dump a Key as a string for debugging.
3955 Reloc_stub::Key::name() const
3957 if (this->r_sym_
== invalid_index
)
3959 // Global symbol key name
3960 // <stub-type>:<symbol name>:<addend>.
3961 const std::string sym_name
= this->u_
.symbol
->name();
3962 // We need to print two hex number and two colons. So just add 100 bytes
3963 // to the symbol name size.
3964 size_t len
= sym_name
.size() + 100;
3965 char* buffer
= new char[len
];
3966 int c
= snprintf(buffer
, len
, "%d:%s:%x", this->stub_type_
,
3967 sym_name
.c_str(), this->addend_
);
3968 gold_assert(c
> 0 && c
< static_cast<int>(len
));
3970 return std::string(buffer
);
3974 // local symbol key name
3975 // <stub-type>:<object>:<r_sym>:<addend>.
3976 const size_t len
= 200;
3978 int c
= snprintf(buffer
, len
, "%d:%p:%u:%x", this->stub_type_
,
3979 this->u_
.relobj
, this->r_sym_
, this->addend_
);
3980 gold_assert(c
> 0 && c
< static_cast<int>(len
));
3981 return std::string(buffer
);
3985 // Reloc_stub methods.
3987 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
3988 // LOCATION to DESTINATION.
3989 // This code is based on the arm_type_of_stub function in
3990 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
3994 Reloc_stub::stub_type_for_reloc(
3995 unsigned int r_type
,
3996 Arm_address location
,
3997 Arm_address destination
,
3998 bool target_is_thumb
)
4000 Stub_type stub_type
= arm_stub_none
;
4002 // This is a bit ugly but we want to avoid using a templated class for
4003 // big and little endianities.
4005 bool should_force_pic_veneer
;
4008 if (parameters
->target().is_big_endian())
4010 const Target_arm
<true>* big_endian_target
=
4011 Target_arm
<true>::default_target();
4012 may_use_blx
= big_endian_target
->may_use_blx();
4013 should_force_pic_veneer
= big_endian_target
->should_force_pic_veneer();
4014 thumb2
= big_endian_target
->using_thumb2();
4015 thumb_only
= big_endian_target
->using_thumb_only();
4019 const Target_arm
<false>* little_endian_target
=
4020 Target_arm
<false>::default_target();
4021 may_use_blx
= little_endian_target
->may_use_blx();
4022 should_force_pic_veneer
= little_endian_target
->should_force_pic_veneer();
4023 thumb2
= little_endian_target
->using_thumb2();
4024 thumb_only
= little_endian_target
->using_thumb_only();
4027 int64_t branch_offset
= (int64_t)destination
- location
;
4029 if (r_type
== elfcpp::R_ARM_THM_CALL
|| r_type
== elfcpp::R_ARM_THM_JUMP24
)
4031 // Handle cases where:
4032 // - this call goes too far (different Thumb/Thumb2 max
4034 // - it's a Thumb->Arm call and blx is not available, or it's a
4035 // Thumb->Arm branch (not bl). A stub is needed in this case.
4037 && (branch_offset
> THM_MAX_FWD_BRANCH_OFFSET
4038 || (branch_offset
< THM_MAX_BWD_BRANCH_OFFSET
)))
4040 && (branch_offset
> THM2_MAX_FWD_BRANCH_OFFSET
4041 || (branch_offset
< THM2_MAX_BWD_BRANCH_OFFSET
)))
4042 || ((!target_is_thumb
)
4043 && (((r_type
== elfcpp::R_ARM_THM_CALL
) && !may_use_blx
)
4044 || (r_type
== elfcpp::R_ARM_THM_JUMP24
))))
4046 if (target_is_thumb
)
4051 stub_type
= (parameters
->options().shared()
4052 || should_force_pic_veneer
)
4055 && (r_type
== elfcpp::R_ARM_THM_CALL
))
4056 // V5T and above. Stub starts with ARM code, so
4057 // we must be able to switch mode before
4058 // reaching it, which is only possible for 'bl'
4059 // (ie R_ARM_THM_CALL relocation).
4060 ? arm_stub_long_branch_any_thumb_pic
4061 // On V4T, use Thumb code only.
4062 : arm_stub_long_branch_v4t_thumb_thumb_pic
)
4066 && (r_type
== elfcpp::R_ARM_THM_CALL
))
4067 ? arm_stub_long_branch_any_any
// V5T and above.
4068 : arm_stub_long_branch_v4t_thumb_thumb
); // V4T.
4072 stub_type
= (parameters
->options().shared()
4073 || should_force_pic_veneer
)
4074 ? arm_stub_long_branch_thumb_only_pic
// PIC stub.
4075 : arm_stub_long_branch_thumb_only
; // non-PIC stub.
4082 // FIXME: We should check that the input section is from an
4083 // object that has interwork enabled.
4085 stub_type
= (parameters
->options().shared()
4086 || should_force_pic_veneer
)
4089 && (r_type
== elfcpp::R_ARM_THM_CALL
))
4090 ? arm_stub_long_branch_any_arm_pic
// V5T and above.
4091 : arm_stub_long_branch_v4t_thumb_arm_pic
) // V4T.
4095 && (r_type
== elfcpp::R_ARM_THM_CALL
))
4096 ? arm_stub_long_branch_any_any
// V5T and above.
4097 : arm_stub_long_branch_v4t_thumb_arm
); // V4T.
4099 // Handle v4t short branches.
4100 if ((stub_type
== arm_stub_long_branch_v4t_thumb_arm
)
4101 && (branch_offset
<= THM_MAX_FWD_BRANCH_OFFSET
)
4102 && (branch_offset
>= THM_MAX_BWD_BRANCH_OFFSET
))
4103 stub_type
= arm_stub_short_branch_v4t_thumb_arm
;
4107 else if (r_type
== elfcpp::R_ARM_CALL
4108 || r_type
== elfcpp::R_ARM_JUMP24
4109 || r_type
== elfcpp::R_ARM_PLT32
)
4111 if (target_is_thumb
)
4115 // FIXME: We should check that the input section is from an
4116 // object that has interwork enabled.
4118 // We have an extra 2-bytes reach because of
4119 // the mode change (bit 24 (H) of BLX encoding).
4120 if (branch_offset
> (ARM_MAX_FWD_BRANCH_OFFSET
+ 2)
4121 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
)
4122 || ((r_type
== elfcpp::R_ARM_CALL
) && !may_use_blx
)
4123 || (r_type
== elfcpp::R_ARM_JUMP24
)
4124 || (r_type
== elfcpp::R_ARM_PLT32
))
4126 stub_type
= (parameters
->options().shared()
4127 || should_force_pic_veneer
)
4130 ? arm_stub_long_branch_any_thumb_pic
// V5T and above.
4131 : arm_stub_long_branch_v4t_arm_thumb_pic
) // V4T stub.
4135 ? arm_stub_long_branch_any_any
// V5T and above.
4136 : arm_stub_long_branch_v4t_arm_thumb
); // V4T.
4142 if (branch_offset
> ARM_MAX_FWD_BRANCH_OFFSET
4143 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
))
4145 stub_type
= (parameters
->options().shared()
4146 || should_force_pic_veneer
)
4147 ? arm_stub_long_branch_any_arm_pic
// PIC stubs.
4148 : arm_stub_long_branch_any_any
; /// non-PIC.
4156 // Cortex_a8_stub methods.
4158 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4159 // I is the position of the instruction template in the stub template.
4162 Cortex_a8_stub::do_thumb16_special(size_t i
)
4164 // The only use of this is to copy condition code from a conditional
4165 // branch being worked around to the corresponding conditional branch in
4167 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4169 uint16_t data
= this->stub_template()->insns()[i
].data();
4170 gold_assert((data
& 0xff00U
) == 0xd000U
);
4171 data
|= ((this->original_insn_
>> 22) & 0xf) << 8;
4175 // Stub_factory methods.
4177 Stub_factory::Stub_factory()
4179 // The instruction template sequences are declared as static
4180 // objects and initialized first time the constructor runs.
4182 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4183 // to reach the stub if necessary.
4184 static const Insn_template elf32_arm_stub_long_branch_any_any
[] =
4186 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4187 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
4188 // dcd R_ARM_ABS32(X)
4191 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4193 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb
[] =
4195 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4196 Insn_template::arm_insn(0xe12fff1c), // bx ip
4197 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
4198 // dcd R_ARM_ABS32(X)
4201 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4202 static const Insn_template elf32_arm_stub_long_branch_thumb_only
[] =
4204 Insn_template::thumb16_insn(0xb401), // push {r0}
4205 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4206 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4207 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4208 Insn_template::thumb16_insn(0x4760), // bx ip
4209 Insn_template::thumb16_insn(0xbf00), // nop
4210 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
4211 // dcd R_ARM_ABS32(X)
4214 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4216 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb
[] =
4218 Insn_template::thumb16_insn(0x4778), // bx pc
4219 Insn_template::thumb16_insn(0x46c0), // nop
4220 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4221 Insn_template::arm_insn(0xe12fff1c), // bx ip
4222 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
4223 // dcd R_ARM_ABS32(X)
4226 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4228 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm
[] =
4230 Insn_template::thumb16_insn(0x4778), // bx pc
4231 Insn_template::thumb16_insn(0x46c0), // nop
4232 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4233 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
4234 // dcd R_ARM_ABS32(X)
4237 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4238 // one, when the destination is close enough.
4239 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm
[] =
4241 Insn_template::thumb16_insn(0x4778), // bx pc
4242 Insn_template::thumb16_insn(0x46c0), // nop
4243 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4246 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4247 // blx to reach the stub if necessary.
4248 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic
[] =
4250 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4251 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4252 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, -4),
4253 // dcd R_ARM_REL32(X-4)
4256 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4257 // blx to reach the stub if necessary. We can not add into pc;
4258 // it is not guaranteed to mode switch (different in ARMv6 and
4260 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic
[] =
4262 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4263 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4264 Insn_template::arm_insn(0xe12fff1c), // bx ip
4265 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
4266 // dcd R_ARM_REL32(X)
4269 // V4T ARM -> ARM long branch stub, PIC.
4270 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic
[] =
4272 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4273 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4274 Insn_template::arm_insn(0xe12fff1c), // bx ip
4275 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
4276 // dcd R_ARM_REL32(X)
4279 // V4T Thumb -> ARM long branch stub, PIC.
4280 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic
[] =
4282 Insn_template::thumb16_insn(0x4778), // bx pc
4283 Insn_template::thumb16_insn(0x46c0), // nop
4284 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4285 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4286 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, -4),
4287 // dcd R_ARM_REL32(X)
4290 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4292 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic
[] =
4294 Insn_template::thumb16_insn(0xb401), // push {r0}
4295 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4296 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4297 Insn_template::thumb16_insn(0x4484), // add ip, r0
4298 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4299 Insn_template::thumb16_insn(0x4760), // bx ip
4300 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 4),
4301 // dcd R_ARM_REL32(X)
4304 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4306 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic
[] =
4308 Insn_template::thumb16_insn(0x4778), // bx pc
4309 Insn_template::thumb16_insn(0x46c0), // nop
4310 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4311 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4312 Insn_template::arm_insn(0xe12fff1c), // bx ip
4313 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
4314 // dcd R_ARM_REL32(X)
4317 // Cortex-A8 erratum-workaround stubs.
4319 // Stub used for conditional branches (which may be beyond +/-1MB away,
4320 // so we can't use a conditional branch to reach this stub).
4327 static const Insn_template elf32_arm_stub_a8_veneer_b_cond
[] =
4329 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4330 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4331 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4335 // Stub used for b.w and bl.w instructions.
4337 static const Insn_template elf32_arm_stub_a8_veneer_b
[] =
4339 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4342 static const Insn_template elf32_arm_stub_a8_veneer_bl
[] =
4344 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4347 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4348 // instruction (which switches to ARM mode) to point to this stub. Jump to
4349 // the real destination using an ARM-mode branch.
4350 static const Insn_template elf32_arm_stub_a8_veneer_blx
[] =
4352 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4355 // Stub used to provide an interworking for R_ARM_V4BX relocation
4356 // (bx r[n] instruction).
4357 static const Insn_template elf32_arm_stub_v4_veneer_bx
[] =
4359 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4360 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4361 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4364 // Fill in the stub template look-up table. Stub templates are constructed
4365 // per instance of Stub_factory for fast look-up without locking
4366 // in a thread-enabled environment.
4368 this->stub_templates_
[arm_stub_none
] =
4369 new Stub_template(arm_stub_none
, NULL
, 0);
4371 #define DEF_STUB(x) \
4375 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4376 Stub_type type = arm_stub_##x; \
4377 this->stub_templates_[type] = \
4378 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4386 // Stub_table methods.
4388 // Removel all Cortex-A8 stub.
4390 template<bool big_endian
>
4392 Stub_table
<big_endian
>::remove_all_cortex_a8_stubs()
4394 for (Cortex_a8_stub_list::iterator p
= this->cortex_a8_stubs_
.begin();
4395 p
!= this->cortex_a8_stubs_
.end();
4398 this->cortex_a8_stubs_
.clear();
4401 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4403 template<bool big_endian
>
4405 Stub_table
<big_endian
>::relocate_stub(
4407 const Relocate_info
<32, big_endian
>* relinfo
,
4408 Target_arm
<big_endian
>* arm_target
,
4409 Output_section
* output_section
,
4410 unsigned char* view
,
4411 Arm_address address
,
4412 section_size_type view_size
)
4414 const Stub_template
* stub_template
= stub
->stub_template();
4415 if (stub_template
->reloc_count() != 0)
4417 // Adjust view to cover the stub only.
4418 section_size_type offset
= stub
->offset();
4419 section_size_type stub_size
= stub_template
->size();
4420 gold_assert(offset
+ stub_size
<= view_size
);
4422 arm_target
->relocate_stub(stub
, relinfo
, output_section
, view
+ offset
,
4423 address
+ offset
, stub_size
);
4427 // Relocate all stubs in this stub table.
4429 template<bool big_endian
>
4431 Stub_table
<big_endian
>::relocate_stubs(
4432 const Relocate_info
<32, big_endian
>* relinfo
,
4433 Target_arm
<big_endian
>* arm_target
,
4434 Output_section
* output_section
,
4435 unsigned char* view
,
4436 Arm_address address
,
4437 section_size_type view_size
)
4439 // If we are passed a view bigger than the stub table's. we need to
4441 gold_assert(address
== this->address()
4443 == static_cast<section_size_type
>(this->data_size())));
4445 // Relocate all relocation stubs.
4446 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
4447 p
!= this->reloc_stubs_
.end();
4449 this->relocate_stub(p
->second
, relinfo
, arm_target
, output_section
, view
,
4450 address
, view_size
);
4452 // Relocate all Cortex-A8 stubs.
4453 for (Cortex_a8_stub_list::iterator p
= this->cortex_a8_stubs_
.begin();
4454 p
!= this->cortex_a8_stubs_
.end();
4456 this->relocate_stub(p
->second
, relinfo
, arm_target
, output_section
, view
,
4457 address
, view_size
);
4459 // Relocate all ARM V4BX stubs.
4460 for (Arm_v4bx_stub_list::iterator p
= this->arm_v4bx_stubs_
.begin();
4461 p
!= this->arm_v4bx_stubs_
.end();
4465 this->relocate_stub(*p
, relinfo
, arm_target
, output_section
, view
,
4466 address
, view_size
);
4470 // Write out the stubs to file.
4472 template<bool big_endian
>
4474 Stub_table
<big_endian
>::do_write(Output_file
* of
)
4476 off_t offset
= this->offset();
4477 const section_size_type oview_size
=
4478 convert_to_section_size_type(this->data_size());
4479 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
4481 // Write relocation stubs.
4482 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
4483 p
!= this->reloc_stubs_
.end();
4486 Reloc_stub
* stub
= p
->second
;
4487 Arm_address address
= this->address() + stub
->offset();
4489 == align_address(address
,
4490 stub
->stub_template()->alignment()));
4491 stub
->write(oview
+ stub
->offset(), stub
->stub_template()->size(),
4495 // Write Cortex-A8 stubs.
4496 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
4497 p
!= this->cortex_a8_stubs_
.end();
4500 Cortex_a8_stub
* stub
= p
->second
;
4501 Arm_address address
= this->address() + stub
->offset();
4503 == align_address(address
,
4504 stub
->stub_template()->alignment()));
4505 stub
->write(oview
+ stub
->offset(), stub
->stub_template()->size(),
4509 // Write ARM V4BX relocation stubs.
4510 for (Arm_v4bx_stub_list::const_iterator p
= this->arm_v4bx_stubs_
.begin();
4511 p
!= this->arm_v4bx_stubs_
.end();
4517 Arm_address address
= this->address() + (*p
)->offset();
4519 == align_address(address
,
4520 (*p
)->stub_template()->alignment()));
4521 (*p
)->write(oview
+ (*p
)->offset(), (*p
)->stub_template()->size(),
4525 of
->write_output_view(this->offset(), oview_size
, oview
);
4528 // Update the data size and address alignment of the stub table at the end
4529 // of a relaxation pass. Return true if either the data size or the
4530 // alignment changed in this relaxation pass.
4532 template<bool big_endian
>
4534 Stub_table
<big_endian
>::update_data_size_and_addralign()
4537 unsigned addralign
= 1;
4539 // Go over all stubs in table to compute data size and address alignment.
4541 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
4542 p
!= this->reloc_stubs_
.end();
4545 const Stub_template
* stub_template
= p
->second
->stub_template();
4546 addralign
= std::max(addralign
, stub_template
->alignment());
4547 size
= (align_address(size
, stub_template
->alignment())
4548 + stub_template
->size());
4551 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
4552 p
!= this->cortex_a8_stubs_
.end();
4555 const Stub_template
* stub_template
= p
->second
->stub_template();
4556 addralign
= std::max(addralign
, stub_template
->alignment());
4557 size
= (align_address(size
, stub_template
->alignment())
4558 + stub_template
->size());
4561 for (Arm_v4bx_stub_list::const_iterator p
= this->arm_v4bx_stubs_
.begin();
4562 p
!= this->arm_v4bx_stubs_
.end();
4568 const Stub_template
* stub_template
= (*p
)->stub_template();
4569 addralign
= std::max(addralign
, stub_template
->alignment());
4570 size
= (align_address(size
, stub_template
->alignment())
4571 + stub_template
->size());
4574 // Check if either data size or alignment changed in this pass.
4575 // Update prev_data_size_ and prev_addralign_. These will be used
4576 // as the current data size and address alignment for the next pass.
4577 bool changed
= size
!= this->prev_data_size_
;
4578 this->prev_data_size_
= size
;
4580 if (addralign
!= this->prev_addralign_
)
4582 this->prev_addralign_
= addralign
;
4587 // Finalize the stubs. This sets the offsets of the stubs within the stub
4588 // table. It also marks all input sections needing Cortex-A8 workaround.
4590 template<bool big_endian
>
4592 Stub_table
<big_endian
>::finalize_stubs()
4595 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
4596 p
!= this->reloc_stubs_
.end();
4599 Reloc_stub
* stub
= p
->second
;
4600 const Stub_template
* stub_template
= stub
->stub_template();
4601 uint64_t stub_addralign
= stub_template
->alignment();
4602 off
= align_address(off
, stub_addralign
);
4603 stub
->set_offset(off
);
4604 off
+= stub_template
->size();
4607 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
4608 p
!= this->cortex_a8_stubs_
.end();
4611 Cortex_a8_stub
* stub
= p
->second
;
4612 const Stub_template
* stub_template
= stub
->stub_template();
4613 uint64_t stub_addralign
= stub_template
->alignment();
4614 off
= align_address(off
, stub_addralign
);
4615 stub
->set_offset(off
);
4616 off
+= stub_template
->size();
4618 // Mark input section so that we can determine later if a code section
4619 // needs the Cortex-A8 workaround quickly.
4620 Arm_relobj
<big_endian
>* arm_relobj
=
4621 Arm_relobj
<big_endian
>::as_arm_relobj(stub
->relobj());
4622 arm_relobj
->mark_section_for_cortex_a8_workaround(stub
->shndx());
4625 for (Arm_v4bx_stub_list::const_iterator p
= this->arm_v4bx_stubs_
.begin();
4626 p
!= this->arm_v4bx_stubs_
.end();
4632 const Stub_template
* stub_template
= (*p
)->stub_template();
4633 uint64_t stub_addralign
= stub_template
->alignment();
4634 off
= align_address(off
, stub_addralign
);
4635 (*p
)->set_offset(off
);
4636 off
+= stub_template
->size();
4639 gold_assert(off
<= this->prev_data_size_
);
4642 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
4643 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
4644 // of the address range seen by the linker.
4646 template<bool big_endian
>
4648 Stub_table
<big_endian
>::apply_cortex_a8_workaround_to_address_range(
4649 Target_arm
<big_endian
>* arm_target
,
4650 unsigned char* view
,
4651 Arm_address view_address
,
4652 section_size_type view_size
)
4654 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
4655 for (Cortex_a8_stub_list::const_iterator p
=
4656 this->cortex_a8_stubs_
.lower_bound(view_address
);
4657 ((p
!= this->cortex_a8_stubs_
.end())
4658 && (p
->first
< (view_address
+ view_size
)));
4661 // We do not store the THUMB bit in the LSB of either the branch address
4662 // or the stub offset. There is no need to strip the LSB.
4663 Arm_address branch_address
= p
->first
;
4664 const Cortex_a8_stub
* stub
= p
->second
;
4665 Arm_address stub_address
= this->address() + stub
->offset();
4667 // Offset of the branch instruction relative to this view.
4668 section_size_type offset
=
4669 convert_to_section_size_type(branch_address
- view_address
);
4670 gold_assert((offset
+ 4) <= view_size
);
4672 arm_target
->apply_cortex_a8_workaround(stub
, stub_address
,
4673 view
+ offset
, branch_address
);
4677 // Arm_input_section methods.
4679 // Initialize an Arm_input_section.
4681 template<bool big_endian
>
4683 Arm_input_section
<big_endian
>::init()
4685 Relobj
* relobj
= this->relobj();
4686 unsigned int shndx
= this->shndx();
4688 // Cache these to speed up size and alignment queries. It is too slow
4689 // to call section_addraglin and section_size every time.
4690 this->original_addralign_
= relobj
->section_addralign(shndx
);
4691 this->original_size_
= relobj
->section_size(shndx
);
4693 // We want to make this look like the original input section after
4694 // output sections are finalized.
4695 Output_section
* os
= relobj
->output_section(shndx
);
4696 off_t offset
= relobj
->output_section_offset(shndx
);
4697 gold_assert(os
!= NULL
&& !relobj
->is_output_section_offset_invalid(shndx
));
4698 this->set_address(os
->address() + offset
);
4699 this->set_file_offset(os
->offset() + offset
);
4701 this->set_current_data_size(this->original_size_
);
4702 this->finalize_data_size();
4705 template<bool big_endian
>
4707 Arm_input_section
<big_endian
>::do_write(Output_file
* of
)
4709 // We have to write out the original section content.
4710 section_size_type section_size
;
4711 const unsigned char* section_contents
=
4712 this->relobj()->section_contents(this->shndx(), §ion_size
, false);
4713 of
->write(this->offset(), section_contents
, section_size
);
4715 // If this owns a stub table and it is not empty, write it.
4716 if (this->is_stub_table_owner() && !this->stub_table_
->empty())
4717 this->stub_table_
->write(of
);
4720 // Finalize data size.
4722 template<bool big_endian
>
4724 Arm_input_section
<big_endian
>::set_final_data_size()
4726 // If this owns a stub table, finalize its data size as well.
4727 if (this->is_stub_table_owner())
4729 uint64_t address
= this->address();
4731 // The stub table comes after the original section contents.
4732 address
+= this->original_size_
;
4733 address
= align_address(address
, this->stub_table_
->addralign());
4734 off_t offset
= this->offset() + (address
- this->address());
4735 this->stub_table_
->set_address_and_file_offset(address
, offset
);
4736 address
+= this->stub_table_
->data_size();
4737 gold_assert(address
== this->address() + this->current_data_size());
4740 this->set_data_size(this->current_data_size());
4743 // Reset address and file offset.
4745 template<bool big_endian
>
4747 Arm_input_section
<big_endian
>::do_reset_address_and_file_offset()
4749 // Size of the original input section contents.
4750 off_t off
= convert_types
<off_t
, uint64_t>(this->original_size_
);
4752 // If this is a stub table owner, account for the stub table size.
4753 if (this->is_stub_table_owner())
4755 Stub_table
<big_endian
>* stub_table
= this->stub_table_
;
4757 // Reset the stub table's address and file offset. The
4758 // current data size for child will be updated after that.
4759 stub_table_
->reset_address_and_file_offset();
4760 off
= align_address(off
, stub_table_
->addralign());
4761 off
+= stub_table
->current_data_size();
4764 this->set_current_data_size(off
);
4767 // Arm_exidx_cantunwind methods.
4769 // Write this to Output file OF for a fixed endianity.
4771 template<bool big_endian
>
4773 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file
* of
)
4775 off_t offset
= this->offset();
4776 const section_size_type oview_size
= 8;
4777 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
4779 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
4780 Valtype
* wv
= reinterpret_cast<Valtype
*>(oview
);
4782 Output_section
* os
= this->relobj_
->output_section(this->shndx_
);
4783 gold_assert(os
!= NULL
);
4785 Arm_relobj
<big_endian
>* arm_relobj
=
4786 Arm_relobj
<big_endian
>::as_arm_relobj(this->relobj_
);
4787 Arm_address output_offset
=
4788 arm_relobj
->get_output_section_offset(this->shndx_
);
4789 Arm_address section_start
;
4790 if(output_offset
!= Arm_relobj
<big_endian
>::invalid_address
)
4791 section_start
= os
->address() + output_offset
;
4794 // Currently this only happens for a relaxed section.
