* target-reloc.h (scan_relocs): Call scan.local for relocs
[deliverable/binutils-gdb.git] / gold / arm.cc
1 // arm.cc -- arm target support for gold.
2
3 // Copyright 2009, 2010, 2011, 2012 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
7 // bfd/elf32-arm.c.
8
9 // This file is part of gold.
10
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.
15
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.
20
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.
25
26 #include "gold.h"
27
28 #include <cstring>
29 #include <limits>
30 #include <cstdio>
31 #include <string>
32 #include <algorithm>
33 #include <map>
34 #include <utility>
35 #include <set>
36
37 #include "elfcpp.h"
38 #include "parameters.h"
39 #include "reloc.h"
40 #include "arm.h"
41 #include "object.h"
42 #include "symtab.h"
43 #include "layout.h"
44 #include "output.h"
45 #include "copy-relocs.h"
46 #include "target.h"
47 #include "target-reloc.h"
48 #include "target-select.h"
49 #include "tls.h"
50 #include "defstd.h"
51 #include "gc.h"
52 #include "attributes.h"
53 #include "arm-reloc-property.h"
54 #include "nacl.h"
55
56 namespace
57 {
58
59 using namespace gold;
60
61 template<bool big_endian>
62 class Output_data_plt_arm;
63
64 template<bool big_endian>
65 class Output_data_plt_arm_standard;
66
67 template<bool big_endian>
68 class Stub_table;
69
70 template<bool big_endian>
71 class Arm_input_section;
72
73 class Arm_exidx_cantunwind;
74
75 class Arm_exidx_merged_section;
76
77 class Arm_exidx_fixup;
78
79 template<bool big_endian>
80 class Arm_output_section;
81
82 class Arm_exidx_input_section;
83
84 template<bool big_endian>
85 class Arm_relobj;
86
87 template<bool big_endian>
88 class Arm_relocate_functions;
89
90 template<bool big_endian>
91 class Arm_output_data_got;
92
93 template<bool big_endian>
94 class Target_arm;
95
96 // For convenience.
97 typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address;
98
99 // Maximum branch offsets for ARM, THUMB and THUMB2.
100 const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8);
101 const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8);
102 const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4);
103 const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4);
104 const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
105 const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
106
107 // Thread Control Block size.
108 const size_t ARM_TCB_SIZE = 8;
109
110 // The arm target class.
111 //
112 // This is a very simple port of gold for ARM-EABI. It is intended for
113 // supporting Android only for the time being.
114 //
115 // TODOs:
116 // - Implement all static relocation types documented in arm-reloc.def.
117 // - Make PLTs more flexible for different architecture features like
118 // Thumb-2 and BE8.
119 // There are probably a lot more.
120
121 // Ideally we would like to avoid using global variables but this is used
122 // very in many places and sometimes in loops. If we use a function
123 // returning a static instance of Arm_reloc_property_table, it will be very
124 // slow in an threaded environment since the static instance needs to be
125 // locked. The pointer is below initialized in the
126 // Target::do_select_as_default_target() hook so that we do not spend time
127 // building the table if we are not linking ARM objects.
128 //
129 // An alternative is to to process the information in arm-reloc.def in
130 // compilation time and generate a representation of it in PODs only. That
131 // way we can avoid initialization when the linker starts.
132
133 Arm_reloc_property_table* arm_reloc_property_table = NULL;
134
135 // Instruction template class. This class is similar to the insn_sequence
136 // struct in bfd/elf32-arm.c.
137
138 class Insn_template
139 {
140 public:
141 // Types of instruction templates.
142 enum Type
143 {
144 THUMB16_TYPE = 1,
145 // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
146 // templates with class-specific semantics. Currently this is used
147 // only by the Cortex_a8_stub class for handling condition codes in
148 // conditional branches.
149 THUMB16_SPECIAL_TYPE,
150 THUMB32_TYPE,
151 ARM_TYPE,
152 DATA_TYPE
153 };
154
155 // Factory methods to create instruction templates in different formats.