4795 const Output_relaxed_input_section
* poris
=
4796 os
->find_relaxed_input_section(this->relobj_
, this->shndx_
);
4797 gold_assert(poris
!= NULL
);
4798 section_start
= poris
->address();
4801 // We always append this to the end of an EXIDX section.
4802 Arm_address output_address
=
4803 section_start
+ this->relobj_
->section_size(this->shndx_
);
4805 // Write out the entry. The first word either points to the beginning
4806 // or after the end of a text section. The second word is the special
4807 // EXIDX_CANTUNWIND value.
4808 uint32_t prel31_offset
= output_address
- this->address();
4809 if (utils::has_overflow
<31>(offset
))
4810 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
4811 elfcpp::Swap
<32, big_endian
>::writeval(wv
, prel31_offset
& 0x7fffffffU
);
4812 elfcpp::Swap
<32, big_endian
>::writeval(wv
+ 1, elfcpp::EXIDX_CANTUNWIND
);
4814 of
->write_output_view(this->offset(), oview_size
, oview
);
4817 // Arm_exidx_merged_section methods.
4819 // Constructor for Arm_exidx_merged_section.
4820 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
4821 // SECTION_OFFSET_MAP points to a section offset map describing how
4822 // parts of the input section are mapped to output. DELETED_BYTES is
4823 // the number of bytes deleted from the EXIDX input section.
4825 Arm_exidx_merged_section::Arm_exidx_merged_section(
4826 const Arm_exidx_input_section
& exidx_input_section
,
4827 const Arm_exidx_section_offset_map
& section_offset_map
,
4828 uint32_t deleted_bytes
)
4829 : Output_relaxed_input_section(exidx_input_section
.relobj(),
4830 exidx_input_section
.shndx(),
4831 exidx_input_section
.addralign()),
4832 exidx_input_section_(exidx_input_section
),
4833 section_offset_map_(section_offset_map
)
4835 // Fix size here so that we do not need to implement set_final_data_size.
4836 this->set_data_size(exidx_input_section
.size() - deleted_bytes
);
4837 this->fix_data_size();
4840 // Given an input OBJECT, an input section index SHNDX within that
4841 // object, and an OFFSET relative to the start of that input
4842 // section, return whether or not the corresponding offset within
4843 // the output section is known. If this function returns true, it
4844 // sets *POUTPUT to the output offset. The value -1 indicates that
4845 // this input offset is being discarded.
4848 Arm_exidx_merged_section::do_output_offset(
4849 const Relobj
* relobj
,
4851 section_offset_type offset
,
4852 section_offset_type
* poutput
) const
4854 // We only handle offsets for the original EXIDX input section.
4855 if (relobj
!= this->exidx_input_section_
.relobj()
4856 || shndx
!= this->exidx_input_section_
.shndx())
4859 section_offset_type section_size
=
4860 convert_types
<section_offset_type
>(this->exidx_input_section_
.size());
4861 if (offset
< 0 || offset
>= section_size
)
4862 // Input offset is out of valid range.
4866 // We need to look up the section offset map to determine the output
4867 // offset. Find the reference point in map that is first offset
4868 // bigger than or equal to this offset.
4869 Arm_exidx_section_offset_map::const_iterator p
=
4870 this->section_offset_map_
.lower_bound(offset
);
4872 // The section offset maps are build such that this should not happen if
4873 // input offset is in the valid range.
4874 gold_assert(p
!= this->section_offset_map_
.end());
4876 // We need to check if this is dropped.
4877 section_offset_type ref
= p
->first
;
4878 section_offset_type mapped_ref
= p
->second
;
4880 if (mapped_ref
!= Arm_exidx_input_section::invalid_offset
)
4881 // Offset is present in output.
4882 *poutput
= mapped_ref
+ (offset
- ref
);
4884 // Offset is discarded owing to EXIDX entry merging.
4891 // Write this to output file OF.
4894 Arm_exidx_merged_section::do_write(Output_file
* of
)
4896 // If we retain or discard the whole EXIDX input section, we would
4898 gold_assert(this->data_size() != this->exidx_input_section_
.size()
4899 && this->data_size() != 0);
4901 off_t offset
= this->offset();
4902 const section_size_type oview_size
= this->data_size();
4903 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
4905 Output_section
* os
= this->relobj()->output_section(this->shndx());
4906 gold_assert(os
!= NULL
);
4908 // Get contents of EXIDX input section.
4909 section_size_type section_size
;
4910 const unsigned char* section_contents
=
4911 this->relobj()->section_contents(this->shndx(), §ion_size
, false);
4912 gold_assert(section_size
== this->exidx_input_section_
.size());
4914 // Go over spans of input offsets and write only those that are not
4916 section_offset_type in_start
= 0;
4917 section_offset_type out_start
= 0;
4918 for(Arm_exidx_section_offset_map::const_iterator p
=
4919 this->section_offset_map_
.begin();
4920 p
!= this->section_offset_map_
.end();
4923 section_offset_type in_end
= p
->first
;
4924 gold_assert(in_end
>= in_start
);
4925 section_offset_type out_end
= p
->second
;
4926 size_t in_chunk_size
= convert_types
<size_t>(in_end
- in_start
+ 1);
4929 size_t out_chunk_size
=
4930 convert_types
<size_t>(out_end
- out_start
+ 1);
4931 gold_assert(out_chunk_size
== in_chunk_size
);
4932 memcpy(oview
+ out_start
, section_contents
+ in_start
,
4934 out_start
+= out_chunk_size
;
4936 in_start
+= in_chunk_size
;
4939 gold_assert(convert_to_section_size_type(out_start
) == oview_size
);
4940 of
->write_output_view(this->offset(), oview_size
, oview
);
4943 // Arm_exidx_fixup methods.
4945 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
4946 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
4947 // points to the end of the last seen EXIDX section.
4950 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
4952 if (this->last_unwind_type_
!= UT_EXIDX_CANTUNWIND
4953 && this->last_input_section_
!= NULL
)
4955 Relobj
* relobj
= this->last_input_section_
->relobj();
4956 unsigned int text_shndx
= this->last_input_section_
->link();
4957 Arm_exidx_cantunwind
* cantunwind
=
4958 new Arm_exidx_cantunwind(relobj
, text_shndx
);
4959 this->exidx_output_section_
->add_output_section_data(cantunwind
);
4960 this->last_unwind_type_
= UT_EXIDX_CANTUNWIND
;
4964 // Process an EXIDX section entry in input. Return whether this entry
4965 // can be deleted in the output. SECOND_WORD in the second word of the
4969 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word
)
4972 if (second_word
== elfcpp::EXIDX_CANTUNWIND
)
4974 // Merge if previous entry is also an EXIDX_CANTUNWIND.
4975 delete_entry
= this->last_unwind_type_
== UT_EXIDX_CANTUNWIND
;
4976 this->last_unwind_type_
= UT_EXIDX_CANTUNWIND
;
4978 else if ((second_word
& 0x80000000) != 0)
4980 // Inlined unwinding data. Merge if equal to previous.
4981 delete_entry
= (this->last_unwind_type_
== UT_INLINED_ENTRY
4982 && this->last_inlined_entry_
== second_word
);
4983 this->last_unwind_type_
= UT_INLINED_ENTRY
;
4984 this->last_inlined_entry_
= second_word
;
4988 // Normal table entry. In theory we could merge these too,
4989 // but duplicate entries are likely to be much less common.
4990 delete_entry
= false;
4991 this->last_unwind_type_
= UT_NORMAL_ENTRY
;
4993 return delete_entry
;
4996 // Update the current section offset map during EXIDX section fix-up.
4997 // If there is no map, create one. INPUT_OFFSET is the offset of a
4998 // reference point, DELETED_BYTES is the number of deleted by in the
4999 // section so far. If DELETE_ENTRY is true, the reference point and
5000 // all offsets after the previous reference point are discarded.
5003 Arm_exidx_fixup::update_offset_map(
5004 section_offset_type input_offset
,
5005 section_size_type deleted_bytes
,
5008 if (this->section_offset_map_
== NULL
)
5009 this->section_offset_map_
= new Arm_exidx_section_offset_map();
5010 section_offset_type output_offset
= (delete_entry
5012 : input_offset
- deleted_bytes
);
5013 (*this->section_offset_map_
)[input_offset
] = output_offset
;
5016 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5017 // bytes deleted. If some entries are merged, also store a pointer to a newly
5018 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5019 // caller owns the map and is responsible for releasing it after use.
5021 template<bool big_endian
>
5023 Arm_exidx_fixup::process_exidx_section(
5024 const Arm_exidx_input_section
* exidx_input_section
,
5025 Arm_exidx_section_offset_map
** psection_offset_map
)
5027 Relobj
* relobj
= exidx_input_section
->relobj();
5028 unsigned shndx
= exidx_input_section
->shndx();
5029 section_size_type section_size
;
5030 const unsigned char* section_contents
=
5031 relobj
->section_contents(shndx
, §ion_size
, false);
5033 if ((section_size
% 8) != 0)
5035 // Something is wrong with this section. Better not touch it.
5036 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5037 relobj
->name().c_str(), shndx
);
5038 this->last_input_section_
= exidx_input_section
;
5039 this->last_unwind_type_
= UT_NONE
;
5043 uint32_t deleted_bytes
= 0;
5044 bool prev_delete_entry
= false;
5045 gold_assert(this->section_offset_map_
== NULL
);
5047 for (section_size_type i
= 0; i
< section_size
; i
+= 8)
5049 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
5051 reinterpret_cast<const Valtype
*>(section_contents
+ i
+ 4);
5052 uint32_t second_word
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
5054 bool delete_entry
= this->process_exidx_entry(second_word
);
5056 // Entry deletion causes changes in output offsets. We use a std::map
5057 // to record these. And entry (x, y) means input offset x
5058 // is mapped to output offset y. If y is invalid_offset, then x is
5059 // dropped in the output. Because of the way std::map::lower_bound
5060 // works, we record the last offset in a region w.r.t to keeping or
5061 // dropping. If there is no entry (x0, y0) for an input offset x0,
5062 // the output offset y0 of it is determined by the output offset y1 of
5063 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5064 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5066 if (delete_entry
!= prev_delete_entry
&& i
!= 0)
5067 this->update_offset_map(i
- 1, deleted_bytes
, prev_delete_entry
);
5069 // Update total deleted bytes for this entry.
5073 prev_delete_entry
= delete_entry
;
5076 // If section offset map is not NULL, make an entry for the end of
5078 if (this->section_offset_map_
!= NULL
)
5079 update_offset_map(section_size
- 1, deleted_bytes
, prev_delete_entry
);
5081 *psection_offset_map
= this->section_offset_map_
;
5082 this->section_offset_map_
= NULL
;
5083 this->last_input_section_
= exidx_input_section
;
5085 // Set the first output text section so that we can link the EXIDX output
5086 // section to it. Ignore any EXIDX input section that is completely merged.
5087 if (this->first_output_text_section_
== NULL
5088 && deleted_bytes
!= section_size
)
5090 unsigned int link
= exidx_input_section
->link();
5091 Output_section
* os
= relobj
->output_section(link
);
5092 gold_assert(os
!= NULL
);
5093 this->first_output_text_section_
= os
;
5096 return deleted_bytes
;
5099 // Arm_output_section methods.
5101 // Create a stub group for input sections from BEGIN to END. OWNER
5102 // points to the input section to be the owner a new stub table.
5104 template<bool big_endian
>
5106 Arm_output_section
<big_endian
>::create_stub_group(
5107 Input_section_list::const_iterator begin
,
5108 Input_section_list::const_iterator end
,
5109 Input_section_list::const_iterator owner
,
5110 Target_arm
<big_endian
>* target
,
5111 std::vector
<Output_relaxed_input_section
*>* new_relaxed_sections
)
5113 // We use a different kind of relaxed section in an EXIDX section.
5114 // The static casting from Output_relaxed_input_section to
5115 // Arm_input_section is invalid in an EXIDX section. We are okay
5116 // because we should not be calling this for an EXIDX section.
5117 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX
);
5119 // Currently we convert ordinary input sections into relaxed sections only
5120 // at this point but we may want to support creating relaxed input section
5121 // very early. So we check here to see if owner is already a relaxed
5124 Arm_input_section
<big_endian
>* arm_input_section
;
5125 if (owner
->is_relaxed_input_section())
5128 Arm_input_section
<big_endian
>::as_arm_input_section(
5129 owner
->relaxed_input_section());
5133 gold_assert(owner
->is_input_section());
5134 // Create a new relaxed input section.
5136 target
->new_arm_input_section(owner
->relobj(), owner
->shndx());
5137 new_relaxed_sections
->push_back(arm_input_section
);
5140 // Create a stub table.
5141 Stub_table
<big_endian
>* stub_table
=
5142 target
->new_stub_table(arm_input_section
);
5144 arm_input_section
->set_stub_table(stub_table
);
5146 Input_section_list::const_iterator p
= begin
;
5147 Input_section_list::const_iterator prev_p
;
5149 // Look for input sections or relaxed input sections in [begin ... end].
5152 if (p
->is_input_section() || p
->is_relaxed_input_section())
5154 // The stub table information for input sections live
5155 // in their objects.
5156 Arm_relobj
<big_endian
>* arm_relobj
=
5157 Arm_relobj
<big_endian
>::as_arm_relobj(p
->relobj());
5158 arm_relobj
->set_stub_table(p
->shndx(), stub_table
);
5162 while (prev_p
!= end
);
5165 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5166 // of stub groups. We grow a stub group by adding input section until the
5167 // size is just below GROUP_SIZE. The last input section will be converted
5168 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5169 // input section after the stub table, effectively double the group size.
5171 // This is similar to the group_sections() function in elf32-arm.c but is
5172 // implemented differently.
5174 template<bool big_endian
>
5176 Arm_output_section
<big_endian
>::group_sections(
5177 section_size_type group_size
,
5178 bool stubs_always_after_branch
,
5179 Target_arm
<big_endian
>* target
)
5181 // We only care about sections containing code.
5182 if ((this->flags() & elfcpp::SHF_EXECINSTR
) == 0)
5185 // States for grouping.
5188 // No group is being built.
5190 // A group is being built but the stub table is not found yet.
5191 // We keep group a stub group until the size is just under GROUP_SIZE.
5192 // The last input section in the group will be used as the stub table.
5193 FINDING_STUB_SECTION
,
5194 // A group is being built and we have already found a stub table.
5195 // We enter this state to grow a stub group by adding input section
5196 // after the stub table. This effectively doubles the group size.
5200 // Any newly created relaxed sections are stored here.
5201 std::vector
<Output_relaxed_input_section
*> new_relaxed_sections
;
5203 State state
= NO_GROUP
;
5204 section_size_type off
= 0;
5205 section_size_type group_begin_offset
= 0;
5206 section_size_type group_end_offset
= 0;
5207 section_size_type stub_table_end_offset
= 0;
5208 Input_section_list::const_iterator group_begin
=
5209 this->input_sections().end();
5210 Input_section_list::const_iterator stub_table
=
5211 this->input_sections().end();
5212 Input_section_list::const_iterator group_end
= this->input_sections().end();
5213 for (Input_section_list::const_iterator p
= this->input_sections().begin();
5214 p
!= this->input_sections().end();
5217 section_size_type section_begin_offset
=
5218 align_address(off
, p
->addralign());
5219 section_size_type section_end_offset
=
5220 section_begin_offset
+ p
->data_size();
5222 // Check to see if we should group the previously seens sections.
5228 case FINDING_STUB_SECTION
:
5229 // Adding this section makes the group larger than GROUP_SIZE.
5230 if (section_end_offset
- group_begin_offset
>= group_size
)
5232 if (stubs_always_after_branch
)
5234 gold_assert(group_end
!= this->input_sections().end());
5235 this->create_stub_group(group_begin
, group_end
, group_end
,
5236 target
, &new_relaxed_sections
);
5241 // But wait, there's more! Input sections up to
5242 // stub_group_size bytes after the stub table can be
5243 // handled by it too.
5244 state
= HAS_STUB_SECTION
;
5245 stub_table
= group_end
;
5246 stub_table_end_offset
= group_end_offset
;
5251 case HAS_STUB_SECTION
:
5252 // Adding this section makes the post stub-section group larger
5254 if (section_end_offset
- stub_table_end_offset
>= group_size
)
5256 gold_assert(group_end
!= this->input_sections().end());
5257 this->create_stub_group(group_begin
, group_end
, stub_table
,
5258 target
, &new_relaxed_sections
);
5267 // If we see an input section and currently there is no group, start
5268 // a new one. Skip any empty sections.
5269 if ((p
->is_input_section() || p
->is_relaxed_input_section())
5270 && (p
->relobj()->section_size(p
->shndx()) != 0))
5272 if (state
== NO_GROUP
)
5274 state
= FINDING_STUB_SECTION
;
5276 group_begin_offset
= section_begin_offset
;
5279 // Keep track of the last input section seen.
5281 group_end_offset
= section_end_offset
;
5284 off
= section_end_offset
;
5287 // Create a stub group for any ungrouped sections.
5288 if (state
== FINDING_STUB_SECTION
|| state
== HAS_STUB_SECTION
)
5290 gold_assert(group_end
!= this->input_sections().end());
5291 this->create_stub_group(group_begin
, group_end
,
5292 (state
== FINDING_STUB_SECTION
5295 target
, &new_relaxed_sections
);
5298 // Convert input section into relaxed input section in a batch.
5299 if (!new_relaxed_sections
.empty())
5300 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections
);
5302 // Update the section offsets
5303 for (size_t i
= 0; i
< new_relaxed_sections
.size(); ++i
)
5305 Arm_relobj
<big_endian
>* arm_relobj
=
5306 Arm_relobj
<big_endian
>::as_arm_relobj(
5307 new_relaxed_sections
[i
]->relobj());
5308 unsigned int shndx
= new_relaxed_sections
[i
]->shndx();
5309 // Tell Arm_relobj that this input section is converted.
5310 arm_relobj
->convert_input_section_to_relaxed_section(shndx
);
5314 // Append non empty text sections in this to LIST in ascending
5315 // order of their position in this.
5317 template<bool big_endian
>
5319 Arm_output_section
<big_endian
>::append_text_sections_to_list(
5320 Text_section_list
* list
)
5322 // We only care about text sections.
5323 if ((this->flags() & elfcpp::SHF_EXECINSTR
) == 0)
5326 gold_assert((this->flags() & elfcpp::SHF_ALLOC
) != 0);
5328 for (Input_section_list::const_iterator p
= this->input_sections().begin();
5329 p
!= this->input_sections().end();
5332 // We only care about plain or relaxed input sections. We also
5333 // ignore any merged sections.
5334 if ((p
->is_input_section() || p
->is_relaxed_input_section())
5335 && p
->data_size() != 0)
5336 list
->push_back(Text_section_list::value_type(p
->relobj(),
5341 template<bool big_endian
>
5343 Arm_output_section
<big_endian
>::fix_exidx_coverage(
5344 const Text_section_list
& sorted_text_sections
,
5345 Symbol_table
* symtab
)
5347 // We should only do this for the EXIDX output section.
5348 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX
);
5350 // We don't want the relaxation loop to undo these changes, so we discard
5351 // the current saved states and take another one after the fix-up.
5352 this->discard_states();
5354 // Remove all input sections.
5355 uint64_t address
= this->address();
5356 typedef std::list
<Simple_input_section
> Simple_input_section_list
;
5357 Simple_input_section_list input_sections
;
5358 this->reset_address_and_file_offset();
5359 this->get_input_sections(address
, std::string(""), &input_sections
);
5361 if (!this->input_sections().empty())
5362 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5364 // Go through all the known input sections and record them.
5365 typedef Unordered_set
<Section_id
, Section_id_hash
> Section_id_set
;
5366 Section_id_set known_input_sections
;
5367 for (Simple_input_section_list::const_iterator p
= input_sections
.begin();
5368 p
!= input_sections
.end();
5371 // This should never happen. At this point, we should only see
5372 // plain EXIDX input sections.
5373 gold_assert(!p
->is_relaxed_input_section());
5374 known_input_sections
.insert(Section_id(p
->relobj(), p
->shndx()));
5377 Arm_exidx_fixup
exidx_fixup(this);
5379 // Go over the sorted text sections.
5380 Section_id_set processed_input_sections
;
5381 for (Text_section_list::const_iterator p
= sorted_text_sections
.begin();
5382 p
!= sorted_text_sections
.end();
5385 Relobj
* relobj
= p
->first
;
5386 unsigned int shndx
= p
->second
;
5388 Arm_relobj
<big_endian
>* arm_relobj
=
5389 Arm_relobj
<big_endian
>::as_arm_relobj(relobj
);
5390 const Arm_exidx_input_section
* exidx_input_section
=
5391 arm_relobj
->exidx_input_section_by_link(shndx
);
5393 // If this text section has no EXIDX section, force an EXIDX_CANTUNWIND
5394 // entry pointing to the end of the last seen EXIDX section.
5395 if (exidx_input_section
== NULL
)
5397 exidx_fixup
.add_exidx_cantunwind_as_needed();
5401 Relobj
* exidx_relobj
= exidx_input_section
->relobj();
5402 unsigned int exidx_shndx
= exidx_input_section
->shndx();
5403 Section_id
sid(exidx_relobj
, exidx_shndx
);
5404 if (known_input_sections
.find(sid
) == known_input_sections
.end())
5406 // This is odd. We have not seen this EXIDX input section before.
5407 // We cannot do fix-up.
5408 gold_error(_("EXIDX section %u of %s is not in EXIDX output section"),
5409 exidx_shndx
, exidx_relobj
->name().c_str());
5410 exidx_fixup
.add_exidx_cantunwind_as_needed();
5414 // Fix up coverage and append input section to output data list.
5415 Arm_exidx_section_offset_map
* section_offset_map
= NULL
;
5416 uint32_t deleted_bytes
=
5417 exidx_fixup
.process_exidx_section
<big_endian
>(exidx_input_section
,
5418 §ion_offset_map
);
5420 if (deleted_bytes
== exidx_input_section
->size())
5422 // The whole EXIDX section got merged. Remove it from output.
5423 gold_assert(section_offset_map
== NULL
);
5424 exidx_relobj
->set_output_section(exidx_shndx
, NULL
);
5426 // All local symbols defined in this input section will be dropped.
5427 // We need to adjust output local symbol count.
5428 arm_relobj
->set_output_local_symbol_count_needs_update();
5430 else if (deleted_bytes
> 0)
5432 // Some entries are merged. We need to convert this EXIDX input
5433 // section into a relaxed section.
5434 gold_assert(section_offset_map
!= NULL
);
5435 Arm_exidx_merged_section
* merged_section
=
5436 new Arm_exidx_merged_section(*exidx_input_section
,
5437 *section_offset_map
, deleted_bytes
);
5438 this->add_relaxed_input_section(merged_section
);
5439 arm_relobj
->convert_input_section_to_relaxed_section(exidx_shndx
);
5441 // All local symbols defined in discarded portions of this input
5442 // section will be dropped. We need to adjust output local symbol
5444 arm_relobj
->set_output_local_symbol_count_needs_update();
5448 // Just add back the EXIDX input section.
5449 gold_assert(section_offset_map
== NULL
);
5450 Output_section::Simple_input_section
sis(exidx_relobj
, exidx_shndx
);
5451 this->add_simple_input_section(sis
, exidx_input_section
->size(),
5452 exidx_input_section
->addralign());
5455 processed_input_sections
.insert(Section_id(exidx_relobj
, exidx_shndx
));
5458 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5459 exidx_fixup
.add_exidx_cantunwind_as_needed();
5461 // Remove any known EXIDX input sections that are not processed.
5462 for (Simple_input_section_list::const_iterator p
= input_sections
.begin();
5463 p
!= input_sections
.end();
5466 if (processed_input_sections
.find(Section_id(p
->relobj(), p
->shndx()))
5467 == processed_input_sections
.end())
5469 // We only discard a known EXIDX section because its linked
5470 // text section has been folded by ICF.
5471 Arm_relobj
<big_endian
>* arm_relobj
=
5472 Arm_relobj
<big_endian
>::as_arm_relobj(p
->relobj());
5473 const Arm_exidx_input_section
* exidx_input_section
=
5474 arm_relobj
->exidx_input_section_by_shndx(p
->shndx());
5475 gold_assert(exidx_input_section
!= NULL
);
5476 unsigned int text_shndx
= exidx_input_section
->link();
5477 gold_assert(symtab
->is_section_folded(p
->relobj(), text_shndx
));
5479 // Remove this from link.
5480 p
->relobj()->set_output_section(p
->shndx(), NULL
);
5484 // Link exidx output section to the first seen output section and
5485 // set correct entry size.
5486 this->set_link_section(exidx_fixup
.first_output_text_section());
5487 this->set_entsize(8);
5489 // Make changes permanent.
5490 this->save_states();
5491 this->set_section_offsets_need_adjustment();
5494 // Arm_relobj methods.
5496 // Determine if an input section is scannable for stub processing. SHDR is
5497 // the header of the section and SHNDX is the section index. OS is the output
5498 // section for the input section and SYMTAB is the global symbol table used to
5499 // look up ICF information.
5501 template<bool big_endian
>
5503 Arm_relobj
<big_endian
>::section_is_scannable(
5504 const elfcpp::Shdr
<32, big_endian
>& shdr
,
5506 const Output_section
* os
,
5507 const Symbol_table
*symtab
)
5509 // Skip any empty sections, unallocated sections or sections whose
5510 // type are not SHT_PROGBITS.
5511 if (shdr
.get_sh_size() == 0
5512 || (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0
5513 || shdr
.get_sh_type() != elfcpp::SHT_PROGBITS
)
5516 // Skip any discarded or ICF'ed sections.
5517 if (os
== NULL
|| symtab
->is_section_folded(this, shndx
))
5520 // If this requires special offset handling, check to see if it is
5521 // a relaxed section. If this is not, then it is a merged section that
5522 // we cannot handle.
5523 if (this->is_output_section_offset_invalid(shndx
))
5525 const Output_relaxed_input_section
* poris
=
5526 os
->find_relaxed_input_section(this, shndx
);
5534 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5535 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5537 template<bool big_endian
>
5539 Arm_relobj
<big_endian
>::section_needs_reloc_stub_scanning(
5540 const elfcpp::Shdr
<32, big_endian
>& shdr
,
5541 const Relobj::Output_sections
& out_sections
,
5542 const Symbol_table
*symtab
,
5543 const unsigned char* pshdrs
)
5545 unsigned int sh_type
= shdr
.get_sh_type();
5546 if (sh_type
!= elfcpp::SHT_REL
&& sh_type
!= elfcpp::SHT_RELA
)
5549 // Ignore empty section.
5550 off_t sh_size
= shdr
.get_sh_size();
5554 // Ignore reloc section with unexpected symbol table. The
5555 // error will be reported in the final link.
5556 if (this->adjust_shndx(shdr
.get_sh_link()) != this->symtab_shndx())
5559 unsigned int reloc_size
;
5560 if (sh_type
== elfcpp::SHT_REL
)
5561 reloc_size
= elfcpp::Elf_sizes
<32>::rel_size
;
5563 reloc_size
= elfcpp::Elf_sizes
<32>::rela_size
;
5565 // Ignore reloc section with unexpected entsize or uneven size.
5566 // The error will be reported in the final link.
5567 if (reloc_size
!= shdr
.get_sh_entsize() || sh_size
% reloc_size
!= 0)
5570 // Ignore reloc section with bad info. This error will be
5571 // reported in the final link.
5572 unsigned int index
= this->adjust_shndx(shdr
.get_sh_info());
5573 if (index
>= this->shnum())
5576 const unsigned int shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
5577 const elfcpp::Shdr
<32, big_endian
> text_shdr(pshdrs
+ index
* shdr_size
);
5578 return this->section_is_scannable(text_shdr
, index
,
5579 out_sections
[index
], symtab
);
5582 // Return the output address of either a plain input section or a relaxed
5583 // input section. SHNDX is the section index. We define and use this
5584 // instead of calling Output_section::output_address because that is slow
5585 // for large output.
5587 template<bool big_endian
>
5589 Arm_relobj
<big_endian
>::simple_input_section_output_address(
5593 if (this->is_output_section_offset_invalid(shndx
))
5595 const Output_relaxed_input_section
* poris
=
5596 os
->find_relaxed_input_section(this, shndx
);
5597 // We do not handle merged sections here.
5598 gold_assert(poris
!= NULL
);
5599 return poris
->address();
5602 return os
->address() + this->get_output_section_offset(shndx
);
5605 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
5606 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5608 template<bool big_endian
>
5610 Arm_relobj
<big_endian
>::section_needs_cortex_a8_stub_scanning(
5611 const elfcpp::Shdr
<32, big_endian
>& shdr
,
5614 const Symbol_table
* symtab
)
5616 if (!this->section_is_scannable(shdr
, shndx
, os
, symtab
))
5619 // If the section does not cross any 4K-boundaries, it does not need to
5621 Arm_address address
= this->simple_input_section_output_address(shndx
, os
);
5622 if ((address
& ~0xfffU
) == ((address
+ shdr
.get_sh_size() - 1) & ~0xfffU
))
5628 // Scan a section for Cortex-A8 workaround.
5630 template<bool big_endian
>
5632 Arm_relobj
<big_endian
>::scan_section_for_cortex_a8_erratum(
5633 const elfcpp::Shdr
<32, big_endian
>& shdr
,
5636 Target_arm
<big_endian
>* arm_target
)
5638 // Look for the first mapping symbol in this section. It should be
5640 Mapping_symbol_position
section_start(shndx
, 0);
5641 typename
Mapping_symbols_info::const_iterator p
=
5642 this->mapping_symbols_info_
.lower_bound(section_start
);
5644 // There are no mapping symbols for this section. Treat it as a data-only
5646 if (p
== this->mapping_symbols_info_
.end() || p
->first
.first
!= shndx
)
5649 Arm_address output_address
=
5650 this->simple_input_section_output_address(shndx
, os
);
5652 // Get the section contents.
5653 section_size_type input_view_size
= 0;
5654 const unsigned char* input_view
=
5655 this->section_contents(shndx
, &input_view_size
, false);
5657 // We need to go through the mapping symbols to determine what to
5658 // scan. There are two reasons. First, we should look at THUMB code and
5659 // THUMB code only. Second, we only want to look at the 4K-page boundary
5660 // to speed up the scanning.
5662 while (p
!= this->mapping_symbols_info_
.end()
5663 && p
->first
.first
== shndx
)
5665 typename
Mapping_symbols_info::const_iterator next
=
5666 this->mapping_symbols_info_
.upper_bound(p
->first
);
5668 // Only scan part of a section with THUMB code.
5669 if (p
->second
== 't')
5671 // Determine the end of this range.
5672 section_size_type span_start
=
5673 convert_to_section_size_type(p
->first
.second
);
5674 section_size_type span_end
;
5675 if (next
!= this->mapping_symbols_info_
.end()
5676 && next
->first
.first
== shndx
)
5677 span_end
= convert_to_section_size_type(next
->first
.second
);
5679 span_end
= convert_to_section_size_type(shdr
.get_sh_size());
5681 if (((span_start
+ output_address
) & ~0xfffUL
)
5682 != ((span_end
+ output_address
- 1) & ~0xfffUL
))
5684 arm_target
->scan_span_for_cortex_a8_erratum(this, shndx
,
5685 span_start
, span_end
,
5695 // Scan relocations for stub generation.
5697 template<bool big_endian
>
5699 Arm_relobj
<big_endian
>::scan_sections_for_stubs(
5700 Target_arm
<big_endian
>* arm_target
,
5701 const Symbol_table
* symtab
,
5702 const Layout
* layout
)
5704 unsigned int shnum
= this->shnum();
5705 const unsigned int shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
5707 // Read the section headers.
5708 const unsigned char* pshdrs
= this->get_view(this->elf_file()->shoff(),
5712 // To speed up processing, we set up hash tables for fast lookup of
5713 // input offsets to output addresses.
5714 this->initialize_input_to_output_maps();
5716 const Relobj::Output_sections
& out_sections(this->output_sections());
5718 Relocate_info
<32, big_endian
> relinfo
;
5719 relinfo
.symtab
= symtab
;
5720 relinfo
.layout
= layout
;
5721 relinfo
.object
= this;
5723 // Do relocation stubs scanning.
5724 const unsigned char* p
= pshdrs
+ shdr_size
;
5725 for (unsigned int i
= 1; i
< shnum
; ++i
, p
+= shdr_size
)
5727 const elfcpp::Shdr
<32, big_endian
> shdr(p
);
5728 if (this->section_needs_reloc_stub_scanning(shdr
, out_sections
, symtab
,
5731 unsigned int index
= this->adjust_shndx(shdr
.get_sh_info());
5732 Arm_address output_offset
= this->get_output_section_offset(index
);
5733 Arm_address output_address
;
5734 if(output_offset
!= invalid_address
)
5735 output_address
= out_sections
[index
]->address() + output_offset
;
5738 // Currently this only happens for a relaxed section.
5739 const Output_relaxed_input_section
* poris
=
5740 out_sections
[index
]->find_relaxed_input_section(this, index
);
5741 gold_assert(poris
!= NULL
);
5742 output_address
= poris
->address();
5745 // Get the relocations.
5746 const unsigned char* prelocs
= this->get_view(shdr
.get_sh_offset(),
5750 // Get the section contents. This does work for the case in which
5751 // we modify the contents of an input section. We need to pass the
5752 // output view under such circumstances.
5753 section_size_type input_view_size
= 0;
5754 const unsigned char* input_view
=
5755 this->section_contents(index
, &input_view_size
, false);
5757 relinfo
.reloc_shndx
= i
;
5758 relinfo
.data_shndx
= index
;
5759 unsigned int sh_type
= shdr
.get_sh_type();
5760 unsigned int reloc_size
;
5761 if (sh_type
== elfcpp::SHT_REL
)
5762 reloc_size
= elfcpp::Elf_sizes
<32>::rel_size
;
5764 reloc_size
= elfcpp::Elf_sizes
<32>::rela_size
;
5766 Output_section
* os
= out_sections
[index
];
5767 arm_target
->scan_section_for_stubs(&relinfo
, sh_type
, prelocs
,
5768 shdr
.get_sh_size() / reloc_size
,
5770 output_offset
== invalid_address
,
5771 input_view
, output_address
,
5776 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
5777 // after its relocation section, if there is one, is processed for
5778 // relocation stubs. Merging this loop with the one above would have been
5779 // complicated since we would have had to make sure that relocation stub
5780 // scanning is done first.
5781 if (arm_target
->fix_cortex_a8())
5783 const unsigned char* p
= pshdrs
+ shdr_size
;
5784 for (unsigned int i
= 1; i
< shnum
; ++i
, p
+= shdr_size
)
5786 const elfcpp::Shdr
<32, big_endian
> shdr(p
);
5787 if (this->section_needs_cortex_a8_stub_scanning(shdr
, i
,
5790 this->scan_section_for_cortex_a8_erratum(shdr
, i
, out_sections
[i
],
5795 // After we've done the relocations, we release the hash tables,
5796 // since we no longer need them.
5797 this->free_input_to_output_maps();
5800 // Count the local symbols. The ARM backend needs to know if a symbol
5801 // is a THUMB function or not. For global symbols, it is easy because
5802 // the Symbol object keeps the ELF symbol type. For local symbol it is
5803 // harder because we cannot access this information. So we override the
5804 // do_count_local_symbol in parent and scan local symbols to mark
5805 // THUMB functions. This is not the most efficient way but I do not want to
5806 // slow down other ports by calling a per symbol targer hook inside
5807 // Sized_relobj<size, big_endian>::do_count_local_symbols.
5809 template<bool big_endian
>
5811 Arm_relobj
<big_endian
>::do_count_local_symbols(
5812 Stringpool_template
<char>* pool
,
5813 Stringpool_template
<char>* dynpool
)
5815 // We need to fix-up the values of any local symbols whose type are
5818 // Ask parent to count the local symbols.
5819 Sized_relobj
<32, big_endian
>::do_count_local_symbols(pool
, dynpool
);
5820 const unsigned int loccount
= this->local_symbol_count();
5824 // Intialize the thumb function bit-vector.
5825 std::vector
<bool> empty_vector(loccount
, false);
5826 this->local_symbol_is_thumb_function_
.swap(empty_vector
);
5828 // Read the symbol table section header.
5829 const unsigned int symtab_shndx
= this->symtab_shndx();
5830 elfcpp::Shdr
<32, big_endian
>
5831 symtabshdr(this, this->elf_file()->section_header(symtab_shndx
));
5832 gold_assert(symtabshdr
.get_sh_type() == elfcpp::SHT_SYMTAB
);
5834 // Read the local symbols.
5835 const int sym_size
=elfcpp::Elf_sizes
<32>::sym_size
;
5836 gold_assert(loccount
== symtabshdr
.get_sh_info());
5837 off_t locsize
= loccount
* sym_size
;
5838 const unsigned char* psyms
= this->get_view(symtabshdr
.get_sh_offset(),
5839 locsize
, true, true);
5841 // For mapping symbol processing, we need to read the symbol names.
5842 unsigned int strtab_shndx
= this->adjust_shndx(symtabshdr
.get_sh_link());
5843 if (strtab_shndx
>= this->shnum())
5845 this->error(_("invalid symbol table name index: %u"), strtab_shndx
);
5849 elfcpp::Shdr
<32, big_endian
>
5850 strtabshdr(this, this->elf_file()->section_header(strtab_shndx
));
5851 if (strtabshdr
.get_sh_type() != elfcpp::SHT_STRTAB
)
5853 this->error(_("symbol table name section has wrong type: %u"),
5854 static_cast<unsigned int>(strtabshdr
.get_sh_type()));
5857 const char* pnames
=
5858 reinterpret_cast<const char*>(this->get_view(strtabshdr
.get_sh_offset(),
5859 strtabshdr
.get_sh_size(),
5862 // Loop over the local symbols and mark any local symbols pointing
5863 // to THUMB functions.
5865 // Skip the first dummy symbol.
5867 typename Sized_relobj
<32, big_endian
>::Local_values
* plocal_values
=
5868 this->local_values();
5869 for (unsigned int i
= 1; i
< loccount
; ++i
, psyms
+= sym_size
)
5871 elfcpp::Sym
<32, big_endian
> sym(psyms
);
5872 elfcpp::STT st_type
= sym
.get_st_type();
5873 Symbol_value
<32>& lv((*plocal_values
)[i
]);
5874 Arm_address input_value
= lv
.input_value();
5876 // Check to see if this is a mapping symbol.
5877 const char* sym_name
= pnames
+ sym
.get_st_name();
5878 if (Target_arm
<big_endian
>::is_mapping_symbol_name(sym_name
))
5880 unsigned int input_shndx
= sym
.get_st_shndx();
5882 // Strip of LSB in case this is a THUMB symbol.
5883 Mapping_symbol_position
msp(input_shndx
, input_value
& ~1U);
5884 this->mapping_symbols_info_
[msp
] = sym_name
[1];
5887 if (st_type
== elfcpp::STT_ARM_TFUNC
5888 || (st_type
== elfcpp::STT_FUNC
&& ((input_value
& 1) != 0)))
5890 // This is a THUMB function. Mark this and canonicalize the
5891 // symbol value by setting LSB.
5892 this->local_symbol_is_thumb_function_
[i
] = true;
5893 if ((input_value
& 1) == 0)
5894 lv
.set_input_value(input_value
| 1);
5899 // Relocate sections.
5900 template<bool big_endian
>
5902 Arm_relobj
<big_endian
>::do_relocate_sections(
5903 const Symbol_table
* symtab
,
5904 const Layout
* layout
,
5905 const unsigned char* pshdrs
,
5906 typename Sized_relobj
<32, big_endian
>::Views
* pviews
)
5908 // Call parent to relocate sections.
5909 Sized_relobj
<32, big_endian
>::do_relocate_sections(symtab
, layout
, pshdrs
,
5912 // We do not generate stubs if doing a relocatable link.
5913 if (parameters
->options().relocatable())
5916 // Relocate stub tables.
5917 unsigned int shnum
= this->shnum();
5919 Target_arm
<big_endian
>* arm_target
=
5920 Target_arm
<big_endian
>::default_target();
5922 Relocate_info
<32, big_endian
> relinfo
;
5923 relinfo
.symtab
= symtab
;
5924 relinfo
.layout
= layout
;
5925 relinfo
.object
= this;
5927 for (unsigned int i
= 1; i
< shnum
; ++i
)
5929 Arm_input_section
<big_endian
>* arm_input_section
=
5930 arm_target
->find_arm_input_section(this, i
);
5932 if (arm_input_section
!= NULL
5933 && arm_input_section
->is_stub_table_owner()
5934 && !arm_input_section
->stub_table()->empty())
5936 // We cannot discard a section if it owns a stub table.
5937 Output_section
* os
= this->output_section(i
);
5938 gold_assert(os
!= NULL
);
5940 relinfo
.reloc_shndx
= elfcpp::SHN_UNDEF
;
5941 relinfo
.reloc_shdr
= NULL
;
5942 relinfo
.data_shndx
= i
;
5943 relinfo
.data_shdr
= pshdrs
+ i
* elfcpp::Elf_sizes
<32>::shdr_size
;
5945 gold_assert((*pviews
)[i
].view
!= NULL
);
5947 // We are passed the output section view. Adjust it to cover the
5949 Stub_table
<big_endian
>* stub_table
= arm_input_section
->stub_table();
5950 gold_assert((stub_table
->address() >= (*pviews
)[i
].address
)
5951 && ((stub_table
->address() + stub_table
->data_size())
5952 <= (*pviews
)[i
].address
+ (*pviews
)[i
].view_size
));
5954 off_t offset
= stub_table
->address() - (*pviews
)[i
].address
;
5955 unsigned char* view
= (*pviews
)[i
].view
+ offset
;
5956 Arm_address address
= stub_table
->address();
5957 section_size_type view_size
= stub_table
->data_size();
5959 stub_table
->relocate_stubs(&relinfo
, arm_target
, os
, view
, address
,
5963 // Apply Cortex A8 workaround if applicable.
5964 if (this->section_has_cortex_a8_workaround(i
))
5966 unsigned char* view
= (*pviews
)[i
].view
;
5967 Arm_address view_address
= (*pviews
)[i
].address
;
5968 section_size_type view_size
= (*pviews
)[i
].view_size
;
5969 Stub_table
<big_endian
>* stub_table
= this->stub_tables_
[i
];
5971 // Adjust view to cover section.
5972 Output_section
* os
= this->output_section(i
);
5973 gold_assert(os
!= NULL
);
5974 Arm_address section_address
=
5975 this->simple_input_section_output_address(i
, os
);
5976 uint64_t section_size
= this->section_size(i
);
5978 gold_assert(section_address
>= view_address
5979 && ((section_address
+ section_size
)
5980 <= (view_address
+ view_size
)));
5982 unsigned char* section_view
= view
+ (section_address
- view_address
);
5984 // Apply the Cortex-A8 workaround to the output address range
5985 // corresponding to this input section.
5986 stub_table
->apply_cortex_a8_workaround_to_address_range(
5995 // Find the linked text section of an EXIDX section by looking the the first
5996 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
5997 // must be linked to to its associated code section via the sh_link field of
5998 // its section header. However, some tools are broken and the link is not
5999 // always set. LD just drops such an EXIDX section silently, causing the
6000 // associated code not unwindabled. Here we try a little bit harder to
6001 // discover the linked code section.
6003 // PSHDR points to the section header of a relocation section of an EXIDX
6004 // section. If we can find a linked text section, return true and
6005 // store the text section index in the location PSHNDX. Otherwise
6008 template<bool big_endian
>
6010 Arm_relobj
<big_endian
>::find_linked_text_section(
6011 const unsigned char* pshdr
,
6012 const unsigned char* psyms
,
6013 unsigned int* pshndx
)
6015 elfcpp::Shdr
<32, big_endian
> shdr(pshdr
);
6017 // If there is no relocation, we cannot find the linked text section.
6019 if (shdr
.get_sh_type() == elfcpp::SHT_REL
)
6020 reloc_size
= elfcpp::Elf_sizes
<32>::rel_size
;
6022 reloc_size
= elfcpp::Elf_sizes
<32>::rela_size
;
6023 size_t reloc_count
= shdr
.get_sh_size() / reloc_size
;
6025 // Get the relocations.
6026 const unsigned char* prelocs
=
6027 this->get_view(shdr
.get_sh_offset(), shdr
.get_sh_size(), true, false);
6029 // Find the REL31 relocation for the first word of the first EXIDX entry.
6030 for (size_t i
= 0; i
< reloc_count
; ++i
, prelocs
+= reloc_size
)
6032 Arm_address r_offset
;
6033 typename
elfcpp::Elf_types
<32>::Elf_WXword r_info
;
6034 if (shdr
.get_sh_type() == elfcpp::SHT_REL
)
6036 typename
elfcpp::Rel
<32, big_endian
> reloc(prelocs
);
6037 r_info
= reloc
.get_r_info();
6038 r_offset
= reloc
.get_r_offset();
6042 typename
elfcpp::Rela
<32, big_endian
> reloc(prelocs
);
6043 r_info
= reloc
.get_r_info();
6044 r_offset
= reloc
.get_r_offset();
6047 unsigned int r_type
= elfcpp::elf_r_type
<32>(r_info
);
6048 if (r_type
!= elfcpp::R_ARM_PREL31
&& r_type
!= elfcpp::R_ARM_SBREL31
)
6051 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(r_info
);
6053 || r_sym
>= this->local_symbol_count()
6057 // This is the relocation for the first word of the first EXIDX entry.
6058 // We expect to see a local section symbol.
6059 const int sym_size
= elfcpp::Elf_sizes
<32>::sym_size
;
6060 elfcpp::Sym
<32, big_endian
> sym(psyms
+ r_sym
* sym_size
);
6061 if (sym
.get_st_type() == elfcpp::STT_SECTION
)
6063 *pshndx
= this->adjust_shndx(sym
.get_st_shndx());
6073 // Make an EXIDX input section object for an EXIDX section whose index is
6074 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6075 // is the section index of the linked text section.
6077 template<bool big_endian
>
6079 Arm_relobj
<big_endian
>::make_exidx_input_section(
6081 const elfcpp::Shdr
<32, big_endian
>& shdr
,
6082 unsigned int text_shndx
)
6084 // Issue an error and ignore this EXIDX section if it points to a text
6085 // section already has an EXIDX section.
6086 if (this->exidx_section_map_
[text_shndx
] != NULL
)
6088 gold_error(_("EXIDX sections %u and %u both link to text section %u "
6090 shndx
, this->exidx_section_map_
[text_shndx
]->shndx(),
6091 text_shndx
, this->name().c_str());
6095 // Create an Arm_exidx_input_section object for this EXIDX section.
6096 Arm_exidx_input_section
* exidx_input_section
=
6097 new Arm_exidx_input_section(this, shndx
, text_shndx
, shdr
.get_sh_size(),
6098 shdr
.get_sh_addralign());
6099 this->exidx_section_map_
[text_shndx
] = exidx_input_section
;
6101 // Also map the EXIDX section index to this.
6102 gold_assert(this->exidx_section_map_
[shndx
] == NULL
);
6103 this->exidx_section_map_
[shndx
] = exidx_input_section
;
6106 // Read the symbol information.
6108 template<bool big_endian
>
6110 Arm_relobj
<big_endian
>::do_read_symbols(Read_symbols_data
* sd
)
6112 // Call parent class to read symbol information.
6113 Sized_relobj
<32, big_endian
>::do_read_symbols(sd
);
6115 // Read processor-specific flags in ELF file header.
6116 const unsigned char* pehdr
= this->get_view(elfcpp::file_header_offset
,
6117 elfcpp::Elf_sizes
<32>::ehdr_size
,
6119 elfcpp::Ehdr
<32, big_endian
> ehdr(pehdr
);
6120 this->processor_specific_flags_
= ehdr
.get_e_flags();
6122 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6124 std::vector
<unsigned int> deferred_exidx_sections
;
6125 const size_t shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
6126 const unsigned char* pshdrs
= sd
->section_headers
->data();
6127 const unsigned char *ps
= pshdrs
+ shdr_size
;
6128 for (unsigned int i
= 1; i
< this->shnum(); ++i
, ps
+= shdr_size
)
6130 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
6131 if (shdr
.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES
)
6133 gold_assert(this->attributes_section_data_
== NULL
);
6134 section_offset_type section_offset
= shdr
.get_sh_offset();
6135 section_size_type section_size
=
6136 convert_to_section_size_type(shdr
.get_sh_size());
6137 File_view
* view
= this->get_lasting_view(section_offset
,
6138 section_size
, true, false);
6139 this->attributes_section_data_
=
6140 new Attributes_section_data(view
->data(), section_size
);
6142 else if (shdr
.get_sh_type() == elfcpp::SHT_ARM_EXIDX
)
6144 unsigned int text_shndx
= this->adjust_shndx(shdr
.get_sh_link());
6145 if (text_shndx
>= this->shnum())
6146 gold_error(_("EXIDX section %u linked to invalid section %u"),
6148 else if (text_shndx
== elfcpp::SHN_UNDEF
)
6149 deferred_exidx_sections
.push_back(i
);
6151 this->make_exidx_input_section(i
, shdr
, text_shndx
);
6155 // Some tools are broken and they do not set the link of EXIDX sections.
6156 // We look at the first relocation to figure out the linked sections.
6157 if (!deferred_exidx_sections
.empty())
6159 // We need to go over the section headers again to find the mapping
6160 // from sections being relocated to their relocation sections. This is
6161 // a bit inefficient as we could do that in the loop above. However,
6162 // we do not expect any deferred EXIDX sections normally. So we do not
6163 // want to slow down the most common path.
6164 typedef Unordered_map
<unsigned int, unsigned int> Reloc_map
;
6165 Reloc_map reloc_map
;
6166 ps
= pshdrs
+ shdr_size
;
6167 for (unsigned int i
= 1; i
< this->shnum(); ++i
, ps
+= shdr_size
)
6169 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
6170 elfcpp::Elf_Word sh_type
= shdr
.get_sh_type();
6171 if (sh_type
== elfcpp::SHT_REL
|| sh_type
== elfcpp::SHT_RELA
)
6173 unsigned int info_shndx
= this->adjust_shndx(shdr
.get_sh_info());
6174 if (info_shndx
>= this->shnum())
6175 gold_error(_("relocation section %u has invalid info %u"),
6177 Reloc_map::value_type
value(info_shndx
, i
);
6178 std::pair
<Reloc_map::iterator
, bool> result
=
6179 reloc_map
.insert(value
);
6181 gold_error(_("section %u has multiple relocation sections "
6183 info_shndx
, i
, reloc_map
[info_shndx
]);
6187 // Read the symbol table section header.