156
157 static const Insn_template
158 thumb16_insn(uint32_t data)
159 { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
160
161 // A Thumb conditional branch, in which the proper condition is inserted
162 // when we build the stub.
163 static const Insn_template
164 thumb16_bcond_insn(uint32_t data)
165 { return Insn_template(data, THUMB16_SPECIAL_TYPE, elfcpp::R_ARM_NONE, 1); }
166
167 static const Insn_template
168 thumb32_insn(uint32_t data)
169 { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); }
170
171 static const Insn_template
172 thumb32_b_insn(uint32_t data, int reloc_addend)
173 {
174 return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24,
175 reloc_addend);
176 }
177
178 static const Insn_template
179 arm_insn(uint32_t data)
180 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); }
181
182 static const Insn_template
183 arm_rel_insn(unsigned data, int reloc_addend)
184 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); }
185
186 static const Insn_template
187 data_word(unsigned data, unsigned int r_type, int reloc_addend)
188 { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); }
189
190 // Accessors. This class is used for read-only objects so no modifiers
191 // are provided.
192
193 uint32_t
194 data() const
195 { return this->data_; }
196
197 // Return the instruction sequence type of this.
198 Type
199 type() const
200 { return this->type_; }
201
202 // Return the ARM relocation type of this.
203 unsigned int
204 r_type() const
205 { return this->r_type_; }
206
207 int32_t
208 reloc_addend() const
209 { return this->reloc_addend_; }
210
211 // Return size of instruction template in bytes.
212 size_t
213 size() const;
214
215 // Return byte-alignment of instruction template.
216 unsigned
217 alignment() const;
218
219 private:
220 // We make the constructor private to ensure that only the factory
221 // methods are used.
222 inline
223 Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend)
224 : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend)
225 { }
226
227 // Instruction specific data. This is used to store information like
228 // some of the instruction bits.
229 uint32_t data_;
230 // Instruction template type.
231 Type type_;
232 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
233 unsigned int r_type_;
234 // Relocation addend.
235 int32_t reloc_addend_;
236 };
237
238 // Macro for generating code to stub types. One entry per long/short
239 // branch stub
240
241 #define DEF_STUBS \
242 DEF_STUB(long_branch_any_any) \
243 DEF_STUB(long_branch_v4t_arm_thumb) \
244 DEF_STUB(long_branch_thumb_only) \
245 DEF_STUB(long_branch_v4t_thumb_thumb) \
246 DEF_STUB(long_branch_v4t_thumb_arm) \
247 DEF_STUB(short_branch_v4t_thumb_arm) \
248 DEF_STUB(long_branch_any_arm_pic) \
249 DEF_STUB(long_branch_any_thumb_pic) \
250 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
251 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
252 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
253 DEF_STUB(long_branch_thumb_only_pic) \
254 DEF_STUB(a8_veneer_b_cond) \
255 DEF_STUB(a8_veneer_b) \
256 DEF_STUB(a8_veneer_bl) \
257 DEF_STUB(a8_veneer_blx) \
258 DEF_STUB(v4_veneer_bx)
259
260 // Stub types.
261
262 #define DEF_STUB(x) arm_stub_##x,
263 typedef enum
264 {
265 arm_stub_none,
266 DEF_STUBS
267
268 // First reloc stub type.
269 arm_stub_reloc_first = arm_stub_long_branch_any_any,
270 // Last reloc stub type.
271 arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic,
272
273 // First Cortex-A8 stub type.
274 arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond,
275 // Last Cortex-A8 stub type.
276 arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
277
278 // Last stub type.
279 arm_stub_type_last = arm_stub_v4_veneer_bx
280 } Stub_type;
281 #undef DEF_STUB
282
283 // Stub template class. Templates are meant to be read-only objects.
284 // A stub template for a stub type contains all read-only attributes
285 // common to all stubs of the same type.
286
287 class Stub_template
288 {
289 public:
290 Stub_template(Stub_type, const Insn_template*, size_t);
291
292 ~Stub_template()
293 { }
294
295 // Return stub type.