6188 const unsigned int symtab_shndx
= this->symtab_shndx();
6189 elfcpp::Shdr
<32, big_endian
>
6190 symtabshdr(this, this->elf_file()->section_header(symtab_shndx
));
6191 gold_assert(symtabshdr
.get_sh_type() == elfcpp::SHT_SYMTAB
);
6193 // Read the local symbols.
6194 const int sym_size
=elfcpp::Elf_sizes
<32>::sym_size
;
6195 const unsigned int loccount
= this->local_symbol_count();
6196 gold_assert(loccount
== symtabshdr
.get_sh_info());
6197 off_t locsize
= loccount
* sym_size
;
6198 const unsigned char* psyms
= this->get_view(symtabshdr
.get_sh_offset(),
6199 locsize
, true, true);
6201 // Process the deferred EXIDX sections.
6202 for(unsigned int i
= 0; i
< deferred_exidx_sections
.size(); ++i
)
6204 unsigned int shndx
= deferred_exidx_sections
[i
];
6205 elfcpp::Shdr
<32, big_endian
> shdr(pshdrs
+ shndx
* shdr_size
);
6206 unsigned int text_shndx
;
6207 Reloc_map::const_iterator it
= reloc_map
.find(shndx
);
6208 if (it
!= reloc_map
.end()
6209 && find_linked_text_section(pshdrs
+ it
->second
* shdr_size
,
6210 psyms
, &text_shndx
))
6211 this->make_exidx_input_section(shndx
, shdr
, text_shndx
);
6213 gold_error(_("EXIDX section %u has no linked text section."),
6219 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6220 // sections for unwinding. These sections are referenced implicitly by
6221 // text sections linked in the section headers. If we ignore these implict
6222 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6223 // will be garbage-collected incorrectly. Hence we override the same function
6224 // in the base class to handle these implicit references.
6226 template<bool big_endian
>
6228 Arm_relobj
<big_endian
>::do_gc_process_relocs(Symbol_table
* symtab
,
6230 Read_relocs_data
* rd
)
6232 // First, call base class method to process relocations in this object.
6233 Sized_relobj
<32, big_endian
>::do_gc_process_relocs(symtab
, layout
, rd
);
6235 unsigned int shnum
= this->shnum();
6236 const unsigned int shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
6237 const unsigned char* pshdrs
= this->get_view(this->elf_file()->shoff(),
6241 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6242 // to these from the linked text sections.
6243 const unsigned char* ps
= pshdrs
+ shdr_size
;
6244 for (unsigned int i
= 1; i
< shnum
; ++i
, ps
+= shdr_size
)
6246 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
6247 if (shdr
.get_sh_type() == elfcpp::SHT_ARM_EXIDX
)
6249 // Found an .ARM.exidx section, add it to the set of reachable
6250 // sections from its linked text section.
6251 unsigned int text_shndx
= this->adjust_shndx(shdr
.get_sh_link());
6252 symtab
->gc()->add_reference(this, text_shndx
, this, i
);
6257 // Update output local symbol count. Owing to EXIDX entry merging, some local
6258 // symbols will be removed in output. Adjust output local symbol count
6259 // accordingly. We can only changed the static output local symbol count. It
6260 // is too late to change the dynamic symbols.
6262 template<bool big_endian
>
6264 Arm_relobj
<big_endian
>::update_output_local_symbol_count()
6266 // Caller should check that this needs updating. We want caller checking
6267 // because output_local_symbol_count_needs_update() is most likely inlined.
6268 gold_assert(this->output_local_symbol_count_needs_update_
);
6270 gold_assert(this->symtab_shndx() != -1U);
6271 if (this->symtab_shndx() == 0)
6273 // This object has no symbols. Weird but legal.
6277 // Read the symbol table section header.
6278 const unsigned int symtab_shndx
= this->symtab_shndx();
6279 elfcpp::Shdr
<32, big_endian
>
6280 symtabshdr(this, this->elf_file()->section_header(symtab_shndx
));
6281 gold_assert(symtabshdr
.get_sh_type() == elfcpp::SHT_SYMTAB
);
6283 // Read the local symbols.
6284 const int sym_size
= elfcpp::Elf_sizes
<32>::sym_size
;
6285 const unsigned int loccount
= this->local_symbol_count();
6286 gold_assert(loccount
== symtabshdr
.get_sh_info());
6287 off_t locsize
= loccount
* sym_size
;
6288 const unsigned char* psyms
= this->get_view(symtabshdr
.get_sh_offset(),
6289 locsize
, true, true);
6291 // Loop over the local symbols.
6293 typedef typename Sized_relobj
<32, big_endian
>::Output_sections
6295 const Output_sections
& out_sections(this->output_sections());
6296 unsigned int shnum
= this->shnum();
6297 unsigned int count
= 0;
6298 // Skip the first, dummy, symbol.
6300 for (unsigned int i
= 1; i
< loccount
; ++i
, psyms
+= sym_size
)
6302 elfcpp::Sym
<32, big_endian
> sym(psyms
);
6304 Symbol_value
<32>& lv((*this->local_values())[i
]);
6306 // This local symbol was already discarded by do_count_local_symbols.
6307 if (!lv
.needs_output_symtab_entry())
6311 unsigned int shndx
= this->adjust_sym_shndx(i
, sym
.get_st_shndx(),
6316 Output_section
* os
= out_sections
[shndx
];
6318 // This local symbol no longer has an output section. Discard it.
6321 lv
.set_no_output_symtab_entry();
6325 // Currently we only discard parts of EXIDX input sections.
6326 // We explicitly check for a merged EXIDX input section to avoid
6327 // calling Output_section_data::output_offset unless necessary.
6328 if ((this->get_output_section_offset(shndx
) == invalid_address
)
6329 && (this->exidx_input_section_by_shndx(shndx
) != NULL
))
6331 section_offset_type output_offset
=
6332 os
->output_offset(this, shndx
, lv
.input_value());
6333 if (output_offset
== -1)
6335 // This symbol is defined in a part of an EXIDX input section
6336 // that is discarded due to entry merging.
6337 lv
.set_no_output_symtab_entry();
6346 this->set_output_local_symbol_count(count
);
6347 this->output_local_symbol_count_needs_update_
= false;
6350 // Arm_dynobj methods.
6352 // Read the symbol information.
6354 template<bool big_endian
>
6356 Arm_dynobj
<big_endian
>::do_read_symbols(Read_symbols_data
* sd
)
6358 // Call parent class to read symbol information.
6359 Sized_dynobj
<32, big_endian
>::do_read_symbols(sd
);
6361 // Read processor-specific flags in ELF file header.
6362 const unsigned char* pehdr
= this->get_view(elfcpp::file_header_offset
,
6363 elfcpp::Elf_sizes
<32>::ehdr_size
,
6365 elfcpp::Ehdr
<32, big_endian
> ehdr(pehdr
);
6366 this->processor_specific_flags_
= ehdr
.get_e_flags();
6368 // Read the attributes section if there is one.
6369 // We read from the end because gas seems to put it near the end of
6370 // the section headers.
6371 const size_t shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
6372 const unsigned char *ps
=
6373 sd
->section_headers
->data() + shdr_size
* (this->shnum() - 1);
6374 for (unsigned int i
= this->shnum(); i
> 0; --i
, ps
-= shdr_size
)
6376 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
6377 if (shdr
.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES
)
6379 section_offset_type section_offset
= shdr
.get_sh_offset();
6380 section_size_type section_size
=
6381 convert_to_section_size_type(shdr
.get_sh_size());
6382 File_view
* view
= this->get_lasting_view(section_offset
,
6383 section_size
, true, false);
6384 this->attributes_section_data_
=
6385 new Attributes_section_data(view
->data(), section_size
);
6391 // Stub_addend_reader methods.
6393 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6395 template<bool big_endian
>
6396 elfcpp::Elf_types
<32>::Elf_Swxword
6397 Stub_addend_reader
<elfcpp::SHT_REL
, big_endian
>::operator()(
6398 unsigned int r_type
,
6399 const unsigned char* view
,
6400 const typename Reloc_types
<elfcpp::SHT_REL
, 32, big_endian
>::Reloc
&) const
6402 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
6406 case elfcpp::R_ARM_CALL
:
6407 case elfcpp::R_ARM_JUMP24
:
6408 case elfcpp::R_ARM_PLT32
:
6410 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
6411 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
6412 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
6413 return utils::sign_extend
<26>(val
<< 2);
6416 case elfcpp::R_ARM_THM_CALL
:
6417 case elfcpp::R_ARM_THM_JUMP24
:
6418 case elfcpp::R_ARM_THM_XPC22
:
6420 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
6421 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
6422 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
6423 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
6424 return RelocFuncs::thumb32_branch_offset(upper_insn
, lower_insn
);
6427 case elfcpp::R_ARM_THM_JUMP19
:
6429 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
6430 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
6431 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
6432 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
6433 return RelocFuncs::thumb32_cond_branch_offset(upper_insn
, lower_insn
);
6441 // A class to handle the PLT data.
6443 template<bool big_endian
>
6444 class Output_data_plt_arm
: public Output_section_data
6447 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, big_endian
>
6450 Output_data_plt_arm(Layout
*, Output_data_space
*);
6452 // Add an entry to the PLT.
6454 add_entry(Symbol
* gsym
);
6456 // Return the .rel.plt section data.
6457 const Reloc_section
*
6459 { return this->rel_
; }
6463 do_adjust_output_section(Output_section
* os
);
6465 // Write to a map file.
6467 do_print_to_mapfile(Mapfile
* mapfile
) const
6468 { mapfile
->print_output_data(this, _("** PLT")); }
6471 // Template for the first PLT entry.
6472 static const uint32_t first_plt_entry
[5];
6474 // Template for subsequent PLT entries.
6475 static const uint32_t plt_entry
[3];
6477 // Set the final size.
6479 set_final_data_size()
6481 this->set_data_size(sizeof(first_plt_entry
)
6482 + this->count_
* sizeof(plt_entry
));
6485 // Write out the PLT data.
6487 do_write(Output_file
*);
6489 // The reloc section.
6490 Reloc_section
* rel_
;
6491 // The .got.plt section.
6492 Output_data_space
* got_plt_
;
6493 // The number of PLT entries.
6494 unsigned int count_
;
6497 // Create the PLT section. The ordinary .got section is an argument,
6498 // since we need to refer to the start. We also create our own .got
6499 // section just for PLT entries.
6501 template<bool big_endian
>
6502 Output_data_plt_arm
<big_endian
>::Output_data_plt_arm(Layout
* layout
,
6503 Output_data_space
* got_plt
)
6504 : Output_section_data(4), got_plt_(got_plt
), count_(0)
6506 this->rel_
= new Reloc_section(false);
6507 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
6508 elfcpp::SHF_ALLOC
, this->rel_
, true, false,
6512 template<bool big_endian
>
6514 Output_data_plt_arm
<big_endian
>::do_adjust_output_section(Output_section
* os
)
6519 // Add an entry to the PLT.
6521 template<bool big_endian
>
6523 Output_data_plt_arm
<big_endian
>::add_entry(Symbol
* gsym
)
6525 gold_assert(!gsym
->has_plt_offset());
6527 // Note that when setting the PLT offset we skip the initial
6528 // reserved PLT entry.
6529 gsym
->set_plt_offset((this->count_
) * sizeof(plt_entry
)
6530 + sizeof(first_plt_entry
));
6534 section_offset_type got_offset
= this->got_plt_
->current_data_size();
6536 // Every PLT entry needs a GOT entry which points back to the PLT
6537 // entry (this will be changed by the dynamic linker, normally
6538 // lazily when the function is called).
6539 this->got_plt_
->set_current_data_size(got_offset
+ 4);
6541 // Every PLT entry needs a reloc.
6542 gsym
->set_needs_dynsym_entry();
6543 this->rel_
->add_global(gsym
, elfcpp::R_ARM_JUMP_SLOT
, this->got_plt_
,
6546 // Note that we don't need to save the symbol. The contents of the
6547 // PLT are independent of which symbols are used. The symbols only
6548 // appear in the relocations.
6552 // FIXME: This is not very flexible. Right now this has only been tested
6553 // on armv5te. If we are to support additional architecture features like
6554 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
6556 // The first entry in the PLT.
6557 template<bool big_endian
>
6558 const uint32_t Output_data_plt_arm
<big_endian
>::first_plt_entry
[5] =
6560 0xe52de004, // str lr, [sp, #-4]!
6561 0xe59fe004, // ldr lr, [pc, #4]
6562 0xe08fe00e, // add lr, pc, lr
6563 0xe5bef008, // ldr pc, [lr, #8]!
6564 0x00000000, // &GOT[0] - .
6567 // Subsequent entries in the PLT.
6569 template<bool big_endian
>
6570 const uint32_t Output_data_plt_arm
<big_endian
>::plt_entry
[3] =
6572 0xe28fc600, // add ip, pc, #0xNN00000
6573 0xe28cca00, // add ip, ip, #0xNN000
6574 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
6577 // Write out the PLT. This uses the hand-coded instructions above,
6578 // and adjusts them as needed. This is all specified by the arm ELF
6579 // Processor Supplement.
6581 template<bool big_endian
>
6583 Output_data_plt_arm
<big_endian
>::do_write(Output_file
* of
)
6585 const off_t offset
= this->offset();
6586 const section_size_type oview_size
=
6587 convert_to_section_size_type(this->data_size());
6588 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
6590 const off_t got_file_offset
= this->got_plt_
->offset();
6591 const section_size_type got_size
=
6592 convert_to_section_size_type(this->got_plt_
->data_size());
6593 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
6595 unsigned char* pov
= oview
;
6597 Arm_address plt_address
= this->address();
6598 Arm_address got_address
= this->got_plt_
->address();
6600 // Write first PLT entry. All but the last word are constants.
6601 const size_t num_first_plt_words
= (sizeof(first_plt_entry
)
6602 / sizeof(plt_entry
[0]));
6603 for (size_t i
= 0; i
< num_first_plt_words
- 1; i
++)
6604 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ i
* 4, first_plt_entry
[i
]);
6605 // Last word in first PLT entry is &GOT[0] - .
6606 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 16,
6607 got_address
- (plt_address
+ 16));
6608 pov
+= sizeof(first_plt_entry
);
6610 unsigned char* got_pov
= got_view
;
6612 memset(got_pov
, 0, 12);
6615 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
6616 unsigned int plt_offset
= sizeof(first_plt_entry
);
6617 unsigned int plt_rel_offset
= 0;
6618 unsigned int got_offset
= 12;
6619 const unsigned int count
= this->count_
;
6620 for (unsigned int i
= 0;
6623 pov
+= sizeof(plt_entry
),
6625 plt_offset
+= sizeof(plt_entry
),
6626 plt_rel_offset
+= rel_size
,
6629 // Set and adjust the PLT entry itself.
6630 int32_t offset
= ((got_address
+ got_offset
)
6631 - (plt_address
+ plt_offset
+ 8));
6633 gold_assert(offset
>= 0 && offset
< 0x0fffffff);
6634 uint32_t plt_insn0
= plt_entry
[0] | ((offset
>> 20) & 0xff);
6635 elfcpp::Swap
<32, big_endian
>::writeval(pov
, plt_insn0
);
6636 uint32_t plt_insn1
= plt_entry
[1] | ((offset
>> 12) & 0xff);
6637 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 4, plt_insn1
);
6638 uint32_t plt_insn2
= plt_entry
[2] | (offset
& 0xfff);
6639 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 8, plt_insn2
);
6641 // Set the entry in the GOT.
6642 elfcpp::Swap
<32, big_endian
>::writeval(got_pov
, plt_address
);
6645 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
6646 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
6648 of
->write_output_view(offset
, oview_size
, oview
);
6649 of
->write_output_view(got_file_offset
, got_size
, got_view
);
6652 // Create a PLT entry for a global symbol.
6654 template<bool big_endian
>
6656 Target_arm
<big_endian
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
6659 if (gsym
->has_plt_offset())
6662 if (this->plt_
== NULL
)
6664 // Create the GOT sections first.
6665 this->got_section(symtab
, layout
);
6667 this->plt_
= new Output_data_plt_arm
<big_endian
>(layout
, this->got_plt_
);
6668 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
6670 | elfcpp::SHF_EXECINSTR
),
6671 this->plt_
, false, false, false, false);
6673 this->plt_
->add_entry(gsym
);
6676 // Report an unsupported relocation against a local symbol.
6678 template<bool big_endian
>
6680 Target_arm
<big_endian
>::Scan::unsupported_reloc_local(
6681 Sized_relobj
<32, big_endian
>* object
,
6682 unsigned int r_type
)
6684 gold_error(_("%s: unsupported reloc %u against local symbol"),
6685 object
->name().c_str(), r_type
);
6688 // We are about to emit a dynamic relocation of type R_TYPE. If the
6689 // dynamic linker does not support it, issue an error. The GNU linker
6690 // only issues a non-PIC error for an allocated read-only section.
6691 // Here we know the section is allocated, but we don't know that it is
6692 // read-only. But we check for all the relocation types which the
6693 // glibc dynamic linker supports, so it seems appropriate to issue an
6694 // error even if the section is not read-only.
6696 template<bool big_endian
>
6698 Target_arm
<big_endian
>::Scan::check_non_pic(Relobj
* object
,
6699 unsigned int r_type
)
6703 // These are the relocation types supported by glibc for ARM.
6704 case elfcpp::R_ARM_RELATIVE
:
6705 case elfcpp::R_ARM_COPY
:
6706 case elfcpp::R_ARM_GLOB_DAT
:
6707 case elfcpp::R_ARM_JUMP_SLOT
:
6708 case elfcpp::R_ARM_ABS32
:
6709 case elfcpp::R_ARM_ABS32_NOI
:
6710 case elfcpp::R_ARM_PC24
:
6711 // FIXME: The following 3 types are not supported by Android's dynamic
6713 case elfcpp::R_ARM_TLS_DTPMOD32
:
6714 case elfcpp::R_ARM_TLS_DTPOFF32
:
6715 case elfcpp::R_ARM_TLS_TPOFF32
:
6720 // This prevents us from issuing more than one error per reloc
6721 // section. But we can still wind up issuing more than one
6722 // error per object file.
6723 if (this->issued_non_pic_error_
)
6725 const Arm_reloc_property
* reloc_property
=
6726 arm_reloc_property_table
->get_reloc_property(r_type
);
6727 gold_assert(reloc_property
!= NULL
);
6728 object
->error(_("requires unsupported dynamic reloc %s; "
6729 "recompile with -fPIC"),
6730 reloc_property
->name().c_str());
6731 this->issued_non_pic_error_
= true;
6735 case elfcpp::R_ARM_NONE
:
6740 // Scan a relocation for a local symbol.
6741 // FIXME: This only handles a subset of relocation types used by Android
6742 // on ARM v5te devices.
6744 template<bool big_endian
>
6746 Target_arm
<big_endian
>::Scan::local(Symbol_table
* symtab
,
6749 Sized_relobj
<32, big_endian
>* object
,
6750 unsigned int data_shndx
,
6751 Output_section
* output_section
,
6752 const elfcpp::Rel
<32, big_endian
>& reloc
,
6753 unsigned int r_type
,
6754 const elfcpp::Sym
<32, big_endian
>& lsym
)
6756 r_type
= get_real_reloc_type(r_type
);
6759 case elfcpp::R_ARM_NONE
:
6760 case elfcpp::R_ARM_V4BX
:
6761 case elfcpp::R_ARM_GNU_VTENTRY
:
6762 case elfcpp::R_ARM_GNU_VTINHERIT
:
6765 case elfcpp::R_ARM_ABS32
:
6766 case elfcpp::R_ARM_ABS32_NOI
:
6767 // If building a shared library (or a position-independent
6768 // executable), we need to create a dynamic relocation for
6769 // this location. The relocation applied at link time will
6770 // apply the link-time value, so we flag the location with
6771 // an R_ARM_RELATIVE relocation so the dynamic loader can
6772 // relocate it easily.
6773 if (parameters
->options().output_is_position_independent())
6775 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
6776 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
6777 // If we are to add more other reloc types than R_ARM_ABS32,
6778 // we need to add check_non_pic(object, r_type) here.
6779 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_ARM_RELATIVE
,
6780 output_section
, data_shndx
,
6781 reloc
.get_r_offset());
6785 case elfcpp::R_ARM_ABS16
:
6786 case elfcpp::R_ARM_ABS12
:
6787 case elfcpp::R_ARM_THM_ABS5
:
6788 case elfcpp::R_ARM_ABS8
:
6789 case elfcpp::R_ARM_BASE_ABS
:
6790 case elfcpp::R_ARM_MOVW_ABS_NC
:
6791 case elfcpp::R_ARM_MOVT_ABS
:
6792 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
6793 case elfcpp::R_ARM_THM_MOVT_ABS
:
6794 // If building a shared library (or a position-independent
6795 // executable), we need to create a dynamic relocation for
6796 // this location. Because the addend needs to remain in the
6797 // data section, we need to be careful not to apply this
6798 // relocation statically.
6799 if (parameters
->options().output_is_position_independent())
6801 check_non_pic(object
, r_type
);
6802 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
6803 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
6804 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
6805 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
6806 data_shndx
, reloc
.get_r_offset());
6809 gold_assert(lsym
.get_st_value() == 0);
6810 unsigned int shndx
= lsym
.get_st_shndx();
6812 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
6815 object
->error(_("section symbol %u has bad shndx %u"),
6818 rel_dyn
->add_local_section(object
, shndx
,
6819 r_type
, output_section
,
6820 data_shndx
, reloc
.get_r_offset());
6825 case elfcpp::R_ARM_PC24
:
6826 case elfcpp::R_ARM_REL32
:
6827 case elfcpp::R_ARM_LDR_PC_G0
:
6828 case elfcpp::R_ARM_SBREL32
:
6829 case elfcpp::R_ARM_THM_CALL
:
6830 case elfcpp::R_ARM_THM_PC8
:
6831 case elfcpp::R_ARM_BASE_PREL
:
6832 case elfcpp::R_ARM_PLT32
:
6833 case elfcpp::R_ARM_CALL
:
6834 case elfcpp::R_ARM_JUMP24
:
6835 case elfcpp::R_ARM_THM_JUMP24
:
6836 case elfcpp::R_ARM_LDR_SBREL_11_0_NC
:
6837 case elfcpp::R_ARM_ALU_SBREL_19_12_NC
:
6838 case elfcpp::R_ARM_ALU_SBREL_27_20_CK
:
6839 case elfcpp::R_ARM_SBREL31
:
6840 case elfcpp::R_ARM_PREL31
:
6841 case elfcpp::R_ARM_MOVW_PREL_NC
:
6842 case elfcpp::R_ARM_MOVT_PREL
:
6843 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
6844 case elfcpp::R_ARM_THM_MOVT_PREL
:
6845 case elfcpp::R_ARM_THM_JUMP19
:
6846 case elfcpp::R_ARM_THM_JUMP6
:
6847 case elfcpp::R_ARM_THM_ALU_PREL_11_0
:
6848 case elfcpp::R_ARM_THM_PC12
:
6849 case elfcpp::R_ARM_REL32_NOI
:
6850 case elfcpp::R_ARM_ALU_PC_G0_NC
:
6851 case elfcpp::R_ARM_ALU_PC_G0
:
6852 case elfcpp::R_ARM_ALU_PC_G1_NC
:
6853 case elfcpp::R_ARM_ALU_PC_G1
:
6854 case elfcpp::R_ARM_ALU_PC_G2
:
6855 case elfcpp::R_ARM_LDR_PC_G1
:
6856 case elfcpp::R_ARM_LDR_PC_G2
:
6857 case elfcpp::R_ARM_LDRS_PC_G0
:
6858 case elfcpp::R_ARM_LDRS_PC_G1
:
6859 case elfcpp::R_ARM_LDRS_PC_G2
:
6860 case elfcpp::R_ARM_LDC_PC_G0
:
6861 case elfcpp::R_ARM_LDC_PC_G1
:
6862 case elfcpp::R_ARM_LDC_PC_G2
:
6863 case elfcpp::R_ARM_ALU_SB_G0_NC
:
6864 case elfcpp::R_ARM_ALU_SB_G0
:
6865 case elfcpp::R_ARM_ALU_SB_G1_NC
:
6866 case elfcpp::R_ARM_ALU_SB_G1
:
6867 case elfcpp::R_ARM_ALU_SB_G2
:
6868 case elfcpp::R_ARM_LDR_SB_G0
:
6869 case elfcpp::R_ARM_LDR_SB_G1
:
6870 case elfcpp::R_ARM_LDR_SB_G2
:
6871 case elfcpp::R_ARM_LDRS_SB_G0
:
6872 case elfcpp::R_ARM_LDRS_SB_G1
:
6873 case elfcpp::R_ARM_LDRS_SB_G2
:
6874 case elfcpp::R_ARM_LDC_SB_G0
:
6875 case elfcpp::R_ARM_LDC_SB_G1
:
6876 case elfcpp::R_ARM_LDC_SB_G2
:
6877 case elfcpp::R_ARM_MOVW_BREL_NC
:
6878 case elfcpp::R_ARM_MOVT_BREL
:
6879 case elfcpp::R_ARM_MOVW_BREL
:
6880 case elfcpp::R_ARM_THM_MOVW_BREL_NC
:
6881 case elfcpp::R_ARM_THM_MOVT_BREL
:
6882 case elfcpp::R_ARM_THM_MOVW_BREL
:
6883 case elfcpp::R_ARM_THM_JUMP11
:
6884 case elfcpp::R_ARM_THM_JUMP8
:
6885 // We don't need to do anything for a relative addressing relocation
6886 // against a local symbol if it does not reference the GOT.