296 Stub_type
297 type() const
298 { return this->type_; }
299
300 // Return an array of instruction templates.
301 const Insn_template*
302 insns() const
303 { return this->insns_; }
304
305 // Return size of template in number of instructions.
306 size_t
307 insn_count() const
308 { return this->insn_count_; }
309
310 // Return size of template in bytes.
311 size_t
312 size() const
313 { return this->size_; }
314
315 // Return alignment of the stub template.
316 unsigned
317 alignment() const
318 { return this->alignment_; }
319
320 // Return whether entry point is in thumb mode.
321 bool
322 entry_in_thumb_mode() const
323 { return this->entry_in_thumb_mode_; }
324
325 // Return number of relocations in this template.
326 size_t
327 reloc_count() const
328 { return this->relocs_.size(); }
329
330 // Return index of the I-th instruction with relocation.
331 size_t
332 reloc_insn_index(size_t i) const
333 {
334 gold_assert(i < this->relocs_.size());
335 return this->relocs_[i].first;
336 }
337
338 // Return the offset of the I-th instruction with relocation from the
339 // beginning of the stub.
340 section_size_type
341 reloc_offset(size_t i) const
342 {
343 gold_assert(i < this->relocs_.size());
344 return this->relocs_[i].second;
345 }
346
347 private:
348 // This contains information about an instruction template with a relocation
349 // and its offset from start of stub.
350 typedef std::pair<size_t, section_size_type> Reloc;
351
352 // A Stub_template may not be copied. We want to share templates as much
353 // as possible.
354 Stub_template(const Stub_template&);
355 Stub_template& operator=(const Stub_template&);
356
357 // Stub type.
358 Stub_type type_;
359 // Points to an array of Insn_templates.
360 const Insn_template* insns_;
361 // Number of Insn_templates in insns_[].
362 size_t insn_count_;
363 // Size of templated instructions in bytes.
364 size_t size_;
365 // Alignment of templated instructions.
366 unsigned alignment_;
367 // Flag to indicate if entry is in thumb mode.
368 bool entry_in_thumb_mode_;
369 // A table of reloc instruction indices and offsets. We can find these by
370 // looking at the instruction templates but we pre-compute and then stash
371 // them here for speed.
372 std::vector<Reloc> relocs_;
373 };
374
375 //
376 // A class for code stubs. This is a base class for different type of
377 // stubs used in the ARM target.
378 //
379
380 class Stub
381 {
382 private:
383 static const section_offset_type invalid_offset =
384 static_cast<section_offset_type>(-1);
385
386 public:
387 Stub(const Stub_template* stub_template)
388 : stub_template_(stub_template), offset_(invalid_offset)
389 { }
390
391 virtual
392 ~Stub()
393 { }
394
395 // Return the stub template.
396 const Stub_template*
397 stub_template() const
398 { return this->stub_template_; }
399
400 // Return offset of code stub from beginning of its containing stub table.
401 section_offset_type
402 offset() const
403 {
404 gold_assert(this->offset_ != invalid_offset);
405 return this->offset_;
406 }
407
408 // Set offset of code stub from beginning of its containing stub table.
409 void
410 set_offset(section_offset_type offset)
411 { this->offset_ = offset; }
412
413 // Return the relocation target address of the i-th relocation in the
414 // stub. This must be defined in a child class.
415 Arm_address
416 reloc_target(size_t i)
417 { return this->do_reloc_target(i); }
418
419 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
420 void
421 write(unsigned char* view, section_size_type view_size, bool big_endian)
422 { this->do_write(view, view_size, big_endian); }
423
424 // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
425 // for the i-th instruction.
426 uint16_t
427 thumb16_special(size_t i)
428 { return this->do_thumb16_special(i); }
429
430 protected:
431 // This must be defined in the child class.
432 virtual Arm_address
433 do_reloc_target(size_t) = 0;
434
435 // This may be overridden in the child class.
436 virtual void
437 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
438 {
439 if (big_endian)
440 this->do_fixed_endian_write<true>(view, view_size);
441 else
442 this->do_fixed_endian_write<false>(view, view_size);
443 }
444
445 // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
446 // instruction template.
447 virtual uint16_t
448 do_thumb16_special(size_t)
449 { gold_unreachable(); }
450
451 private:
452 // A template to implement do_write.
453 template<bool big_endian>
454 void inline
455 do_fixed_endian_write(unsigned char*, section_size_type);
456
457 // Its template.
458 const Stub_template* stub_template_;
459 // Offset within the section of containing this stub.
460 section_offset_type offset_;
461 };
462
463 // Reloc stub class. These are stubs we use to fix up relocation because
464 // of limited branch ranges.
465
466 class Reloc_stub : public Stub
467 {
468 public:
469 static const unsigned int invalid_index = static_cast<unsigned int>(-1);
470 // We assume we never jump to this address.
471 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
472
473 // Return destination address.
474 Arm_address
475 destination_address() const
476 {
477 gold_assert(this->destination_address_ != this->invalid_address);
478 return this->destination_address_;
479 }
480
481 // Set destination address.
482 void
483 set_destination_address(Arm_address address)
484 {
485 gold_assert(address != this->invalid_address);
486 this->destination_address_ = address;
487 }
488
489 // Reset destination address.
490 void
491 reset_destination_address()
492 { this->destination_address_ = this->invalid_address; }
493
494 // Determine stub type for a branch of a relocation of R_TYPE going
495 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
496 // the branch target is a thumb instruction. TARGET is used for look
497 // up ARM-specific linker settings.
498 static Stub_type
499 stub_type_for_reloc(unsigned int r_type, Arm_address branch_address,
500 Arm_address branch_target, bool target_is_thumb);
501
502 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
503 // and an addend. Since we treat global and local symbol differently, we
504 // use a Symbol object for a global symbol and a object-index pair for
505 // a local symbol.
506 class Key
507 {
508 public:
509 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
510 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
511 // and R_SYM must not be invalid_index.
512 Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj,
513 unsigned int r_sym, int32_t addend)
514 : stub_type_(stub_type), addend_(addend)
515 {
516 if (symbol != NULL)
517 {
518 this->r_sym_ = Reloc_stub::invalid_index;
519 this->u_.symbol = symbol;
520 }
521 else
522 {
523 gold_assert(relobj != NULL && r_sym != invalid_index);
524 this->r_sym_ = r_sym;
525 this->u_.relobj = relobj;
526 }
527 }
528
529 ~Key()
530 { }
531
532 // Accessors: Keys are meant to be read-only object so no modifiers are
533 // provided.
534
535 // Return stub type.
536 Stub_type
537 stub_type() const
538 { return this->stub_type_; }
539
540 // Return the local symbol index or invalid_index.
541 unsigned int
542 r_sym() const
543 { return this->r_sym_; }
544
545 // Return the symbol if there is one.
546 const Symbol*
547 symbol() const
548 { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
549
550 // Return the relobj if there is one.
551 const Relobj*
552 relobj() const
553 { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
554
555 // Whether this equals to another key k.
556 bool
557 eq(const Key& k) const
558 {
559 return ((this->stub_type_ == k.stub_type_)
560 && (this->r_sym_ == k.r_sym_)
561 && ((this->r_sym_ != Reloc_stub::invalid_index)
562 ? (this->u_.relobj == k.u_.relobj)
563 : (this->u_.symbol == k.u_.symbol))
564 && (this->addend_ == k.addend_));
565 }
566
567 // Return a hash value.
568 size_t
569 hash_value() const
570 {
571 return (this->stub_type_
572 ^ this->r_sym_
573 ^ gold::string_hash<char>(
574 (this->r_sym_ != Reloc_stub::invalid_index)
575 ? this->u_.relobj->name().c_str()
576 : this->u_.symbol->name())
577 ^ this->addend_);
578 }
579
580 // Functors for STL associative containers.
581 struct hash
582 {
583 size_t
584 operator()(const Key& k) const
585 { return k.hash_value(); }
586 };
587
588 struct equal_to
589 {
590 bool
591 operator()(const Key& k1, const Key& k2) const
592 { return k1.eq(k2); }
593 };
594
595 // Name of key. This is mainly for debugging.