6889 case elfcpp::R_ARM_GOTOFF32
:
6890 case elfcpp::R_ARM_GOTOFF12
:
6891 // We need a GOT section:
6892 target
->got_section(symtab
, layout
);
6895 case elfcpp::R_ARM_GOT_BREL
:
6896 case elfcpp::R_ARM_GOT_PREL
:
6898 // The symbol requires a GOT entry.
6899 Output_data_got
<32, big_endian
>* got
=
6900 target
->got_section(symtab
, layout
);
6901 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
6902 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
6904 // If we are generating a shared object, we need to add a
6905 // dynamic RELATIVE relocation for this symbol's GOT entry.
6906 if (parameters
->options().output_is_position_independent())
6908 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
6909 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
6910 rel_dyn
->add_local_relative(
6911 object
, r_sym
, elfcpp::R_ARM_RELATIVE
, got
,
6912 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
6918 case elfcpp::R_ARM_TARGET1
:
6919 case elfcpp::R_ARM_TARGET2
:
6920 // This should have been mapped to another type already.
6922 case elfcpp::R_ARM_COPY
:
6923 case elfcpp::R_ARM_GLOB_DAT
:
6924 case elfcpp::R_ARM_JUMP_SLOT
:
6925 case elfcpp::R_ARM_RELATIVE
:
6926 // These are relocations which should only be seen by the
6927 // dynamic linker, and should never be seen here.
6928 gold_error(_("%s: unexpected reloc %u in object file"),
6929 object
->name().c_str(), r_type
);
6933 unsupported_reloc_local(object
, r_type
);
6938 // Report an unsupported relocation against a global symbol.
6940 template<bool big_endian
>
6942 Target_arm
<big_endian
>::Scan::unsupported_reloc_global(
6943 Sized_relobj
<32, big_endian
>* object
,
6944 unsigned int r_type
,
6947 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
6948 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
6951 // Scan a relocation for a global symbol.
6953 template<bool big_endian
>
6955 Target_arm
<big_endian
>::Scan::global(Symbol_table
* symtab
,
6958 Sized_relobj
<32, big_endian
>* object
,
6959 unsigned int data_shndx
,
6960 Output_section
* output_section
,
6961 const elfcpp::Rel
<32, big_endian
>& reloc
,
6962 unsigned int r_type
,
6965 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
6966 // section. We check here to avoid creating a dynamic reloc against
6967 // _GLOBAL_OFFSET_TABLE_.
6968 if (!target
->has_got_section()
6969 && strcmp(gsym
->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
6970 target
->got_section(symtab
, layout
);
6972 r_type
= get_real_reloc_type(r_type
);
6975 case elfcpp::R_ARM_NONE
:
6976 case elfcpp::R_ARM_V4BX
:
6977 case elfcpp::R_ARM_GNU_VTENTRY
:
6978 case elfcpp::R_ARM_GNU_VTINHERIT
:
6981 case elfcpp::R_ARM_ABS32
:
6982 case elfcpp::R_ARM_ABS16
:
6983 case elfcpp::R_ARM_ABS12
:
6984 case elfcpp::R_ARM_THM_ABS5
:
6985 case elfcpp::R_ARM_ABS8
:
6986 case elfcpp::R_ARM_BASE_ABS
:
6987 case elfcpp::R_ARM_MOVW_ABS_NC
:
6988 case elfcpp::R_ARM_MOVT_ABS
:
6989 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
6990 case elfcpp::R_ARM_THM_MOVT_ABS
:
6991 case elfcpp::R_ARM_ABS32_NOI
:
6992 // Absolute addressing relocations.
6994 // Make a PLT entry if necessary.
6995 if (this->symbol_needs_plt_entry(gsym
))
6997 target
->make_plt_entry(symtab
, layout
, gsym
);
6998 // Since this is not a PC-relative relocation, we may be
6999 // taking the address of a function. In that case we need to
7000 // set the entry in the dynamic symbol table to the address of
7002 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
7003 gsym
->set_needs_dynsym_value();
7005 // Make a dynamic relocation if necessary.
7006 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
7008 if (gsym
->may_need_copy_reloc())
7010 target
->copy_reloc(symtab
, layout
, object
,
7011 data_shndx
, output_section
, gsym
, reloc
);
7013 else if ((r_type
== elfcpp::R_ARM_ABS32
7014 || r_type
== elfcpp::R_ARM_ABS32_NOI
)
7015 && gsym
->can_use_relative_reloc(false))
7017 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
7018 rel_dyn
->add_global_relative(gsym
, elfcpp::R_ARM_RELATIVE
,
7019 output_section
, object
,
7020 data_shndx
, reloc
.get_r_offset());
7024 check_non_pic(object
, r_type
);
7025 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
7026 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
7027 data_shndx
, reloc
.get_r_offset());
7033 case elfcpp::R_ARM_GOTOFF32
:
7034 case elfcpp::R_ARM_GOTOFF12
:
7035 // We need a GOT section.
7036 target
->got_section(symtab
, layout
);
7039 case elfcpp::R_ARM_REL32
:
7040 case elfcpp::R_ARM_LDR_PC_G0
:
7041 case elfcpp::R_ARM_SBREL32
:
7042 case elfcpp::R_ARM_THM_PC8
:
7043 case elfcpp::R_ARM_BASE_PREL
:
7044 case elfcpp::R_ARM_LDR_SBREL_11_0_NC
:
7045 case elfcpp::R_ARM_ALU_SBREL_19_12_NC
:
7046 case elfcpp::R_ARM_ALU_SBREL_27_20_CK
:
7047 case elfcpp::R_ARM_MOVW_PREL_NC
:
7048 case elfcpp::R_ARM_MOVT_PREL
:
7049 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
7050 case elfcpp::R_ARM_THM_MOVT_PREL
:
7051 case elfcpp::R_ARM_THM_ALU_PREL_11_0
:
7052 case elfcpp::R_ARM_THM_PC12
:
7053 case elfcpp::R_ARM_REL32_NOI
:
7054 case elfcpp::R_ARM_ALU_PC_G0_NC
:
7055 case elfcpp::R_ARM_ALU_PC_G0
:
7056 case elfcpp::R_ARM_ALU_PC_G1_NC
:
7057 case elfcpp::R_ARM_ALU_PC_G1
:
7058 case elfcpp::R_ARM_ALU_PC_G2
:
7059 case elfcpp::R_ARM_LDR_PC_G1
:
7060 case elfcpp::R_ARM_LDR_PC_G2
:
7061 case elfcpp::R_ARM_LDRS_PC_G0
:
7062 case elfcpp::R_ARM_LDRS_PC_G1
:
7063 case elfcpp::R_ARM_LDRS_PC_G2
:
7064 case elfcpp::R_ARM_LDC_PC_G0
:
7065 case elfcpp::R_ARM_LDC_PC_G1
:
7066 case elfcpp::R_ARM_LDC_PC_G2
:
7067 case elfcpp::R_ARM_ALU_SB_G0_NC
:
7068 case elfcpp::R_ARM_ALU_SB_G0
:
7069 case elfcpp::R_ARM_ALU_SB_G1_NC
:
7070 case elfcpp::R_ARM_ALU_SB_G1
:
7071 case elfcpp::R_ARM_ALU_SB_G2
:
7072 case elfcpp::R_ARM_LDR_SB_G0
:
7073 case elfcpp::R_ARM_LDR_SB_G1
:
7074 case elfcpp::R_ARM_LDR_SB_G2
:
7075 case elfcpp::R_ARM_LDRS_SB_G0
:
7076 case elfcpp::R_ARM_LDRS_SB_G1
:
7077 case elfcpp::R_ARM_LDRS_SB_G2
:
7078 case elfcpp::R_ARM_LDC_SB_G0
:
7079 case elfcpp::R_ARM_LDC_SB_G1
:
7080 case elfcpp::R_ARM_LDC_SB_G2
:
7081 case elfcpp::R_ARM_MOVW_BREL_NC
:
7082 case elfcpp::R_ARM_MOVT_BREL
:
7083 case elfcpp::R_ARM_MOVW_BREL
:
7084 case elfcpp::R_ARM_THM_MOVW_BREL_NC
:
7085 case elfcpp::R_ARM_THM_MOVT_BREL
:
7086 case elfcpp::R_ARM_THM_MOVW_BREL
:
7087 // Relative addressing relocations.
7089 // Make a dynamic relocation if necessary.
7090 int flags
= Symbol::NON_PIC_REF
;
7091 if (gsym
->needs_dynamic_reloc(flags
))
7093 if (target
->may_need_copy_reloc(gsym
))
7095 target
->copy_reloc(symtab
, layout
, object
,
7096 data_shndx
, output_section
, gsym
, reloc
);
7100 check_non_pic(object
, r_type
);
7101 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
7102 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
7103 data_shndx
, reloc
.get_r_offset());
7109 case elfcpp::R_ARM_PC24
:
7110 case elfcpp::R_ARM_THM_CALL
:
7111 case elfcpp::R_ARM_PLT32
:
7112 case elfcpp::R_ARM_CALL
:
7113 case elfcpp::R_ARM_JUMP24
:
7114 case elfcpp::R_ARM_THM_JUMP24
:
7115 case elfcpp::R_ARM_SBREL31
:
7116 case elfcpp::R_ARM_PREL31
:
7117 case elfcpp::R_ARM_THM_JUMP19
:
7118 case elfcpp::R_ARM_THM_JUMP6
:
7119 case elfcpp::R_ARM_THM_JUMP11
:
7120 case elfcpp::R_ARM_THM_JUMP8
:
7121 // All the relocation above are branches except for the PREL31 ones.
7122 // A PREL31 relocation can point to a personality function in a shared
7123 // library. In that case we want to use a PLT because we want to
7124 // call the personality routine and the dyanmic linkers we care about
7125 // do not support dynamic PREL31 relocations. An REL31 relocation may
7126 // point to a function whose unwinding behaviour is being described but
7127 // we will not mistakenly generate a PLT for that because we should use
7128 // a local section symbol.
7130 // If the symbol is fully resolved, this is just a relative
7131 // local reloc. Otherwise we need a PLT entry.
7132 if (gsym
->final_value_is_known())
7134 // If building a shared library, we can also skip the PLT entry
7135 // if the symbol is defined in the output file and is protected
7137 if (gsym
->is_defined()
7138 && !gsym
->is_from_dynobj()
7139 && !gsym
->is_preemptible())
7141 target
->make_plt_entry(symtab
, layout
, gsym
);
7144 case elfcpp::R_ARM_GOT_BREL
:
7145 case elfcpp::R_ARM_GOT_ABS
:
7146 case elfcpp::R_ARM_GOT_PREL
:
7148 // The symbol requires a GOT entry.
7149 Output_data_got
<32, big_endian
>* got
=
7150 target
->got_section(symtab
, layout
);
7151 if (gsym
->final_value_is_known())
7152 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
7155 // If this symbol is not fully resolved, we need to add a
7156 // GOT entry with a dynamic relocation.
7157 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
7158 if (gsym
->is_from_dynobj()
7159 || gsym
->is_undefined()
7160 || gsym
->is_preemptible())
7161 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
7162 rel_dyn
, elfcpp::R_ARM_GLOB_DAT
);
7165 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
7166 rel_dyn
->add_global_relative(
7167 gsym
, elfcpp::R_ARM_RELATIVE
, got
,
7168 gsym
->got_offset(GOT_TYPE_STANDARD
));
7174 case elfcpp::R_ARM_TARGET1
:
7175 case elfcpp::R_ARM_TARGET2
:
7176 // These should have been mapped to other types already.
7178 case elfcpp::R_ARM_COPY
:
7179 case elfcpp::R_ARM_GLOB_DAT
:
7180 case elfcpp::R_ARM_JUMP_SLOT
:
7181 case elfcpp::R_ARM_RELATIVE
:
7182 // These are relocations which should only be seen by the
7183 // dynamic linker, and should never be seen here.
7184 gold_error(_("%s: unexpected reloc %u in object file"),
7185 object
->name().c_str(), r_type
);
7189 unsupported_reloc_global(object
, r_type
, gsym
);
7194 // Process relocations for gc.
7196 template<bool big_endian
>
7198 Target_arm
<big_endian
>::gc_process_relocs(Symbol_table
* symtab
,
7200 Sized_relobj
<32, big_endian
>* object
,
7201 unsigned int data_shndx
,
7203 const unsigned char* prelocs
,
7205 Output_section
* output_section
,
7206 bool needs_special_offset_handling
,
7207 size_t local_symbol_count
,
7208 const unsigned char* plocal_symbols
)
7210 typedef Target_arm
<big_endian
> Arm
;
7211 typedef typename Target_arm
<big_endian
>::Scan Scan
;
7213 gold::gc_process_relocs
<32, big_endian
, Arm
, elfcpp::SHT_REL
, Scan
>(
7222 needs_special_offset_handling
,
7227 // Scan relocations for a section.
7229 template<bool big_endian
>
7231 Target_arm
<big_endian
>::scan_relocs(Symbol_table
* symtab
,
7233 Sized_relobj
<32, big_endian
>* object
,
7234 unsigned int data_shndx
,
7235 unsigned int sh_type
,
7236 const unsigned char* prelocs
,
7238 Output_section
* output_section
,
7239 bool needs_special_offset_handling
,
7240 size_t local_symbol_count
,
7241 const unsigned char* plocal_symbols
)
7243 typedef typename Target_arm
<big_endian
>::Scan Scan
;
7244 if (sh_type
== elfcpp::SHT_RELA
)
7246 gold_error(_("%s: unsupported RELA reloc section"),
7247 object
->name().c_str());
7251 gold::scan_relocs
<32, big_endian
, Target_arm
, elfcpp::SHT_REL
, Scan
>(
7260 needs_special_offset_handling
,
7265 // Finalize the sections.
7267 template<bool big_endian
>
7269 Target_arm
<big_endian
>::do_finalize_sections(
7271 const Input_objects
* input_objects
,
7272 Symbol_table
* symtab
)
7274 // Merge processor-specific flags.
7275 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
7276 p
!= input_objects
->relobj_end();
7279 Arm_relobj
<big_endian
>* arm_relobj
=
7280 Arm_relobj
<big_endian
>::as_arm_relobj(*p
);
7281 this->merge_processor_specific_flags(
7283 arm_relobj
->processor_specific_flags());
7284 this->merge_object_attributes(arm_relobj
->name().c_str(),
7285 arm_relobj
->attributes_section_data());
7289 for (Input_objects::Dynobj_iterator p
= input_objects
->dynobj_begin();
7290 p
!= input_objects
->dynobj_end();
7293 Arm_dynobj
<big_endian
>* arm_dynobj
=
7294 Arm_dynobj
<big_endian
>::as_arm_dynobj(*p
);
7295 this->merge_processor_specific_flags(
7297 arm_dynobj
->processor_specific_flags());
7298 this->merge_object_attributes(arm_dynobj
->name().c_str(),
7299 arm_dynobj
->attributes_section_data());
7303 const Object_attribute
* cpu_arch_attr
=
7304 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
7305 if (cpu_arch_attr
->int_value() > elfcpp::TAG_CPU_ARCH_V4
)
7306 this->set_may_use_blx(true);
7308 // Check if we need to use Cortex-A8 workaround.
7309 if (parameters
->options().user_set_fix_cortex_a8())
7310 this->fix_cortex_a8_
= parameters
->options().fix_cortex_a8();
7313 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
7314 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
7316 const Object_attribute
* cpu_arch_profile_attr
=
7317 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile
);
7318 this->fix_cortex_a8_
=
7319 (cpu_arch_attr
->int_value() == elfcpp::TAG_CPU_ARCH_V7
7320 && (cpu_arch_profile_attr
->int_value() == 'A'
7321 || cpu_arch_profile_attr
->int_value() == 0));
7324 // Check if we can use V4BX interworking.
7325 // The V4BX interworking stub contains BX instruction,
7326 // which is not specified for some profiles.
7327 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
7328 && !this->may_use_blx())
7329 gold_error(_("unable to provide V4BX reloc interworking fix up; "
7330 "the target profile does not support BX instruction"));
7332 // Fill in some more dynamic tags.
7333 const Reloc_section
* rel_plt
= (this->plt_
== NULL
7335 : this->plt_
->rel_plt());
7336 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
7337 this->rel_dyn_
, true, false);
7339 // Emit any relocs we saved in an attempt to avoid generating COPY
7341 if (this->copy_relocs_
.any_saved_relocs())
7342 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
7344 // Handle the .ARM.exidx section.
7345 Output_section
* exidx_section
= layout
->find_output_section(".ARM.exidx");
7346 if (exidx_section
!= NULL
7347 && exidx_section
->type() == elfcpp::SHT_ARM_EXIDX
7348 && !parameters
->options().relocatable())
7350 // Create __exidx_start and __exdix_end symbols.
7351 symtab
->define_in_output_data("__exidx_start", NULL
,
7352 Symbol_table::PREDEFINED
,
7353 exidx_section
, 0, 0, elfcpp::STT_OBJECT
,
7354 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
, 0,
7356 symtab
->define_in_output_data("__exidx_end", NULL
,
7357 Symbol_table::PREDEFINED
,
7358 exidx_section
, 0, 0, elfcpp::STT_OBJECT
,
7359 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
, 0,
7362 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
7363 // the .ARM.exidx section.
7364 if (!layout
->script_options()->saw_phdrs_clause())
7366 gold_assert(layout
->find_output_segment(elfcpp::PT_ARM_EXIDX
, 0, 0)
7368 Output_segment
* exidx_segment
=
7369 layout
->make_output_segment(elfcpp::PT_ARM_EXIDX
, elfcpp::PF_R
);
7370 exidx_segment
->add_output_section(exidx_section
, elfcpp::PF_R
,
7375 // Create an .ARM.attributes section if there is not one already.
7376 Output_attributes_section_data
* attributes_section
=
7377 new Output_attributes_section_data(*this->attributes_section_data_
);
7378 layout
->add_output_section_data(".ARM.attributes",
7379 elfcpp::SHT_ARM_ATTRIBUTES
, 0,
7380 attributes_section
, false, false, false,
7384 // Return whether a direct absolute static relocation needs to be applied.
7385 // In cases where Scan::local() or Scan::global() has created
7386 // a dynamic relocation other than R_ARM_RELATIVE, the addend
7387 // of the relocation is carried in the data, and we must not
7388 // apply the static relocation.
7390 template<bool big_endian
>
7392 Target_arm
<big_endian
>::Relocate::should_apply_static_reloc(
7393 const Sized_symbol
<32>* gsym
,
7396 Output_section
* output_section
)
7398 // If the output section is not allocated, then we didn't call
7399 // scan_relocs, we didn't create a dynamic reloc, and we must apply
7401 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
7404 // For local symbols, we will have created a non-RELATIVE dynamic
7405 // relocation only if (a) the output is position independent,
7406 // (b) the relocation is absolute (not pc- or segment-relative), and
7407 // (c) the relocation is not 32 bits wide.
7409 return !(parameters
->options().output_is_position_independent()
7410 && (ref_flags
& Symbol::ABSOLUTE_REF
)
7413 // For global symbols, we use the same helper routines used in the
7414 // scan pass. If we did not create a dynamic relocation, or if we
7415 // created a RELATIVE dynamic relocation, we should apply the static
7417 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
7418 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
7419 && gsym
->can_use_relative_reloc(ref_flags
7420 & Symbol::FUNCTION_CALL
);
7421 return !has_dyn
|| is_rel
;
7424 // Perform a relocation.
7426 template<bool big_endian
>
7428 Target_arm
<big_endian
>::Relocate::relocate(
7429 const Relocate_info
<32, big_endian
>* relinfo
,
7431 Output_section
*output_section
,
7433 const elfcpp::Rel
<32, big_endian
>& rel
,
7434 unsigned int r_type
,
7435 const Sized_symbol
<32>* gsym
,
7436 const Symbol_value
<32>* psymval
,
7437 unsigned char* view
,
7438 Arm_address address
,
7439 section_size_type
/* view_size */ )
7441 typedef Arm_relocate_functions
<big_endian
> Arm_relocate_functions
;
7443 r_type
= get_real_reloc_type(r_type
);
7444 const Arm_reloc_property
* reloc_property
=
7445 arm_reloc_property_table
->get_implemented_static_reloc_property(r_type
);
7446 if (reloc_property
== NULL
)
7448 std::string reloc_name
=
7449 arm_reloc_property_table
->reloc_name_in_error_message(r_type
);
7450 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
7451 _("cannot relocate %s in object file"),
7452 reloc_name
.c_str());
7456 const Arm_relobj
<big_endian
>* object
=
7457 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
7459 // If the final branch target of a relocation is THUMB instruction, this
7460 // is 1. Otherwise it is 0.
7461 Arm_address thumb_bit
= 0;
7462 Symbol_value
<32> symval
;
7463 bool is_weakly_undefined_without_plt
= false;
7464 if (relnum
!= Target_arm
<big_endian
>::fake_relnum_for_stubs
)
7468 // This is a global symbol. Determine if we use PLT and if the
7469 // final target is THUMB.
7470 if (gsym
->use_plt_offset(reloc_is_non_pic(r_type
)))
7472 // This uses a PLT, change the symbol value.
7473 symval
.set_output_value(target
->plt_section()->address()
7474 + gsym
->plt_offset());
7477 else if (gsym
->is_weak_undefined())
7479 // This is a weakly undefined symbol and we do not use PLT
7480 // for this relocation. A branch targeting this symbol will
7481 // be converted into an NOP.
7482 is_weakly_undefined_without_plt
= true;
7486 // Set thumb bit if symbol:
7487 // -Has type STT_ARM_TFUNC or
7488 // -Has type STT_FUNC, is defined and with LSB in value set.
7490 (((gsym
->type() == elfcpp::STT_ARM_TFUNC
)
7491 || (gsym
->type() == elfcpp::STT_FUNC
7492 && !gsym
->is_undefined()
7493 && ((psymval
->value(object
, 0) & 1) != 0)))
7500 // This is a local symbol. Determine if the final target is THUMB.
7501 // We saved this information when all the local symbols were read.
7502 elfcpp::Elf_types
<32>::Elf_WXword r_info
= rel
.get_r_info();
7503 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(r_info
);
7504 thumb_bit
= object
->local_symbol_is_thumb_function(r_sym
) ? 1 : 0;
7509 // This is a fake relocation synthesized for a stub. It does not have
7510 // a real symbol. We just look at the LSB of the symbol value to
7511 // determine if the target is THUMB or not.
7512 thumb_bit
= ((psymval
->value(object
, 0) & 1) != 0);
7515 // Strip LSB if this points to a THUMB target.
7517 && reloc_property
->uses_thumb_bit()
7518 && ((psymval
->value(object
, 0) & 1) != 0))
7520 Arm_address stripped_value
=
7521 psymval
->value(object
, 0) & ~static_cast<Arm_address
>(1);
7522 symval
.set_output_value(stripped_value
);
7526 // Get the GOT offset if needed.
7527 // The GOT pointer points to the end of the GOT section.
7528 // We need to subtract the size of the GOT section to get
7529 // the actual offset to use in the relocation.
7530 bool have_got_offset
= false;
7531 unsigned int got_offset
= 0;
7534 case elfcpp::R_ARM_GOT_BREL
:
7535 case elfcpp::R_ARM_GOT_PREL
:
7538 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
7539 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
7540 - target
->got_size());
7544 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
7545 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
7546 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
7547 - target
->got_size());
7549 have_got_offset
= true;
7556 // To look up relocation stubs, we need to pass the symbol table index of
7558 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
7560 // Get the addressing origin of the output segment defining the
7561 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
7562 Arm_address sym_origin
= 0;
7563 if (reloc_property
->uses_symbol_base())
7565 if (r_type
== elfcpp::R_ARM_BASE_ABS
&& gsym
== NULL
)
7566 // R_ARM_BASE_ABS with the NULL symbol will give the
7567 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
7568 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
7569 sym_origin
= target
->got_plt_section()->address();
7570 else if (gsym
== NULL
)
7572 else if (gsym
->source() == Symbol::IN_OUTPUT_SEGMENT
)
7573 sym_origin
= gsym
->output_segment()->vaddr();
7574 else if (gsym
->source() == Symbol::IN_OUTPUT_DATA
)
7575 sym_origin
= gsym
->output_data()->address();
7577 // TODO: Assumes the segment base to be zero for the global symbols
7578 // till the proper support for the segment-base-relative addressing
7579 // will be implemented. This is consistent with GNU ld.
7582 // For relative addressing relocation, find out the relative address base.