596 std::string
597 name() const;
598
599 private:
600 // Stub type.
601 Stub_type stub_type_;
602 // If this is a local symbol, this is the index in the defining object.
603 // Otherwise, it is invalid_index for a global symbol.
604 unsigned int r_sym_;
605 // If r_sym_ is an invalid index, this points to a global symbol.
606 // Otherwise, it points to a relobj. We used the unsized and target
607 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
608 // Arm_relobj, in order to avoid making the stub class a template
609 // as most of the stub machinery is endianness-neutral. However, it
610 // may require a bit of casting done by users of this class.
611 union
612 {
613 const Symbol* symbol;
614 const Relobj* relobj;
615 } u_;
616 // Addend associated with a reloc.
617 int32_t addend_;
618 };
619
620 protected:
621 // Reloc_stubs are created via a stub factory. So these are protected.
622 Reloc_stub(const Stub_template* stub_template)
623 : Stub(stub_template), destination_address_(invalid_address)
624 { }
625
626 ~Reloc_stub()
627 { }
628
629 friend class Stub_factory;
630
631 // Return the relocation target address of the i-th relocation in the
632 // stub.
633 Arm_address
634 do_reloc_target(size_t i)
635 {
636 // All reloc stub have only one relocation.
637 gold_assert(i == 0);
638 return this->destination_address_;
639 }
640
641 private:
642 // Address of destination.
643 Arm_address destination_address_;
644 };
645
646 // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
647 // THUMB branch that meets the following conditions:
648 //
649 // 1. The branch straddles across a page boundary. i.e. lower 12-bit of
650 // branch address is 0xffe.
651 // 2. The branch target address is in the same page as the first word of the
652 // branch.
653 // 3. The branch follows a 32-bit instruction which is not a branch.
654 //
655 // To do the fix up, we need to store the address of the branch instruction
656 // and its target at least. We also need to store the original branch
657 // instruction bits for the condition code in a conditional branch. The
658 // condition code is used in a special instruction template. We also want
659 // to identify input sections needing Cortex-A8 workaround quickly. We store
660 // extra information about object and section index of the code section
661 // containing a branch being fixed up. The information is used to mark
662 // the code section when we finalize the Cortex-A8 stubs.
663 //
664
665 class Cortex_a8_stub : public Stub
666 {
667 public:
668 ~Cortex_a8_stub()
669 { }
670
671 // Return the object of the code section containing the branch being fixed
672 // up.
673 Relobj*
674 relobj() const
675 { return this->relobj_; }
676
677 // Return the section index of the code section containing the branch being
678 // fixed up.
679 unsigned int
680 shndx() const
681 { return this->shndx_; }
682
683 // Return the source address of stub. This is the address of the original
684 // branch instruction. LSB is 1 always set to indicate that it is a THUMB
685 // instruction.
686 Arm_address
687 source_address() const
688 { return this->source_address_; }
689
690 // Return the destination address of the stub. This is the branch taken
691 // address of the original branch instruction. LSB is 1 if it is a THUMB
692 // instruction address.
693 Arm_address
694 destination_address() const
695 { return this->destination_address_; }
696
697 // Return the instruction being fixed up.
698 uint32_t
699 original_insn() const
700 { return this->original_insn_; }
701
702 protected:
703 // Cortex_a8_stubs are created via a stub factory. So these are protected.
704 Cortex_a8_stub(const Stub_template* stub_template, Relobj* relobj,
705 unsigned int shndx, Arm_address source_address,
706 Arm_address destination_address, uint32_t original_insn)
707 : Stub(stub_template), relobj_(relobj), shndx_(shndx),
708 source_address_(source_address | 1U),
709 destination_address_(destination_address),
710 original_insn_(original_insn)
711 { }
712
713 friend class Stub_factory;
714
715 // Return the relocation target address of the i-th relocation in the
716 // stub.
717 Arm_address
718 do_reloc_target(size_t i)
719 {
720 if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond)
721 {
722 // The conditional branch veneer has two relocations.
723 gold_assert(i < 2);
724 return i == 0 ? this->source_address_ + 4 : this->destination_address_;
725 }
726 else
727 {
728 // All other Cortex-A8 stubs have only one relocation.
729 gold_assert(i == 0);
730 return this->destination_address_;
731 }
732 }
733
734 // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
735 uint16_t
736 do_thumb16_special(size_t);
737
738 private:
739 // Object of the code section containing the branch being fixed up.
740 Relobj* relobj_;
741 // Section index of the code section containing the branch begin fixed up.
742 unsigned int shndx_;
743 // Source address of original branch.
744 Arm_address source_address_;
745 // Destination address of the original branch.
746 Arm_address destination_address_;
747 // Original branch instruction. This is needed for copying the condition
748 // code from a condition branch to its stub.
749 uint32_t original_insn_;
750 };
751
752 // ARMv4 BX Rx branch relocation stub class.
753 class Arm_v4bx_stub : public Stub
754 {
755 public:
756 ~Arm_v4bx_stub()
757 { }
758
759 // Return the associated register.
760 uint32_t
761 reg() const
762 { return this->reg_; }
763
764 protected:
765 // Arm V4BX stubs are created via a stub factory. So these are protected.
766 Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg)
767 : Stub(stub_template), reg_(reg)
768 { }
769
770 friend class Stub_factory;
771
772 // Return the relocation target address of the i-th relocation in the
773 // stub.
774 Arm_address
775 do_reloc_target(size_t)
776 { gold_unreachable(); }
777
778 // This may be overridden in the child class.
779 virtual void
780 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
781 {
782 if (big_endian)
783 this->do_fixed_endian_v4bx_write<true>(view, view_size);
784 else
785 this->do_fixed_endian_v4bx_write<false>(view, view_size);
786 }
787
788 private:
789 // A template to implement do_write.
790 template<bool big_endian>
791 void inline
792 do_fixed_endian_v4bx_write(unsigned char* view, section_size_type)
793 {
794 const Insn_template* insns = this->stub_template()->insns();
795 elfcpp::Swap<32, big_endian>::writeval(view,
796 (insns[0].data()
797 + (this->reg_ << 16)));
798 view += insns[0].size();
799 elfcpp::Swap<32, big_endian>::writeval(view,
800 (insns[1].data() + this->reg_));
801 view += insns[1].size();
802 elfcpp::Swap<32, big_endian>::writeval(view,
803 (insns[2].data() + this->reg_));
804 }
805
806 // A register index (r0-r14), which is associated with the stub.
807 uint32_t reg_;
808 };
809
810 // Stub factory class.
811
812 class Stub_factory
813 {
814 public:
815 // Return the unique instance of this class.
816 static const Stub_factory&
817 get_instance()
818 {
819 static Stub_factory singleton;
820 return singleton;
821 }
822
823 // Make a relocation stub.
824 Reloc_stub*
825 make_reloc_stub(Stub_type stub_type) const
826 {
827 gold_assert(stub_type >= arm_stub_reloc_first
828 && stub_type <= arm_stub_reloc_last);
829 return new Reloc_stub(this->stub_templates_[stub_type]);
830 }
831
832 // Make a Cortex-A8 stub.
833 Cortex_a8_stub*
834 make_cortex_a8_stub(Stub_type stub_type, Relobj* relobj, unsigned int shndx,
835 Arm_address source, Arm_address destination,
836 uint32_t original_insn) const
837 {
838 gold_assert(stub_type >= arm_stub_cortex_a8_first
839 && stub_type <= arm_stub_cortex_a8_last);
840 return new Cortex_a8_stub(this->stub_templates_[stub_type], relobj, shndx,
841 source, destination, original_insn);
842 }
843
844 // Make an ARM V4BX relocation stub.
845 // This method creates a stub from the arm_stub_v4_veneer_bx template only.