7583 Arm_address relative_address_base
= 0;
7584 switch(reloc_property
->relative_address_base())
7586 case Arm_reloc_property::RAB_NONE
:
7588 case Arm_reloc_property::RAB_B_S
:
7589 relative_address_base
= sym_origin
;
7591 case Arm_reloc_property::RAB_GOT_ORG
:
7592 relative_address_base
= target
->got_plt_section()->address();
7594 case Arm_reloc_property::RAB_P
:
7595 relative_address_base
= address
;
7597 case Arm_reloc_property::RAB_Pa
:
7598 relative_address_base
= address
& 0xfffffffcU
;
7604 typename
Arm_relocate_functions::Status reloc_status
=
7605 Arm_relocate_functions::STATUS_OKAY
;
7606 bool check_overflow
= reloc_property
->checks_overflow();
7609 case elfcpp::R_ARM_NONE
:
7612 case elfcpp::R_ARM_ABS8
:
7613 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7615 reloc_status
= Arm_relocate_functions::abs8(view
, object
, psymval
);
7618 case elfcpp::R_ARM_ABS12
:
7619 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7621 reloc_status
= Arm_relocate_functions::abs12(view
, object
, psymval
);
7624 case elfcpp::R_ARM_ABS16
:
7625 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7627 reloc_status
= Arm_relocate_functions::abs16(view
, object
, psymval
);
7630 case elfcpp::R_ARM_ABS32
:
7631 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
7633 reloc_status
= Arm_relocate_functions::abs32(view
, object
, psymval
,
7637 case elfcpp::R_ARM_ABS32_NOI
:
7638 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
7640 // No thumb bit for this relocation: (S + A)
7641 reloc_status
= Arm_relocate_functions::abs32(view
, object
, psymval
,
7645 case elfcpp::R_ARM_MOVW_ABS_NC
:
7646 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7648 reloc_status
= Arm_relocate_functions::movw(view
, object
, psymval
,
7653 case elfcpp::R_ARM_MOVT_ABS
:
7654 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7656 reloc_status
= Arm_relocate_functions::movt(view
, object
, psymval
, 0);
7659 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
7660 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7662 reloc_status
= Arm_relocate_functions::thm_movw(view
, object
, psymval
,
7663 0, thumb_bit
, false);
7666 case elfcpp::R_ARM_THM_MOVT_ABS
:
7667 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7669 reloc_status
= Arm_relocate_functions::thm_movt(view
, object
,
7673 case elfcpp::R_ARM_MOVW_PREL_NC
:
7674 case elfcpp::R_ARM_MOVW_BREL_NC
:
7675 case elfcpp::R_ARM_MOVW_BREL
:
7677 Arm_relocate_functions::movw(view
, object
, psymval
,
7678 relative_address_base
, thumb_bit
,
7682 case elfcpp::R_ARM_MOVT_PREL
:
7683 case elfcpp::R_ARM_MOVT_BREL
:
7685 Arm_relocate_functions::movt(view
, object
, psymval
,
7686 relative_address_base
);
7689 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
7690 case elfcpp::R_ARM_THM_MOVW_BREL_NC
:
7691 case elfcpp::R_ARM_THM_MOVW_BREL
:
7693 Arm_relocate_functions::thm_movw(view
, object
, psymval
,
7694 relative_address_base
,
7695 thumb_bit
, check_overflow
);
7698 case elfcpp::R_ARM_THM_MOVT_PREL
:
7699 case elfcpp::R_ARM_THM_MOVT_BREL
:
7701 Arm_relocate_functions::thm_movt(view
, object
, psymval
,
7702 relative_address_base
);
7705 case elfcpp::R_ARM_REL32
:
7706 reloc_status
= Arm_relocate_functions::rel32(view
, object
, psymval
,
7707 address
, thumb_bit
);
7710 case elfcpp::R_ARM_THM_ABS5
:
7711 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7713 reloc_status
= Arm_relocate_functions::thm_abs5(view
, object
, psymval
);
7716 // Thumb long branches.
7717 case elfcpp::R_ARM_THM_CALL
:
7718 case elfcpp::R_ARM_THM_XPC22
:
7719 case elfcpp::R_ARM_THM_JUMP24
:
7721 Arm_relocate_functions::thumb_branch_common(
7722 r_type
, relinfo
, view
, gsym
, object
, r_sym
, psymval
, address
,
7723 thumb_bit
, is_weakly_undefined_without_plt
);
7726 case elfcpp::R_ARM_GOTOFF32
:
7728 Arm_address got_origin
;
7729 got_origin
= target
->got_plt_section()->address();
7730 reloc_status
= Arm_relocate_functions::rel32(view
, object
, psymval
,
7731 got_origin
, thumb_bit
);
7735 case elfcpp::R_ARM_BASE_PREL
:
7736 gold_assert(gsym
!= NULL
);
7738 Arm_relocate_functions::base_prel(view
, sym_origin
, address
);
7741 case elfcpp::R_ARM_BASE_ABS
:
7743 if (!should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
7747 reloc_status
= Arm_relocate_functions::base_abs(view
, sym_origin
);
7751 case elfcpp::R_ARM_GOT_BREL
:
7752 gold_assert(have_got_offset
);
7753 reloc_status
= Arm_relocate_functions::got_brel(view
, got_offset
);
7756 case elfcpp::R_ARM_GOT_PREL
:
7757 gold_assert(have_got_offset
);
7758 // Get the address origin for GOT PLT, which is allocated right
7759 // after the GOT section, to calculate an absolute address of
7760 // the symbol GOT entry (got_origin + got_offset).
7761 Arm_address got_origin
;
7762 got_origin
= target
->got_plt_section()->address();
7763 reloc_status
= Arm_relocate_functions::got_prel(view
,
7764 got_origin
+ got_offset
,
7768 case elfcpp::R_ARM_PLT32
:
7769 case elfcpp::R_ARM_CALL
:
7770 case elfcpp::R_ARM_JUMP24
:
7771 case elfcpp::R_ARM_XPC25
:
7772 gold_assert(gsym
== NULL
7773 || gsym
->has_plt_offset()
7774 || gsym
->final_value_is_known()
7775 || (gsym
->is_defined()
7776 && !gsym
->is_from_dynobj()
7777 && !gsym
->is_preemptible()));
7779 Arm_relocate_functions::arm_branch_common(
7780 r_type
, relinfo
, view
, gsym
, object
, r_sym
, psymval
, address
,
7781 thumb_bit
, is_weakly_undefined_without_plt
);
7784 case elfcpp::R_ARM_THM_JUMP19
:
7786 Arm_relocate_functions::thm_jump19(view
, object
, psymval
, address
,
7790 case elfcpp::R_ARM_THM_JUMP6
:
7792 Arm_relocate_functions::thm_jump6(view
, object
, psymval
, address
);
7795 case elfcpp::R_ARM_THM_JUMP8
:
7797 Arm_relocate_functions::thm_jump8(view
, object
, psymval
, address
);
7800 case elfcpp::R_ARM_THM_JUMP11
:
7802 Arm_relocate_functions::thm_jump11(view
, object
, psymval
, address
);
7805 case elfcpp::R_ARM_PREL31
:
7806 reloc_status
= Arm_relocate_functions::prel31(view
, object
, psymval
,
7807 address
, thumb_bit
);
7810 case elfcpp::R_ARM_V4BX
:
7811 if (target
->fix_v4bx() > General_options::FIX_V4BX_NONE
)
7813 const bool is_v4bx_interworking
=
7814 (target
->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
);
7816 Arm_relocate_functions::v4bx(relinfo
, view
, object
, address
,
7817 is_v4bx_interworking
);
7821 case elfcpp::R_ARM_THM_PC8
:
7823 Arm_relocate_functions::thm_pc8(view
, object
, psymval
, address
);
7826 case elfcpp::R_ARM_THM_PC12
:
7828 Arm_relocate_functions::thm_pc12(view
, object
, psymval
, address
);
7831 case elfcpp::R_ARM_THM_ALU_PREL_11_0
:
7833 Arm_relocate_functions::thm_alu11(view
, object
, psymval
, address
,
7837 case elfcpp::R_ARM_ALU_PC_G0_NC
:
7838 case elfcpp::R_ARM_ALU_PC_G0
:
7839 case elfcpp::R_ARM_ALU_PC_G1_NC
:
7840 case elfcpp::R_ARM_ALU_PC_G1
:
7841 case elfcpp::R_ARM_ALU_PC_G2
:
7842 case elfcpp::R_ARM_ALU_SB_G0_NC
:
7843 case elfcpp::R_ARM_ALU_SB_G0
:
7844 case elfcpp::R_ARM_ALU_SB_G1_NC
:
7845 case elfcpp::R_ARM_ALU_SB_G1
:
7846 case elfcpp::R_ARM_ALU_SB_G2
:
7848 Arm_relocate_functions::arm_grp_alu(view
, object
, psymval
,
7849 reloc_property
->group_index(),
7850 relative_address_base
,
7851 thumb_bit
, check_overflow
);
7854 case elfcpp::R_ARM_LDR_PC_G0
:
7855 case elfcpp::R_ARM_LDR_PC_G1
:
7856 case elfcpp::R_ARM_LDR_PC_G2
:
7857 case elfcpp::R_ARM_LDR_SB_G0
:
7858 case elfcpp::R_ARM_LDR_SB_G1
:
7859 case elfcpp::R_ARM_LDR_SB_G2
:
7861 Arm_relocate_functions::arm_grp_ldr(view
, object
, psymval
,
7862 reloc_property
->group_index(),
7863 relative_address_base
);
7866 case elfcpp::R_ARM_LDRS_PC_G0
:
7867 case elfcpp::R_ARM_LDRS_PC_G1
:
7868 case elfcpp::R_ARM_LDRS_PC_G2
:
7869 case elfcpp::R_ARM_LDRS_SB_G0
:
7870 case elfcpp::R_ARM_LDRS_SB_G1
:
7871 case elfcpp::R_ARM_LDRS_SB_G2
:
7873 Arm_relocate_functions::arm_grp_ldrs(view
, object
, psymval
,
7874 reloc_property
->group_index(),
7875 relative_address_base
);
7878 case elfcpp::R_ARM_LDC_PC_G0
:
7879 case elfcpp::R_ARM_LDC_PC_G1
:
7880 case elfcpp::R_ARM_LDC_PC_G2
:
7881 case elfcpp::R_ARM_LDC_SB_G0
:
7882 case elfcpp::R_ARM_LDC_SB_G1
:
7883 case elfcpp::R_ARM_LDC_SB_G2
:
7885 Arm_relocate_functions::arm_grp_ldc(view
, object
, psymval
,
7886 reloc_property
->group_index(),
7887 relative_address_base
);
7894 // Report any errors.
7895 switch (reloc_status
)
7897 case Arm_relocate_functions::STATUS_OKAY
:
7899 case Arm_relocate_functions::STATUS_OVERFLOW
:
7900 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
7901 _("relocation overflow in relocation %u"),
7904 case Arm_relocate_functions::STATUS_BAD_RELOC
:
7905 gold_error_at_location(
7909 _("unexpected opcode while processing relocation %u"),
7919 // Relocate section data.
7921 template<bool big_endian
>
7923 Target_arm
<big_endian
>::relocate_section(
7924 const Relocate_info
<32, big_endian
>* relinfo
,
7925 unsigned int sh_type
,
7926 const unsigned char* prelocs
,
7928 Output_section
* output_section
,
7929 bool needs_special_offset_handling
,
7930 unsigned char* view
,
7931 Arm_address address
,
7932 section_size_type view_size
,
7933 const Reloc_symbol_changes
* reloc_symbol_changes
)
7935 typedef typename Target_arm
<big_endian
>::Relocate Arm_relocate
;
7936 gold_assert(sh_type
== elfcpp::SHT_REL
);
7938 // See if we are relocating a relaxed input section. If so, the view
7939 // covers the whole output section and we need to adjust accordingly.
7940 if (needs_special_offset_handling
)
7942 const Output_relaxed_input_section
* poris
=
7943 output_section
->find_relaxed_input_section(relinfo
->object
,
7944 relinfo
->data_shndx
);
7947 Arm_address section_address
= poris
->address();
7948 section_size_type section_size
= poris
->data_size();
7950 gold_assert((section_address
>= address
)
7951 && ((section_address
+ section_size
)
7952 <= (address
+ view_size
)));
7954 off_t offset
= section_address
- address
;
7957 view_size
= section_size
;
7961 gold::relocate_section
<32, big_endian
, Target_arm
, elfcpp::SHT_REL
,
7968 needs_special_offset_handling
,
7972 reloc_symbol_changes
);
7975 // Return the size of a relocation while scanning during a relocatable
7978 template<bool big_endian
>
7980 Target_arm
<big_endian
>::Relocatable_size_for_reloc::get_size_for_reloc(
7981 unsigned int r_type
,
7984 r_type
= get_real_reloc_type(r_type
);
7985 const Arm_reloc_property
* arp
=
7986 arm_reloc_property_table
->get_implemented_static_reloc_property(r_type
);
7991 std::string reloc_name
=
7992 arm_reloc_property_table
->reloc_name_in_error_message(r_type
);
7993 gold_error(_("%s: unexpected %s in object file"),
7994 object
->name().c_str(), reloc_name
.c_str());
7999 // Scan the relocs during a relocatable link.
8001 template<bool big_endian
>
8003 Target_arm
<big_endian
>::scan_relocatable_relocs(
8004 Symbol_table
* symtab
,
8006 Sized_relobj
<32, big_endian
>* object
,
8007 unsigned int data_shndx
,
8008 unsigned int sh_type
,
8009 const unsigned char* prelocs
,
8011 Output_section
* output_section
,
8012 bool needs_special_offset_handling
,
8013 size_t local_symbol_count
,
8014 const unsigned char* plocal_symbols
,
8015 Relocatable_relocs
* rr
)
8017 gold_assert(sh_type
== elfcpp::SHT_REL
);
8019 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
8020 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
8022 gold::scan_relocatable_relocs
<32, big_endian
, elfcpp::SHT_REL
,
8023 Scan_relocatable_relocs
>(
8031 needs_special_offset_handling
,
8037 // Relocate a section during a relocatable link.
8039 template<bool big_endian
>
8041 Target_arm
<big_endian
>::relocate_for_relocatable(
8042 const Relocate_info
<32, big_endian
>* relinfo
,
8043 unsigned int sh_type
,
8044 const unsigned char* prelocs
,
8046 Output_section
* output_section
,
8047 off_t offset_in_output_section
,
8048 const Relocatable_relocs
* rr
,
8049 unsigned char* view
,
8050 Arm_address view_address
,
8051 section_size_type view_size
,
8052 unsigned char* reloc_view
,
8053 section_size_type reloc_view_size
)
8055 gold_assert(sh_type
== elfcpp::SHT_REL
);
8057 gold::relocate_for_relocatable
<32, big_endian
, elfcpp::SHT_REL
>(
8062 offset_in_output_section
,
8071 // Return the value to use for a dynamic symbol which requires special
8072 // treatment. This is how we support equality comparisons of function
8073 // pointers across shared library boundaries, as described in the
8074 // processor specific ABI supplement.
8076 template<bool big_endian
>
8078 Target_arm
<big_endian
>::do_dynsym_value(const Symbol
* gsym
) const
8080 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
8081 return this->plt_section()->address() + gsym
->plt_offset();
8084 // Map platform-specific relocs to real relocs
8086 template<bool big_endian
>
8088 Target_arm
<big_endian
>::get_real_reloc_type (unsigned int r_type
)
8092 case elfcpp::R_ARM_TARGET1
:
8093 // This is either R_ARM_ABS32 or R_ARM_REL32;
8094 return elfcpp::R_ARM_ABS32
;
8096 case elfcpp::R_ARM_TARGET2
:
8097 // This can be any reloc type but ususally is R_ARM_GOT_PREL
8098 return elfcpp::R_ARM_GOT_PREL
;
8105 // Whether if two EABI versions V1 and V2 are compatible.
8107 template<bool big_endian
>
8109 Target_arm
<big_endian
>::are_eabi_versions_compatible(
8110 elfcpp::Elf_Word v1
,
8111 elfcpp::Elf_Word v2
)
8113 // v4 and v5 are the same spec before and after it was released,
8114 // so allow mixing them.
8115 if ((v1
== elfcpp::EF_ARM_EABI_VER4
&& v2
== elfcpp::EF_ARM_EABI_VER5
)
8116 || (v1
== elfcpp::EF_ARM_EABI_VER5
&& v2
== elfcpp::EF_ARM_EABI_VER4
))
8122 // Combine FLAGS from an input object called NAME and the processor-specific
8123 // flags in the ELF header of the output. Much of this is adapted from the
8124 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
8125 // in bfd/elf32-arm.c.
8127 template<bool big_endian
>
8129 Target_arm
<big_endian
>::merge_processor_specific_flags(
8130 const std::string
& name
,
8131 elfcpp::Elf_Word flags
)
8133 if (this->are_processor_specific_flags_set())
8135 elfcpp::Elf_Word out_flags
= this->processor_specific_flags();
8137 // Nothing to merge if flags equal to those in output.
8138 if (flags
== out_flags
)
8141 // Complain about various flag mismatches.
8142 elfcpp::Elf_Word version1
= elfcpp::arm_eabi_version(flags
);
8143 elfcpp::Elf_Word version2
= elfcpp::arm_eabi_version(out_flags
);
8144 if (!this->are_eabi_versions_compatible(version1
, version2
))
8145 gold_error(_("Source object %s has EABI version %d but output has "
8146 "EABI version %d."),
8148 (flags
& elfcpp::EF_ARM_EABIMASK
) >> 24,
8149 (out_flags
& elfcpp::EF_ARM_EABIMASK
) >> 24);
8153 // If the input is the default architecture and had the default
8154 // flags then do not bother setting the flags for the output
8155 // architecture, instead allow future merges to do this. If no
8156 // future merges ever set these flags then they will retain their
8157 // uninitialised values, which surprise surprise, correspond
8158 // to the default values.
8162 // This is the first time, just copy the flags.
8163 // We only copy the EABI version for now.
8164 this->set_processor_specific_flags(flags
& elfcpp::EF_ARM_EABIMASK
);
8168 // Adjust ELF file header.
8169 template<bool big_endian
>
8171 Target_arm
<big_endian
>::do_adjust_elf_header(
8172 unsigned char* view
,
8175 gold_assert(len
== elfcpp::Elf_sizes
<32>::ehdr_size
);
8177 elfcpp::Ehdr
<32, big_endian
> ehdr(view
);
8178 unsigned char e_ident
[elfcpp::EI_NIDENT
];
8179 memcpy(e_ident
, ehdr
.get_e_ident(), elfcpp::EI_NIDENT
);
8181 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
8182 == elfcpp::EF_ARM_EABI_UNKNOWN
)
8183 e_ident
[elfcpp::EI_OSABI
] = elfcpp::ELFOSABI_ARM
;
8185 e_ident
[elfcpp::EI_OSABI
] = 0;
8186 e_ident
[elfcpp::EI_ABIVERSION
] = 0;
8188 // FIXME: Do EF_ARM_BE8 adjustment.
8190 elfcpp::Ehdr_write
<32, big_endian
> oehdr(view
);
8191 oehdr
.put_e_ident(e_ident
);
8194 // do_make_elf_object to override the same function in the base class.
8195 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
8196 // to store ARM specific information. Hence we need to have our own
8197 // ELF object creation.
8199 template<bool big_endian
>
8201 Target_arm
<big_endian
>::do_make_elf_object(
8202 const std::string
& name
,
8203 Input_file
* input_file
,
8204 off_t offset
, const elfcpp::Ehdr
<32, big_endian
>& ehdr
)
8206 int et
= ehdr
.get_e_type();
8207 if (et
== elfcpp::ET_REL
)
8209 Arm_relobj
<big_endian
>* obj
=
8210 new Arm_relobj
<big_endian
>(name
, input_file
, offset
, ehdr
);
8214 else if (et
== elfcpp::ET_DYN
)
8216 Sized_dynobj
<32, big_endian
>* obj
=
8217 new Arm_dynobj
<big_endian
>(name
, input_file
, offset
, ehdr
);
8223 gold_error(_("%s: unsupported ELF file type %d"),
8229 // Read the architecture from the Tag_also_compatible_with attribute, if any.
8230 // Returns -1 if no architecture could be read.
8231 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
8233 template<bool big_endian
>
8235 Target_arm
<big_endian
>::get_secondary_compatible_arch(
8236 const Attributes_section_data
* pasd
)
8238 const Object_attribute
*known_attributes
=
8239 pasd
->known_attributes(Object_attribute::OBJ_ATTR_PROC
);
8241 // Note: the tag and its argument below are uleb128 values, though
8242 // currently-defined values fit in one byte for each.
8243 const std::string
& sv
=
8244 known_attributes
[elfcpp::Tag_also_compatible_with
].string_value();
8246 && sv
.data()[0] == elfcpp::Tag_CPU_arch
8247 && (sv
.data()[1] & 128) != 128)
8248 return sv
.data()[1];
8250 // This tag is "safely ignorable", so don't complain if it looks funny.
8254 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
8255 // The tag is removed if ARCH is -1.
8256 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
8258 template<bool big_endian
>
8260 Target_arm
<big_endian
>::set_secondary_compatible_arch(
8261 Attributes_section_data
* pasd
,
8264 Object_attribute
*known_attributes
=
8265 pasd
->known_attributes(Object_attribute::OBJ_ATTR_PROC
);
8269 known_attributes
[elfcpp::Tag_also_compatible_with
].set_string_value("");
8273 // Note: the tag and its argument below are uleb128 values, though
8274 // currently-defined values fit in one byte for each.
8276 sv
[0] = elfcpp::Tag_CPU_arch
;
8277 gold_assert(arch
!= 0);
8281 known_attributes
[elfcpp::Tag_also_compatible_with
].set_string_value(sv
);
8284 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
8286 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
8288 template<bool big_endian
>
8290 Target_arm
<big_endian
>::tag_cpu_arch_combine(
8293 int* secondary_compat_out
,
8295 int secondary_compat
)
8297 #define T(X) elfcpp::TAG_CPU_ARCH_##X
8298 static const int v6t2
[] =
8310 static const int v6k
[] =
8323 static const int v7
[] =
8337 static const int v6_m
[] =
8352 static const int v6s_m
[] =
8368 static const int v7e_m
[] =
8385 static const int v4t_plus_v6_m
[] =
8401 T(V4T_PLUS_V6_M
) // V4T plus V6_M.
8403 static const int *comb
[] =
8411 // Pseudo-architecture.
8415 // Check we've not got a higher architecture than we know about.
8417 if (oldtag
>= elfcpp::MAX_TAG_CPU_ARCH
|| newtag
>= elfcpp::MAX_TAG_CPU_ARCH
)
8419 gold_error(_("%s: unknown CPU architecture"), name
);
8423 // Override old tag if we have a Tag_also_compatible_with on the output.
8425 if ((oldtag
== T(V6_M
) && *secondary_compat_out
== T(V4T
))
8426 || (oldtag
== T(V4T
) && *secondary_compat_out
== T(V6_M
)))
8427 oldtag
= T(V4T_PLUS_V6_M
);
8429 // And override the new tag if we have a Tag_also_compatible_with on the
8432 if ((newtag
== T(V6_M
) && secondary_compat
== T(V4T
))
8433 || (newtag
== T(V4T
) && secondary_compat
== T(V6_M
)))
8434 newtag
= T(V4T_PLUS_V6_M
);
8436 // Architectures before V6KZ add features monotonically.
8437 int tagh
= std::max(oldtag
, newtag
);
8438 if (tagh
<= elfcpp::TAG_CPU_ARCH_V6KZ
)
8441 int tagl
= std::min(oldtag
, newtag
);
8442 int result
= comb
[tagh
- T(V6T2
)][tagl
];
8444 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
8445 // as the canonical version.
8446 if (result
== T(V4T_PLUS_V6_M
))
8449 *secondary_compat_out
= T(V6_M
);
8452 *secondary_compat_out
= -1;
8456 gold_error(_("%s: conflicting CPU architectures %d/%d"),
8457 name
, oldtag
, newtag
);
8465 // Helper to print AEABI enum tag value.
8467 template<bool big_endian
>
8469 Target_arm
<big_endian
>::aeabi_enum_name(unsigned int value
)
8471 static const char *aeabi_enum_names
[] =
8472 { "", "variable-size", "32-bit", "" };
8473 const size_t aeabi_enum_names_size
=
8474 sizeof(aeabi_enum_names
) / sizeof(aeabi_enum_names
[0]);
8476 if (value
< aeabi_enum_names_size
)
8477 return std::string(aeabi_enum_names
[value
]);
8481 sprintf(buffer
, "<unknown value %u>", value
);
8482 return std::string(buffer
);
8486 // Return the string value to store in TAG_CPU_name.
8488 template<bool big_endian
>
8490 Target_arm
<big_endian
>::tag_cpu_name_value(unsigned int value
)
8492 static const char *name_table
[] = {
8493 // These aren't real CPU names, but we can't guess
8494 // that from the architecture version alone.
8510 const size_t name_table_size
= sizeof(name_table
) / sizeof(name_table
[0]);
8512 if (value
< name_table_size
)
8513 return std::string(name_table
[value
]);
8517 sprintf(buffer
, "<unknown CPU value %u>", value
);
8518 return std::string(buffer
);
8522 // Merge object attributes from input file called NAME with those of the
8523 // output. The input object attributes are in the object pointed by PASD.
8525 template<bool big_endian
>
8527 Target_arm
<big_endian
>::merge_object_attributes(
8529 const Attributes_section_data
* pasd
)
8531 // Return if there is no attributes section data.
8535 // If output has no object attributes, just copy.
8536 if (this->attributes_section_data_
== NULL
)
8538 this->attributes_section_data_
= new Attributes_section_data(*pasd
);
8542 const int vendor
= Object_attribute::OBJ_ATTR_PROC
;
8543 const Object_attribute
* in_attr
= pasd
->known_attributes(vendor
);
8544 Object_attribute
* out_attr
=
8545 this->attributes_section_data_
->known_attributes(vendor
);
8547 // This needs to happen before Tag_ABI_FP_number_model is merged. */
8548 if (in_attr
[elfcpp::Tag_ABI_VFP_args
].int_value()
8549 != out_attr
[elfcpp::Tag_ABI_VFP_args
].int_value())
8551 // Ignore mismatches if the object doesn't use floating point. */
8552 if (out_attr
[elfcpp::Tag_ABI_FP_number_model
].int_value() == 0)
8553 out_attr
[elfcpp::Tag_ABI_VFP_args
].set_int_value(
8554 in_attr
[elfcpp::Tag_ABI_VFP_args
].int_value());
8555 else if (in_attr
[elfcpp::Tag_ABI_FP_number_model
].int_value() != 0)
8556 gold_error(_("%s uses VFP register arguments, output does not"),
8560 for (int i
= 4; i
< Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES
; ++i
)
8562 // Merge this attribute with existing attributes.