846 Arm_v4bx_stub*
847 make_arm_v4bx_stub(uint32_t reg) const
848 {
849 gold_assert(reg < 0xf);
850 return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx],
851 reg);
852 }
853
854 private:
855 // Constructor and destructor are protected since we only return a single
856 // instance created in Stub_factory::get_instance().
857
858 Stub_factory();
859
860 // A Stub_factory may not be copied since it is a singleton.
861 Stub_factory(const Stub_factory&);
862 Stub_factory& operator=(Stub_factory&);
863
864 // Stub templates. These are initialized in the constructor.
865 const Stub_template* stub_templates_[arm_stub_type_last+1];
866 };
867
868 // A class to hold stubs for the ARM target.
869
870 template<bool big_endian>
871 class Stub_table : public Output_data
872 {
873 public:
874 Stub_table(Arm_input_section<big_endian>* owner)
875 : Output_data(), owner_(owner), reloc_stubs_(), reloc_stubs_size_(0),
876 reloc_stubs_addralign_(1), cortex_a8_stubs_(), arm_v4bx_stubs_(0xf),
877 prev_data_size_(0), prev_addralign_(1)
878 { }
879
880 ~Stub_table()
881 { }
882
883 // Owner of this stub table.
884 Arm_input_section<big_endian>*
885 owner() const
886 { return this->owner_; }
887
888 // Whether this stub table is empty.
889 bool
890 empty() const
891 {
892 return (this->reloc_stubs_.empty()
893 && this->cortex_a8_stubs_.empty()
894 && this->arm_v4bx_stubs_.empty());
895 }
896
897 // Return the current data size.
898 off_t
899 current_data_size() const
900 { return this->current_data_size_for_child(); }
901
902 // Add a STUB using KEY. The caller is responsible for avoiding addition
903 // if a STUB with the same key has already been added.
904 void
905 add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key)
906 {
907 const Stub_template* stub_template = stub->stub_template();
908 gold_assert(stub_template->type() == key.stub_type());
909 this->reloc_stubs_[key] = stub;
910
911 // Assign stub offset early. We can do this because we never remove
912 // reloc stubs and they are in the beginning of the stub table.
913 uint64_t align = stub_template->alignment();
914 this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_, align);
915 stub->set_offset(this->reloc_stubs_size_);
916 this->reloc_stubs_size_ += stub_template->size();
917 this->reloc_stubs_addralign_ =
918 std::max(this->reloc_stubs_addralign_, align);
919 }
920
921 // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
922 // The caller is responsible for avoiding addition if a STUB with the same
923 // address has already been added.
924 void
925 add_cortex_a8_stub(Arm_address address, Cortex_a8_stub* stub)
926 {
927 std::pair<Arm_address, Cortex_a8_stub*> value(address, stub);
928 this->cortex_a8_stubs_.insert(value);
929 }
930
931 // Add an ARM V4BX relocation stub. A register index will be retrieved
932 // from the stub.
933 void
934 add_arm_v4bx_stub(Arm_v4bx_stub* stub)
935 {
936 gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL);
937 this->arm_v4bx_stubs_[stub->reg()] = stub;
938 }
939
940 // Remove all Cortex-A8 stubs.
941 void
942 remove_all_cortex_a8_stubs();
943
944 // Look up a relocation stub using KEY. Return NULL if there is none.
945 Reloc_stub*
946 find_reloc_stub(const Reloc_stub::Key& key) const
947 {
948 typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
949 return (p != this->reloc_stubs_.end()) ? p->second : NULL;
950 }
951
952 // Look up an arm v4bx relocation stub using the register index.
953 // Return NULL if there is none.
954 Arm_v4bx_stub*
955 find_arm_v4bx_stub(const uint32_t reg) const
956 {
957 gold_assert(reg < 0xf);
958 return this->arm_v4bx_stubs_[reg];
959 }
960
961 // Relocate stubs in this stub table.
962 void
963 relocate_stubs(const Relocate_info<32, big_endian>*,
964 Target_arm<big_endian>*, Output_section*,
965 unsigned char*, Arm_address, section_size_type);
966
967 // Update data size and alignment at the end of a relaxation pass. Return
968 // true if either data size or alignment is different from that of the
969 // previous relaxation pass.