8565 case elfcpp::Tag_CPU_raw_name
:
8566 case elfcpp::Tag_CPU_name
:
8567 // These are merged after Tag_CPU_arch.
8570 case elfcpp::Tag_ABI_optimization_goals
:
8571 case elfcpp::Tag_ABI_FP_optimization_goals
:
8572 // Use the first value seen.
8575 case elfcpp::Tag_CPU_arch
:
8577 unsigned int saved_out_attr
= out_attr
->int_value();
8578 // Merge Tag_CPU_arch and Tag_also_compatible_with.
8579 int secondary_compat
=
8580 this->get_secondary_compatible_arch(pasd
);
8581 int secondary_compat_out
=
8582 this->get_secondary_compatible_arch(
8583 this->attributes_section_data_
);
8584 out_attr
[i
].set_int_value(
8585 tag_cpu_arch_combine(name
, out_attr
[i
].int_value(),
8586 &secondary_compat_out
,
8587 in_attr
[i
].int_value(),
8589 this->set_secondary_compatible_arch(this->attributes_section_data_
,
8590 secondary_compat_out
);
8592 // Merge Tag_CPU_name and Tag_CPU_raw_name.
8593 if (out_attr
[i
].int_value() == saved_out_attr
)
8594 ; // Leave the names alone.
8595 else if (out_attr
[i
].int_value() == in_attr
[i
].int_value())
8597 // The output architecture has been changed to match the
8598 // input architecture. Use the input names.
8599 out_attr
[elfcpp::Tag_CPU_name
].set_string_value(
8600 in_attr
[elfcpp::Tag_CPU_name
].string_value());
8601 out_attr
[elfcpp::Tag_CPU_raw_name
].set_string_value(
8602 in_attr
[elfcpp::Tag_CPU_raw_name
].string_value());
8606 out_attr
[elfcpp::Tag_CPU_name
].set_string_value("");
8607 out_attr
[elfcpp::Tag_CPU_raw_name
].set_string_value("");
8610 // If we still don't have a value for Tag_CPU_name,
8611 // make one up now. Tag_CPU_raw_name remains blank.
8612 if (out_attr
[elfcpp::Tag_CPU_name
].string_value() == "")
8614 const std::string cpu_name
=
8615 this->tag_cpu_name_value(out_attr
[i
].int_value());
8616 // FIXME: If we see an unknown CPU, this will be set
8617 // to "<unknown CPU n>", where n is the attribute value.
8618 // This is different from BFD, which leaves the name alone.
8619 out_attr
[elfcpp::Tag_CPU_name
].set_string_value(cpu_name
);
8624 case elfcpp::Tag_ARM_ISA_use
:
8625 case elfcpp::Tag_THUMB_ISA_use
:
8626 case elfcpp::Tag_WMMX_arch
:
8627 case elfcpp::Tag_Advanced_SIMD_arch
:
8628 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
8629 case elfcpp::Tag_ABI_FP_rounding
:
8630 case elfcpp::Tag_ABI_FP_exceptions
:
8631 case elfcpp::Tag_ABI_FP_user_exceptions
:
8632 case elfcpp::Tag_ABI_FP_number_model
:
8633 case elfcpp::Tag_VFP_HP_extension
:
8634 case elfcpp::Tag_CPU_unaligned_access
:
8635 case elfcpp::Tag_T2EE_use
:
8636 case elfcpp::Tag_Virtualization_use
:
8637 case elfcpp::Tag_MPextension_use
:
8638 // Use the largest value specified.
8639 if (in_attr
[i
].int_value() > out_attr
[i
].int_value())
8640 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8643 case elfcpp::Tag_ABI_align8_preserved
:
8644 case elfcpp::Tag_ABI_PCS_RO_data
:
8645 // Use the smallest value specified.
8646 if (in_attr
[i
].int_value() < out_attr
[i
].int_value())
8647 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8650 case elfcpp::Tag_ABI_align8_needed
:
8651 if ((in_attr
[i
].int_value() > 0 || out_attr
[i
].int_value() > 0)
8652 && (in_attr
[elfcpp::Tag_ABI_align8_preserved
].int_value() == 0
8653 || (out_attr
[elfcpp::Tag_ABI_align8_preserved
].int_value()
8656 // This error message should be enabled once all non-conformant
8657 // binaries in the toolchain have had the attributes set
8659 // gold_error(_("output 8-byte data alignment conflicts with %s"),
8663 case elfcpp::Tag_ABI_FP_denormal
:
8664 case elfcpp::Tag_ABI_PCS_GOT_use
:
8666 // These tags have 0 = don't care, 1 = strong requirement,
8667 // 2 = weak requirement.
8668 static const int order_021
[3] = {0, 2, 1};
8670 // Use the "greatest" from the sequence 0, 2, 1, or the largest
8671 // value if greater than 2 (for future-proofing).
8672 if ((in_attr
[i
].int_value() > 2
8673 && in_attr
[i
].int_value() > out_attr
[i
].int_value())
8674 || (in_attr
[i
].int_value() <= 2
8675 && out_attr
[i
].int_value() <= 2
8676 && (order_021
[in_attr
[i
].int_value()]
8677 > order_021
[out_attr
[i
].int_value()])))
8678 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8682 case elfcpp::Tag_CPU_arch_profile
:
8683 if (out_attr
[i
].int_value() != in_attr
[i
].int_value())
8685 // 0 will merge with anything.
8686 // 'A' and 'S' merge to 'A'.
8687 // 'R' and 'S' merge to 'R'.
8688 // 'M' and 'A|R|S' is an error.
8689 if (out_attr
[i
].int_value() == 0
8690 || (out_attr
[i
].int_value() == 'S'
8691 && (in_attr
[i
].int_value() == 'A'
8692 || in_attr
[i
].int_value() == 'R')))
8693 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8694 else if (in_attr
[i
].int_value() == 0
8695 || (in_attr
[i
].int_value() == 'S'
8696 && (out_attr
[i
].int_value() == 'A'
8697 || out_attr
[i
].int_value() == 'R')))
8702 (_("conflicting architecture profiles %c/%c"),
8703 in_attr
[i
].int_value() ? in_attr
[i
].int_value() : '0',
8704 out_attr
[i
].int_value() ? out_attr
[i
].int_value() : '0');
8708 case elfcpp::Tag_VFP_arch
:
8725 // Values greater than 6 aren't defined, so just pick the
8727 if (in_attr
[i
].int_value() > 6
8728 && in_attr
[i
].int_value() > out_attr
[i
].int_value())
8730 *out_attr
= *in_attr
;
8733 // The output uses the superset of input features
8734 // (ISA version) and registers.
8735 int ver
= std::max(vfp_versions
[in_attr
[i
].int_value()].ver
,
8736 vfp_versions
[out_attr
[i
].int_value()].ver
);
8737 int regs
= std::max(vfp_versions
[in_attr
[i
].int_value()].regs
,
8738 vfp_versions
[out_attr
[i
].int_value()].regs
);
8739 // This assumes all possible supersets are also a valid
8742 for (newval
= 6; newval
> 0; newval
--)
8744 if (regs
== vfp_versions
[newval
].regs
8745 && ver
== vfp_versions
[newval
].ver
)
8748 out_attr
[i
].set_int_value(newval
);
8751 case elfcpp::Tag_PCS_config
:
8752 if (out_attr
[i
].int_value() == 0)
8753 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8754 else if (in_attr
[i
].int_value() != 0 && out_attr
[i
].int_value() != 0)
8756 // It's sometimes ok to mix different configs, so this is only
8758 gold_warning(_("%s: conflicting platform configuration"), name
);
8761 case elfcpp::Tag_ABI_PCS_R9_use
:
8762 if (in_attr
[i
].int_value() != out_attr
[i
].int_value()
8763 && out_attr
[i
].int_value() != elfcpp::AEABI_R9_unused
8764 && in_attr
[i
].int_value() != elfcpp::AEABI_R9_unused
)
8766 gold_error(_("%s: conflicting use of R9"), name
);
8768 if (out_attr
[i
].int_value() == elfcpp::AEABI_R9_unused
)
8769 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8771 case elfcpp::Tag_ABI_PCS_RW_data
:
8772 if (in_attr
[i
].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
8773 && (in_attr
[elfcpp::Tag_ABI_PCS_R9_use
].int_value()
8774 != elfcpp::AEABI_R9_SB
)
8775 && (out_attr
[elfcpp::Tag_ABI_PCS_R9_use
].int_value()
8776 != elfcpp::AEABI_R9_unused
))
8778 gold_error(_("%s: SB relative addressing conflicts with use "
8782 // Use the smallest value specified.
8783 if (in_attr
[i
].int_value() < out_attr
[i
].int_value())
8784 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8786 case elfcpp::Tag_ABI_PCS_wchar_t
:
8787 // FIXME: Make it possible to turn off this warning.
8788 if (out_attr
[i
].int_value()
8789 && in_attr
[i
].int_value()
8790 && out_attr
[i
].int_value() != in_attr
[i
].int_value())
8792 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
8793 "use %u-byte wchar_t; use of wchar_t values "
8794 "across objects may fail"),
8795 name
, in_attr
[i
].int_value(),
8796 out_attr
[i
].int_value());
8798 else if (in_attr
[i
].int_value() && !out_attr
[i
].int_value())
8799 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8801 case elfcpp::Tag_ABI_enum_size
:
8802 if (in_attr
[i
].int_value() != elfcpp::AEABI_enum_unused
)
8804 if (out_attr
[i
].int_value() == elfcpp::AEABI_enum_unused
8805 || out_attr
[i
].int_value() == elfcpp::AEABI_enum_forced_wide
)
8807 // The existing object is compatible with anything.
8808 // Use whatever requirements the new object has.
8809 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8811 // FIXME: Make it possible to turn off this warning.
8812 else if (in_attr
[i
].int_value() != elfcpp::AEABI_enum_forced_wide
8813 && out_attr
[i
].int_value() != in_attr
[i
].int_value())
8815 unsigned int in_value
= in_attr
[i
].int_value();
8816 unsigned int out_value
= out_attr
[i
].int_value();
8817 gold_warning(_("%s uses %s enums yet the output is to use "
8818 "%s enums; use of enum values across objects "
8821 this->aeabi_enum_name(in_value
).c_str(),
8822 this->aeabi_enum_name(out_value
).c_str());
8826 case elfcpp::Tag_ABI_VFP_args
:
8829 case elfcpp::Tag_ABI_WMMX_args
:
8830 if (in_attr
[i
].int_value() != out_attr
[i
].int_value())
8832 gold_error(_("%s uses iWMMXt register arguments, output does "
8837 case Object_attribute::Tag_compatibility
:
8838 // Merged in target-independent code.
8840 case elfcpp::Tag_ABI_HardFP_use
:
8841 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
8842 if ((in_attr
[i
].int_value() == 1 && out_attr
[i
].int_value() == 2)
8843 || (in_attr
[i
].int_value() == 2 && out_attr
[i
].int_value() == 1))
8844 out_attr
[i
].set_int_value(3);
8845 else if (in_attr
[i
].int_value() > out_attr
[i
].int_value())
8846 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8848 case elfcpp::Tag_ABI_FP_16bit_format
:
8849 if (in_attr
[i
].int_value() != 0 && out_attr
[i
].int_value() != 0)
8851 if (in_attr
[i
].int_value() != out_attr
[i
].int_value())
8852 gold_error(_("fp16 format mismatch between %s and output"),
8855 if (in_attr
[i
].int_value() != 0)
8856 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
8859 case elfcpp::Tag_nodefaults
:
8860 // This tag is set if it exists, but the value is unused (and is
8861 // typically zero). We don't actually need to do anything here -
8862 // the merge happens automatically when the type flags are merged
8865 case elfcpp::Tag_also_compatible_with
:
8866 // Already done in Tag_CPU_arch.
8868 case elfcpp::Tag_conformance
:
8869 // Keep the attribute if it matches. Throw it away otherwise.
8870 // No attribute means no claim to conform.
8871 if (in_attr
[i
].string_value() != out_attr
[i
].string_value())
8872 out_attr
[i
].set_string_value("");
8877 const char* err_object
= NULL
;
8879 // The "known_obj_attributes" table does contain some undefined
8880 // attributes. Ensure that there are unused.
8881 if (out_attr
[i
].int_value() != 0
8882 || out_attr
[i
].string_value() != "")
8883 err_object
= "output";
8884 else if (in_attr
[i
].int_value() != 0
8885 || in_attr
[i
].string_value() != "")
8888 if (err_object
!= NULL
)
8890 // Attribute numbers >=64 (mod 128) can be safely ignored.
8892 gold_error(_("%s: unknown mandatory EABI object attribute "
8896 gold_warning(_("%s: unknown EABI object attribute %d"),
8900 // Only pass on attributes that match in both inputs.
8901 if (!in_attr
[i
].matches(out_attr
[i
]))
8903 out_attr
[i
].set_int_value(0);
8904 out_attr
[i
].set_string_value("");
8909 // If out_attr was copied from in_attr then it won't have a type yet.
8910 if (in_attr
[i
].type() && !out_attr
[i
].type())
8911 out_attr
[i
].set_type(in_attr
[i
].type());
8914 // Merge Tag_compatibility attributes and any common GNU ones.
8915 this->attributes_section_data_
->merge(name
, pasd
);
8917 // Check for any attributes not known on ARM.
8918 typedef Vendor_object_attributes::Other_attributes Other_attributes
;
8919 const Other_attributes
* in_other_attributes
= pasd
->other_attributes(vendor
);
8920 Other_attributes::const_iterator in_iter
= in_other_attributes
->begin();
8921 Other_attributes
* out_other_attributes
=
8922 this->attributes_section_data_
->other_attributes(vendor
);
8923 Other_attributes::iterator out_iter
= out_other_attributes
->begin();
8925 while (in_iter
!= in_other_attributes
->end()
8926 || out_iter
!= out_other_attributes
->end())
8928 const char* err_object
= NULL
;
8931 // The tags for each list are in numerical order.
8932 // If the tags are equal, then merge.
8933 if (out_iter
!= out_other_attributes
->end()
8934 && (in_iter
== in_other_attributes
->end()
8935 || in_iter
->first
> out_iter
->first
))
8937 // This attribute only exists in output. We can't merge, and we
8938 // don't know what the tag means, so delete it.
8939 err_object
= "output";
8940 err_tag
= out_iter
->first
;
8941 int saved_tag
= out_iter
->first
;
8942 delete out_iter
->second
;
8943 out_other_attributes
->erase(out_iter
);
8944 out_iter
= out_other_attributes
->upper_bound(saved_tag
);
8946 else if (in_iter
!= in_other_attributes
->end()
8947 && (out_iter
!= out_other_attributes
->end()
8948 || in_iter
->first
< out_iter
->first
))
8950 // This attribute only exists in input. We can't merge, and we
8951 // don't know what the tag means, so ignore it.
8953 err_tag
= in_iter
->first
;
8956 else // The tags are equal.
8958 // As present, all attributes in the list are unknown, and
8959 // therefore can't be merged meaningfully.
8960 err_object
= "output";
8961 err_tag
= out_iter
->first
;
8963 // Only pass on attributes that match in both inputs.
8964 if (!in_iter
->second
->matches(*(out_iter
->second
)))
8966 // No match. Delete the attribute.
8967 int saved_tag
= out_iter
->first
;
8968 delete out_iter
->second
;
8969 out_other_attributes
->erase(out_iter
);
8970 out_iter
= out_other_attributes
->upper_bound(saved_tag
);
8974 // Matched. Keep the attribute and move to the next.
8982 // Attribute numbers >=64 (mod 128) can be safely ignored. */
8983 if ((err_tag
& 127) < 64)
8985 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
8986 err_object
, err_tag
);
8990 gold_warning(_("%s: unknown EABI object attribute %d"),
8991 err_object
, err_tag
);
8997 // Stub-generation methods for Target_arm.
8999 // Make a new Arm_input_section object.
9001 template<bool big_endian
>
9002 Arm_input_section
<big_endian
>*
9003 Target_arm
<big_endian
>::new_arm_input_section(
9007 Section_id
sid(relobj
, shndx
);
9009 Arm_input_section
<big_endian
>* arm_input_section
=
9010 new Arm_input_section
<big_endian
>(relobj
, shndx
);
9011 arm_input_section
->init();
9013 // Register new Arm_input_section in map for look-up.
9014 std::pair
<typename
Arm_input_section_map::iterator
, bool> ins
=
9015 this->arm_input_section_map_
.insert(std::make_pair(sid
, arm_input_section
));
9017 // Make sure that it we have not created another Arm_input_section
9018 // for this input section already.
9019 gold_assert(ins
.second
);
9021 return arm_input_section
;
9024 // Find the Arm_input_section object corresponding to the SHNDX-th input
9025 // section of RELOBJ.
9027 template<bool big_endian
>
9028 Arm_input_section
<big_endian
>*
9029 Target_arm
<big_endian
>::find_arm_input_section(
9031 unsigned int shndx
) const
9033 Section_id
sid(relobj
, shndx
);
9034 typename
Arm_input_section_map::const_iterator p
=
9035 this->arm_input_section_map_
.find(sid
);
9036 return (p
!= this->arm_input_section_map_
.end()) ? p
->second
: NULL
;
9039 // Make a new stub table.
9041 template<bool big_endian
>
9042 Stub_table
<big_endian
>*
9043 Target_arm
<big_endian
>::new_stub_table(Arm_input_section
<big_endian
>* owner
)
9045 Stub_table
<big_endian
>* stub_table
=
9046 new Stub_table
<big_endian
>(owner
);
9047 this->stub_tables_
.push_back(stub_table
);
9049 stub_table
->set_address(owner
->address() + owner
->data_size());
9050 stub_table
->set_file_offset(owner
->offset() + owner
->data_size());
9051 stub_table
->finalize_data_size();
9056 // Scan a relocation for stub generation.
9058 template<bool big_endian
>
9060 Target_arm
<big_endian
>::scan_reloc_for_stub(
9061 const Relocate_info
<32, big_endian
>* relinfo
,
9062 unsigned int r_type
,
9063 const Sized_symbol
<32>* gsym
,
9065 const Symbol_value
<32>* psymval
,
9066 elfcpp::Elf_types
<32>::Elf_Swxword addend
,
9067 Arm_address address
)
9069 typedef typename Target_arm
<big_endian
>::Relocate Relocate
;
9071 const Arm_relobj
<big_endian
>* arm_relobj
=
9072 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
9074 if (r_type
== elfcpp::R_ARM_V4BX
)
9076 const uint32_t reg
= (addend
& 0xf);
9077 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
9080 // Try looking up an existing stub from a stub table.
9081 Stub_table
<big_endian
>* stub_table
=
9082 arm_relobj
->stub_table(relinfo
->data_shndx
);
9083 gold_assert(stub_table
!= NULL
);
9085 if (stub_table
->find_arm_v4bx_stub(reg
) == NULL
)
9087 // create a new stub and add it to stub table.
9088 Arm_v4bx_stub
* stub
=
9089 this->stub_factory().make_arm_v4bx_stub(reg
);
9090 gold_assert(stub
!= NULL
);
9091 stub_table
->add_arm_v4bx_stub(stub
);
9098 bool target_is_thumb
;
9099 Symbol_value
<32> symval
;
9102 // This is a global symbol. Determine if we use PLT and if the
9103 // final target is THUMB.
9104 if (gsym
->use_plt_offset(Relocate::reloc_is_non_pic(r_type
)))
9106 // This uses a PLT, change the symbol value.
9107 symval
.set_output_value(this->plt_section()->address()
9108 + gsym
->plt_offset());
9110 target_is_thumb
= false;
9112 else if (gsym
->is_undefined())
9113 // There is no need to generate a stub symbol is undefined.
9118 ((gsym
->type() == elfcpp::STT_ARM_TFUNC
)
9119 || (gsym
->type() == elfcpp::STT_FUNC
9120 && !gsym
->is_undefined()
9121 && ((psymval
->value(arm_relobj
, 0) & 1) != 0)));
9126 // This is a local symbol. Determine if the final target is THUMB.
9127 target_is_thumb
= arm_relobj
->local_symbol_is_thumb_function(r_sym
);
9130 // Strip LSB if this points to a THUMB target.
9131 const Arm_reloc_property
* reloc_property
=
9132 arm_reloc_property_table
->get_implemented_static_reloc_property(r_type
);
9133 gold_assert(reloc_property
!= NULL
);
9135 && reloc_property
->uses_thumb_bit()
9136 && ((psymval
->value(arm_relobj
, 0) & 1) != 0))
9138 Arm_address stripped_value
=
9139 psymval
->value(arm_relobj
, 0) & ~static_cast<Arm_address
>(1);
9140 symval
.set_output_value(stripped_value
);
9144 // Get the symbol value.
9145 Symbol_value
<32>::Value value
= psymval
->value(arm_relobj
, 0);
9147 // Owing to pipelining, the PC relative branches below actually skip
9148 // two instructions when the branch offset is 0.
9149 Arm_address destination
;
9152 case elfcpp::R_ARM_CALL
:
9153 case elfcpp::R_ARM_JUMP24
:
9154 case elfcpp::R_ARM_PLT32
:
9156 destination
= value
+ addend
+ 8;
9158 case elfcpp::R_ARM_THM_CALL
:
9159 case elfcpp::R_ARM_THM_XPC22
:
9160 case elfcpp::R_ARM_THM_JUMP24
:
9161 case elfcpp::R_ARM_THM_JUMP19
:
9163 destination
= value
+ addend
+ 4;
9169 Reloc_stub
* stub
= NULL
;
9170 Stub_type stub_type
=
9171 Reloc_stub::stub_type_for_reloc(r_type
, address
, destination
,
9173 if (stub_type
!= arm_stub_none
)
9175 // Try looking up an existing stub from a stub table.
9176 Stub_table
<big_endian
>* stub_table
=
9177 arm_relobj
->stub_table(relinfo
->data_shndx
);
9178 gold_assert(stub_table
!= NULL
);
9180 // Locate stub by destination.
9181 Reloc_stub::Key
stub_key(stub_type
, gsym
, arm_relobj
, r_sym
, addend
);
9183 // Create a stub if there is not one already
9184 stub
= stub_table
->find_reloc_stub(stub_key
);
9187 // create a new stub and add it to stub table.
9188 stub
= this->stub_factory().make_reloc_stub(stub_type
);
9189 stub_table
->add_reloc_stub(stub
, stub_key
);
9192 // Record the destination address.
9193 stub
->set_destination_address(destination
9194 | (target_is_thumb
? 1 : 0));
9197 // For Cortex-A8, we need to record a relocation at 4K page boundary.
9198 if (this->fix_cortex_a8_
9199 && (r_type
== elfcpp::R_ARM_THM_JUMP24
9200 || r_type
== elfcpp::R_ARM_THM_JUMP19
9201 || r_type
== elfcpp::R_ARM_THM_CALL
9202 || r_type
== elfcpp::R_ARM_THM_XPC22
)
9203 && (address
& 0xfffU
) == 0xffeU
)
9205 // Found a candidate. Note we haven't checked the destination is
9206 // within 4K here: if we do so (and don't create a record) we can't
9207 // tell that a branch should have been relocated when scanning later.
9208 this->cortex_a8_relocs_info_
[address
] =
9209 new Cortex_a8_reloc(stub
, r_type
,
9210 destination
| (target_is_thumb
? 1 : 0));
9214 // This function scans a relocation sections for stub generation.
9215 // The template parameter Relocate must be a class type which provides
9216 // a single function, relocate(), which implements the machine
9217 // specific part of a relocation.
9219 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
9220 // SHT_REL or SHT_RELA.
9222 // PRELOCS points to the relocation data. RELOC_COUNT is the number
9223 // of relocs. OUTPUT_SECTION is the output section.
9224 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
9225 // mapped to output offsets.
9227 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
9228 // VIEW_SIZE is the size. These refer to the input section, unless
9229 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
9230 // the output section.
9232 template<bool big_endian
>
9233 template<int sh_type
>
9235 Target_arm
<big_endian
>::scan_reloc_section_for_stubs(
9236 const Relocate_info
<32, big_endian
>* relinfo
,
9237 const unsigned char* prelocs
,
9239 Output_section
* output_section
,
9240 bool needs_special_offset_handling
,
9241 const unsigned char* view
,
9242 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
9245 typedef typename Reloc_types
<sh_type
, 32, big_endian
>::Reloc Reltype
;
9246 const int reloc_size
=
9247 Reloc_types
<sh_type
, 32, big_endian
>::reloc_size
;
9249 Arm_relobj
<big_endian
>* arm_object
=
9250 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
9251 unsigned int local_count
= arm_object
->local_symbol_count();
9253 Comdat_behavior comdat_behavior
= CB_UNDETERMINED
;
9255 for (size_t i
= 0; i
< reloc_count
; ++i
, prelocs
+= reloc_size
)
9257 Reltype
reloc(prelocs
);
9259 typename
elfcpp::Elf_types
<32>::Elf_WXword r_info
= reloc
.get_r_info();
9260 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(r_info
);
9261 unsigned int r_type
= elfcpp::elf_r_type
<32>(r_info
);
9263 r_type
= this->get_real_reloc_type(r_type
);
9265 // Only a few relocation types need stubs.
9266 if ((r_type
!= elfcpp::R_ARM_CALL
)
9267 && (r_type
!= elfcpp::R_ARM_JUMP24
)
9268 && (r_type
!= elfcpp::R_ARM_PLT32
)
9269 && (r_type
!= elfcpp::R_ARM_THM_CALL
)
9270 && (r_type
!= elfcpp::R_ARM_THM_XPC22
)
9271 && (r_type
!= elfcpp::R_ARM_THM_JUMP24
)
9272 && (r_type
!= elfcpp::R_ARM_THM_JUMP19
)
9273 && (r_type
!= elfcpp::R_ARM_V4BX
))
9276 section_offset_type offset
=
9277 convert_to_section_size_type(reloc
.get_r_offset());
9279 if (needs_special_offset_handling
)
9281 offset
= output_section
->output_offset(relinfo
->object
,
9282 relinfo
->data_shndx
,
9288 if (r_type
== elfcpp::R_ARM_V4BX
)
9290 // Get the BX instruction.
9291 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
9292 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
+ offset
);
9293 elfcpp::Elf_types
<32>::Elf_Swxword insn
=
9294 elfcpp::Swap
<32, big_endian
>::readval(wv
);
9295 this->scan_reloc_for_stub(relinfo
, r_type
, NULL
, 0, NULL
,
9301 Stub_addend_reader
<sh_type
, big_endian
> stub_addend_reader
;
9302 elfcpp::Elf_types
<32>::Elf_Swxword addend
=
9303 stub_addend_reader(r_type
, view
+ offset
, reloc
);
9305 const Sized_symbol
<32>* sym
;
9307 Symbol_value
<32> symval
;
9308 const Symbol_value
<32> *psymval
;
9309 if (r_sym
< local_count
)
9312 psymval
= arm_object
->local_symbol(r_sym
);
9314 // If the local symbol belongs to a section we are discarding,
9315 // and that section is a debug section, try to find the
9316 // corresponding kept section and map this symbol to its
9317 // counterpart in the kept section. The symbol must not
9318 // correspond to a section we are folding.
9320 unsigned int shndx
= psymval
->input_shndx(&is_ordinary
);
9322 && shndx
!= elfcpp::SHN_UNDEF
9323 && !arm_object
->is_section_included(shndx
)
9324 && !(relinfo
->symtab
->is_section_folded(arm_object
, shndx
)))
9326 if (comdat_behavior
== CB_UNDETERMINED
)
9329 arm_object
->section_name(relinfo
->data_shndx
);
9330 comdat_behavior
= get_comdat_behavior(name
.c_str());
9332 if (comdat_behavior
== CB_PRETEND
)
9335 typename
elfcpp::Elf_types
<32>::Elf_Addr value
=
9336 arm_object
->map_to_kept_section(shndx
, &found
);
9338 symval
.set_output_value(value
+ psymval
->input_value());
9340 symval
.set_output_value(0);
9344 symval
.set_output_value(0);
9346 symval
.set_no_output_symtab_entry();
9352 const Symbol
* gsym
= arm_object
->global_symbol(r_sym
);
9353 gold_assert(gsym
!= NULL
);
9354 if (gsym
->is_forwarder())
9355 gsym
= relinfo
->symtab
->resolve_forwards(gsym
);
9357 sym
= static_cast<const Sized_symbol
<32>*>(gsym
);
9358 if (sym
->has_symtab_index())
9359 symval
.set_output_symtab_index(sym
->symtab_index());
9361 symval
.set_no_output_symtab_entry();
9363 // We need to compute the would-be final value of this global
9365 const Symbol_table
* symtab
= relinfo
->symtab
;
9366 const Sized_symbol
<32>* sized_symbol
=
9367 symtab
->get_sized_symbol
<32>(gsym
);
9368 Symbol_table::Compute_final_value_status status
;
9370 symtab
->compute_final_value
<32>(sized_symbol
, &status
);
9372 // Skip this if the symbol has not output section.
9373 if (status
== Symbol_table::CFVS_NO_OUTPUT_SECTION
)
9376 symval
.set_output_value(value
);
9380 // If symbol is a section symbol, we don't know the actual type of
9381 // destination. Give up.
9382 if (psymval
->is_section_symbol())
9385 this->scan_reloc_for_stub(relinfo
, r_type
, sym
, r_sym
, psymval
,
9386 addend
, view_address
+ offset
);
9390 // Scan an input section for stub generation.
9392 template<bool big_endian
>
9394 Target_arm
<big_endian
>::scan_section_for_stubs(
9395 const Relocate_info
<32, big_endian
>* relinfo
,
9396 unsigned int sh_type
,
9397 const unsigned char* prelocs
,
9399 Output_section
* output_section
,
9400 bool needs_special_offset_handling
,
9401 const unsigned char* view
,
9402 Arm_address view_address
,
9403 section_size_type view_size
)
9405 if (sh_type
== elfcpp::SHT_REL
)
9406 this->scan_reloc_section_for_stubs
<elfcpp::SHT_REL
>(
9411 needs_special_offset_handling
,
9415 else if (sh_type
== elfcpp::SHT_RELA
)
9416 // We do not support RELA type relocations yet. This is provided for
9418 this->scan_reloc_section_for_stubs
<elfcpp::SHT_RELA
>(
9423 needs_special_offset_handling
,
9431 // Group input sections for stub generation.
9433 // We goup input sections in an output sections so that the total size,
9434 // including any padding space due to alignment is smaller than GROUP_SIZE
9435 // unless the only input section in group is bigger than GROUP_SIZE already.
9436 // Then an ARM stub table is created to follow the last input section
9437 // in group. For each group an ARM stub table is created an is placed
9438 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
9439 // extend the group after the stub table.
9441 template<bool big_endian
>
9443 Target_arm
<big_endian
>::group_sections(
9445 section_size_type group_size
,
9446 bool stubs_always_after_branch
)
9448 // Group input sections and insert stub table
9449 Layout::Section_list section_list
;
9450 layout
->get_allocated_sections(§ion_list
);
9451 for (Layout::Section_list::const_iterator p
= section_list
.begin();
9452 p
!= section_list
.end();
9455 Arm_output_section
<big_endian
>* output_section
=
9456 Arm_output_section
<big_endian
>::as_arm_output_section(*p
);
9457 output_section
->group_sections(group_size
, stubs_always_after_branch
,
9462 // Relaxation hook. This is where we do stub generation.
9464 template<bool big_endian
>
9466 Target_arm
<big_endian
>::do_relax(
9468 const Input_objects
* input_objects
,
9469 Symbol_table
* symtab
,
9472 // No need to generate stubs if this is a relocatable link.
9473 gold_assert(!parameters
->options().relocatable());
9475 // If this is the first pass, we need to group input sections into
9477 bool done_exidx_fixup
= false;
9480 // Determine the stub group size. The group size is the absolute
9481 // value of the parameter --stub-group-size. If --stub-group-size
9482 // is passed a negative value, we restict stubs to be always after
9483 // the stubbed branches.
9484 int32_t stub_group_size_param
=
9485 parameters
->options().stub_group_size();
9486 bool stubs_always_after_branch
= stub_group_size_param
< 0;
9487 section_size_type stub_group_size
= abs(stub_group_size_param
);
9489 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
9490 // page as the first half of a 32-bit branch straddling two 4K pages.
9491 // This is a crude way of enforcing that.
9492 if (this->fix_cortex_a8_
)
9493 stubs_always_after_branch
= true;
9495 if (stub_group_size
== 1)
9498 // Thumb branch range is +-4MB has to be used as the default
9499 // maximum size (a given section can contain both ARM and Thumb
9500 // code, so the worst case has to be taken into account).
9502 // This value is 24K less than that, which allows for 2025
9503 // 12-byte stubs. If we exceed that, then we will fail to link.
9504 // The user will have to relink with an explicit group size
9506 stub_group_size
= 4170000;
9509 group_sections(layout
, stub_group_size
, stubs_always_after_branch
);
9511 // Also fix .ARM.exidx section coverage.
9512 Output_section
* os
= layout
->find_output_section(".ARM.exidx");
9513 if (os
!= NULL
&& os
->type() == elfcpp::SHT_ARM_EXIDX
)
9515 Arm_output_section
<big_endian
>* exidx_output_section
=
9516 Arm_output_section
<big_endian
>::as_arm_output_section(os
);
9517 this->fix_exidx_coverage(layout
, exidx_output_section
, symtab
);
9518 done_exidx_fixup
= true;
9522 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
9523 // beginning of each relaxation pass, just blow away all the stubs.
9524 // Alternatively, we could selectively remove only the stubs and reloc
9525 // information for code sections that have moved since the last pass.
9526 // That would require more book-keeping.
9527 typedef typename
Stub_table_list::iterator Stub_table_iterator
;
9528 if (this->fix_cortex_a8_
)
9530 // Clear all Cortex-A8 reloc information.
9531 for (typename
Cortex_a8_relocs_info::const_iterator p
=
9532 this->cortex_a8_relocs_info_
.begin();
9533 p
!= this->cortex_a8_relocs_info_
.end();
9536 this->cortex_a8_relocs_info_
.clear();
9538 // Remove all Cortex-A8 stubs.
9539 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
9540 sp
!= this->stub_tables_
.end();
9542 (*sp
)->remove_all_cortex_a8_stubs();
9545 // Scan relocs for relocation stubs
9546 for (Input_objects::Relobj_iterator op
= input_objects
->relobj_begin();
9547 op
!= input_objects
->relobj_end();
9550 Arm_relobj
<big_endian
>* arm_relobj
=
9551 Arm_relobj
<big_endian
>::as_arm_relobj(*op
);
9552 arm_relobj
->scan_sections_for_stubs(this, symtab
, layout
);
9555 // Check all stub tables to see if any of them have their data sizes
9556 // or addresses alignments changed. These are the only things that
9558 bool any_stub_table_changed
= false;
9559 Unordered_set
<const Output_section
*> sections_needing_adjustment
;
9560 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
9561 (sp
!= this->stub_tables_
.end()) && !any_stub_table_changed
;
9564 if ((*sp
)->update_data_size_and_addralign())
9566 // Update data size of stub table owner.
9567 Arm_input_section
<big_endian
>* owner
= (*sp
)->owner();
9568 uint64_t address
= owner
->address();
9569 off_t offset
= owner
->offset();
9570 owner
->reset_address_and_file_offset();
9571 owner
->set_address_and_file_offset(address
, offset
);
9573 sections_needing_adjustment
.insert(owner
->output_section());
9574 any_stub_table_changed
= true;
9578 // Output_section_data::output_section() returns a const pointer but we
9579 // need to update output sections, so we record all output sections needing
9580 // update above and scan the sections here to find out what sections need
9582 for(Layout::Section_list::const_iterator p
= layout
->section_list().begin();
9583 p
!= layout
->section_list().end();
9586 if (sections_needing_adjustment
.find(*p
)
9587 != sections_needing_adjustment
.end())
9588 (*p
)->set_section_offsets_need_adjustment();
9591 // Stop relaxation if no EXIDX fix-up and no stub table change.
9592 bool continue_relaxation
= done_exidx_fixup
|| any_stub_table_changed
;
9594 // Finalize the stubs in the last relaxation pass.
9595 if (!continue_relaxation
)
9597 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
9598 (sp
!= this->stub_tables_
.end()) && !any_stub_table_changed
;
9600 (*sp
)->finalize_stubs();
9602 // Update output local symbol counts of objects if necessary.
9603 for (Input_objects::Relobj_iterator op
= input_objects
->relobj_begin();
9604 op
!= input_objects
->relobj_end();
9607 Arm_relobj
<big_endian
>* arm_relobj
=
9608 Arm_relobj
<big_endian
>::as_arm_relobj(*op
);
9610 // Update output local symbol counts. We need to discard local
9611 // symbols defined in parts of input sections that are discarded by
9613 if (arm_relobj
->output_local_symbol_count_needs_update())
9614 arm_relobj
->update_output_local_symbol_count();
9618 return continue_relaxation
;
9623 template<bool big_endian
>
9625 Target_arm
<big_endian
>::relocate_stub(
9627 const Relocate_info
<32, big_endian
>* relinfo
,
9628 Output_section
* output_section
,
9629 unsigned char* view
,
9630 Arm_address address
,
9631 section_size_type view_size
)
9634 const Stub_template
* stub_template
= stub
->stub_template();
9635 for (size_t i
= 0; i
< stub_template
->reloc_count(); i
++)
9637 size_t reloc_insn_index
= stub_template
->reloc_insn_index(i
);
9638 const Insn_template
* insn
= &stub_template
->insns()[reloc_insn_index
];
9640 unsigned int r_type
= insn
->r_type();
9641 section_size_type reloc_offset
= stub_template
->reloc_offset(i
);
9642 section_size_type reloc_size
= insn
->size();
9643 gold_assert(reloc_offset
+ reloc_size
<= view_size
);
9645 // This is the address of the stub destination.
9646 Arm_address target
= stub
->reloc_target(i
) + insn
->reloc_addend();
9647 Symbol_value
<32> symval
;
9648 symval
.set_output_value(target
);
9650 // Synthesize a fake reloc just in case. We don't have a symbol so
9652 unsigned char reloc_buffer
[elfcpp::Elf_sizes
<32>::rel_size
];
9653 memset(reloc_buffer
, 0, sizeof(reloc_buffer
));
9654 elfcpp::Rel_write
<32, big_endian
> reloc_write(reloc_buffer
);
9655 reloc_write
.put_r_offset(reloc_offset
);
9656 reloc_write
.put_r_info(elfcpp::elf_r_info
<32>(0, r_type
));
9657 elfcpp::Rel
<32, big_endian
> rel(reloc_buffer
);
9659 relocate
.relocate(relinfo
, this, output_section
,
9660 this->fake_relnum_for_stubs
, rel
, r_type
,
9661 NULL
, &symval
, view
+ reloc_offset
,
9662 address
+ reloc_offset
, reloc_size
);
9666 // Determine whether an object attribute tag takes an integer, a
9669 template<bool big_endian
>
9671 Target_arm
<big_endian
>::do_attribute_arg_type(int tag
) const
9673 if (tag
== Object_attribute::Tag_compatibility
)
9674 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
9675 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL
);
9676 else if (tag
== elfcpp::Tag_nodefaults
)
9677 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
9678 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT
);
9679 else if (tag
== elfcpp::Tag_CPU_raw_name
|| tag
== elfcpp::Tag_CPU_name
)
9680 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL
;
9682 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL
;
9684 return ((tag
& 1) != 0
9685 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
9686 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL
);
9689 // Reorder attributes.
9691 // The ABI defines that Tag_conformance should be emitted first, and that
9692 // Tag_nodefaults should be second (if either is defined). This sets those
9693 // two positions, and bumps up the position of all the remaining tags to
9696 template<bool big_endian
>
9698 Target_arm
<big_endian
>::do_attributes_order(int num
) const
9700 // Reorder the known object attributes in output. We want to move
9701 // Tag_conformance to position 4 and Tag_conformance to position 5
9702 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
9704 return elfcpp::Tag_conformance
;
9706 return elfcpp::Tag_nodefaults
;
9707 if ((num
- 2) < elfcpp::Tag_nodefaults
)
9709 if ((num
- 1) < elfcpp::Tag_conformance
)
9714 // Scan a span of THUMB code for Cortex-A8 erratum.
9716 template<bool big_endian
>
9718 Target_arm
<big_endian
>::scan_span_for_cortex_a8_erratum(
9719 Arm_relobj
<big_endian
>* arm_relobj
,
9721 section_size_type span_start
,
9722 section_size_type span_end
,
9723 const unsigned char* view
,
9724 Arm_address address
)
9726 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
9728 // The opcode is BLX.W, BL.W, B.W, Bcc.W
9729 // The branch target is in the same 4KB region as the
9730 // first half of the branch.
9731 // The instruction before the branch is a 32-bit
9732 // length non-branch instruction.
9733 section_size_type i
= span_start
;
9734 bool last_was_32bit
= false;
9735 bool last_was_branch
= false;
9736 while (i
< span_end
)
9738 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
9739 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
+ i
);
9740 uint32_t insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
9741 bool is_blx
= false, is_b
= false;
9742 bool is_bl
= false, is_bcc
= false;
9744 bool insn_32bit
= (insn
& 0xe000) == 0xe000 && (insn
& 0x1800) != 0x0000;
9747 // Load the rest of the insn (in manual-friendly order).
9748 insn
= (insn
<< 16) | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
9750 // Encoding T4: B<c>.W.
9751 is_b
= (insn
& 0xf800d000U
) == 0xf0009000U
;
9752 // Encoding T1: BL<c>.W.
9753 is_bl
= (insn
& 0xf800d000U
) == 0xf000d000U
;
9754 // Encoding T2: BLX<c>.W.
9755 is_blx
= (insn
& 0xf800d000U
) == 0xf000c000U
;
9756 // Encoding T3: B<c>.W (not permitted in IT block).
9757 is_bcc
= ((insn
& 0xf800d000U
) == 0xf0008000U
9758 && (insn
& 0x07f00000U
) != 0x03800000U
);
9761 bool is_32bit_branch
= is_b
|| is_bl
|| is_blx
|| is_bcc
;
9763 // If this instruction is a 32-bit THUMB branch that crosses a 4K
9764 // page boundary and it follows 32-bit non-branch instruction,
9765 // we need to work around.
9767 && ((address
+ i
) & 0xfffU
) == 0xffeU
9769 && !last_was_branch
)
9771 // Check to see if there is a relocation stub for this branch.
9772 bool force_target_arm
= false;
9773 bool force_target_thumb
= false;
9774 const Cortex_a8_reloc
* cortex_a8_reloc
= NULL
;
9775 Cortex_a8_relocs_info::const_iterator p
=
9776 this->cortex_a8_relocs_info_
.find(address
+ i
);
9778 if (p
!= this->cortex_a8_relocs_info_
.end())
9780 cortex_a8_reloc
= p
->second
;
9781 bool target_is_thumb
= (cortex_a8_reloc
->destination() & 1) != 0;
9783 if (cortex_a8_reloc
->r_type() == elfcpp::R_ARM_THM_CALL
9784 && !target_is_thumb
)
9785 force_target_arm
= true;
9786 else if (cortex_a8_reloc
->r_type() == elfcpp::R_ARM_THM_CALL
9788 force_target_thumb
= true;
9792 Stub_type stub_type
= arm_stub_none
;
9794 // Check if we have an offending branch instruction.
9795 uint16_t upper_insn
= (insn
>> 16) & 0xffffU
;
9796 uint16_t lower_insn
= insn
& 0xffffU
;
9797 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
9799 if (cortex_a8_reloc
!= NULL
9800 && cortex_a8_reloc
->reloc_stub() != NULL
)
9801 // We've already made a stub for this instruction, e.g.
9802 // it's a long branch or a Thumb->ARM stub. Assume that
9803 // stub will suffice to work around the A8 erratum (see
9804 // setting of always_after_branch above).
9808 offset
= RelocFuncs::thumb32_cond_branch_offset(upper_insn
,
9810 stub_type
= arm_stub_a8_veneer_b_cond
;
9812 else if (is_b
|| is_bl
|| is_blx
)
9814 offset
= RelocFuncs::thumb32_branch_offset(upper_insn
,
9820 ? arm_stub_a8_veneer_blx
9822 ? arm_stub_a8_veneer_bl
9823 : arm_stub_a8_veneer_b
));
9826 if (stub_type
!= arm_stub_none
)
9828 Arm_address pc_for_insn
= address
+ i
+ 4;
9830 // The original instruction is a BL, but the target is
9831 // an ARM instruction. If we were not making a stub,
9832 // the BL would have been converted to a BLX. Use the
9833 // BLX stub instead in that case.
9834 if (this->may_use_blx() && force_target_arm
9835 && stub_type
== arm_stub_a8_veneer_bl
)
9837 stub_type
= arm_stub_a8_veneer_blx
;
9841 // Conversely, if the original instruction was
9842 // BLX but the target is Thumb mode, use the BL stub.
9843 else if (force_target_thumb
9844 && stub_type
== arm_stub_a8_veneer_blx
)
9846 stub_type
= arm_stub_a8_veneer_bl
;
9854 // If we found a relocation, use the proper destination,
9855 // not the offset in the (unrelocated) instruction.
9856 // Note this is always done if we switched the stub type above.
9857 if (cortex_a8_reloc
!= NULL
)
9858 offset
= (off_t
) (cortex_a8_reloc
->destination() - pc_for_insn
);
9860 Arm_address target
= (pc_for_insn
+ offset
) | (is_blx
? 0 : 1);
9862 // Add a new stub if destination address in in the same page.
9863 if (((address
+ i
) & ~0xfffU
) == (target
& ~0xfffU
))
9865 Cortex_a8_stub
* stub
=
9866 this->stub_factory_
.make_cortex_a8_stub(stub_type
,
9870 Stub_table
<big_endian
>* stub_table
=
9871 arm_relobj
->stub_table(shndx
);
9872 gold_assert(stub_table
!= NULL
);
9873 stub_table
->add_cortex_a8_stub(address
+ i
, stub
);
9878 i
+= insn_32bit
? 4 : 2;
9879 last_was_32bit
= insn_32bit
;
9880 last_was_branch
= is_32bit_branch
;
9884 // Apply the Cortex-A8 workaround.
9886 template<bool big_endian
>
9888 Target_arm
<big_endian
>::apply_cortex_a8_workaround(
9889 const Cortex_a8_stub
* stub
,
9890 Arm_address stub_address
,
9891 unsigned char* insn_view
,
9892 Arm_address insn_address
)
9894 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
9895 Valtype
* wv
= reinterpret_cast<Valtype
*>(insn_view
);
9896 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
9897 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
9898 off_t branch_offset
= stub_address
- (insn_address
+ 4);
9900 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
9901 switch (stub
->stub_template()->type())
9903 case arm_stub_a8_veneer_b_cond
:
9904 gold_assert(!utils::has_overflow
<21>(branch_offset
));
9905 upper_insn
= RelocFuncs::thumb32_cond_branch_upper(upper_insn
,
9907 lower_insn
= RelocFuncs::thumb32_cond_branch_lower(lower_insn
,
9911 case arm_stub_a8_veneer_b
:
9912 case arm_stub_a8_veneer_bl
:
9913 case arm_stub_a8_veneer_blx
:
9914 if ((lower_insn
& 0x5000U
) == 0x4000U
)
9915 // For a BLX instruction, make sure that the relocation is
9916 // rounded up to a word boundary. This follows the semantics of
9917 // the instruction which specifies that bit 1 of the target
9918 // address will come from bit 1 of the base address.
9919 branch_offset
= (branch_offset
+ 2) & ~3;
9921 // Put BRANCH_OFFSET back into the insn.
9922 gold_assert(!utils::has_overflow
<25>(branch_offset
));
9923 upper_insn
= RelocFuncs::thumb32_branch_upper(upper_insn
, branch_offset
);
9924 lower_insn
= RelocFuncs::thumb32_branch_lower(lower_insn
, branch_offset
);
9931 // Put the relocated value back in the object file:
9932 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
9933 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
9936 template<bool big_endian
>
9937 class Target_selector_arm
: public Target_selector
9940 Target_selector_arm()
9941 : Target_selector(elfcpp::EM_ARM
, 32, big_endian
,
9942 (big_endian
? "elf32-bigarm" : "elf32-littlearm"))
9946 do_instantiate_target()
9947 { return new Target_arm
<big_endian
>(); }
9950 // Fix .ARM.exidx section coverage.
9952 template<bool big_endian
>
9954 Target_arm
<big_endian
>::fix_exidx_coverage(
9956 Arm_output_section
<big_endian
>* exidx_section
,
9957 Symbol_table
* symtab
)
9959 // We need to look at all the input sections in output in ascending
9960 // order of of output address. We do that by building a sorted list
9961 // of output sections by addresses. Then we looks at the output sections
9962 // in order. The input sections in an output section are already sorted
9963 // by addresses within the output section.
9965 typedef std::set
<Output_section
*, output_section_address_less_than
>
9966 Sorted_output_section_list
;
9967 Sorted_output_section_list sorted_output_sections
;
9968 Layout::Section_list section_list
;
9969 layout
->get_allocated_sections(§ion_list
);
9970 for (Layout::Section_list::const_iterator p
= section_list
.begin();
9971 p
!= section_list
.end();
9974 // We only care about output sections that contain executable code.
9975 if (((*p
)->flags() & elfcpp::SHF_EXECINSTR
) != 0)
9976 sorted_output_sections
.insert(*p
);
9979 // Go over the output sections in ascending order of output addresses.
9980 typedef typename Arm_output_section
<big_endian
>::Text_section_list
9982 Text_section_list sorted_text_sections
;
9983 for(typename
Sorted_output_section_list::iterator p
=
9984 sorted_output_sections
.begin();
9985 p
!= sorted_output_sections
.end();
9988 Arm_output_section
<big_endian
>* arm_output_section
=
9989 Arm_output_section
<big_endian
>::as_arm_output_section(*p
);
9990 arm_output_section
->append_text_sections_to_list(&sorted_text_sections
);
9993 exidx_section
->fix_exidx_coverage(sorted_text_sections
, symtab
);
9996 Target_selector_arm
<false> target_selector_arm
;
9997 Target_selector_arm
<true> target_selector_armbe
;
9999 } // End anonymous namespace.