970 bool
971 update_data_size_and_addralign();
972
973 // Finalize stubs. Set the offsets of all stubs and mark input sections
974 // needing the Cortex-A8 workaround.
975 void
976 finalize_stubs();
977
978 // Apply Cortex-A8 workaround to an address range.
979 void
980 apply_cortex_a8_workaround_to_address_range(Target_arm<big_endian>*,
981 unsigned char*, Arm_address,
982 section_size_type);
983
984 protected:
985 // Write out section contents.
986 void
987 do_write(Output_file*);
988
989 // Return the required alignment.
990 uint64_t
991 do_addralign() const
992 { return this->prev_addralign_; }
993
994 // Reset address and file offset.
995 void
996 do_reset_address_and_file_offset()
997 { this->set_current_data_size_for_child(this->prev_data_size_); }
998
999 // Set final data size.
1000 void
1001 set_final_data_size()
1002 { this->set_data_size(this->current_data_size()); }
1003
1004 private:
1005 // Relocate one stub.
1006 void
1007 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
1008 Target_arm<big_endian>*, Output_section*,
1009 unsigned char*, Arm_address, section_size_type);
1010
1011 // Unordered map of relocation stubs.
1012 typedef
1013 Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
1014 Reloc_stub::Key::equal_to>
1015 Reloc_stub_map;
1016
1017 // List of Cortex-A8 stubs ordered by addresses of branches being
1018 // fixed up in output.
1019 typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list;
1020 // List of Arm V4BX relocation stubs ordered by associated registers.
1021 typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list;
1022
1023 // Owner of this stub table.
1024 Arm_input_section<big_endian>* owner_;
1025 // The relocation stubs.
1026 Reloc_stub_map reloc_stubs_;
1027 // Size of reloc stubs.
1028 off_t reloc_stubs_size_;
1029 // Maximum address alignment of reloc stubs.
1030 uint64_t reloc_stubs_addralign_;
1031 // The cortex_a8_stubs.
1032 Cortex_a8_stub_list cortex_a8_stubs_;
1033 // The Arm V4BX relocation stubs.
1034 Arm_v4bx_stub_list arm_v4bx_stubs_;
1035 // data size of this in the previous pass.
1036 off_t prev_data_size_;
1037 // address alignment of this in the previous pass.
1038 uint64_t prev_addralign_;
1039 };
1040
1041 // Arm_exidx_cantunwind class. This represents an EXIDX_CANTUNWIND entry
1042 // we add to the end of an EXIDX input section that goes into the output.
1043
1044 class Arm_exidx_cantunwind : public Output_section_data
1045 {
1046 public:
1047 Arm_exidx_cantunwind(Relobj* relobj, unsigned int shndx)
1048 : Output_section_data(8, 4, true), relobj_(relobj), shndx_(shndx)
1049 { }
1050
1051 // Return the object containing the section pointed by this.
1052 Relobj*
1053 relobj() const
1054 { return this->relobj_; }
1055
1056 // Return the section index of the section pointed by this.
1057 unsigned int
1058 shndx() const
1059 { return this->shndx_; }
1060
1061 protected:
1062 void
1063 do_write(Output_file* of)
1064 {
1065 if (parameters->target().is_big_endian())
1066 this->do_fixed_endian_write<true>(of);
1067 else
1068 this->do_fixed_endian_write<false>(of);
1069 }
1070
1071 // Write to a map file.
1072 void
1073 do_print_to_mapfile(Mapfile* mapfile) const
1074 { mapfile->print_output_data(this, _("** ARM cantunwind")); }
1075
1076 private:
1077 // Implement do_write for a given endianness.
1078 template<bool big_endian>
1079 void inline
1080 do_fixed_endian_write(Output_file*);
1081
1082 // The object containing the section pointed by this.
1083 Relobj* relobj_;
1084 // The section index of the section pointed by this.
1085 unsigned int shndx_;
1086 };
1087
1088 // During EXIDX coverage fix-up, we compact an EXIDX section. The
1089 // Offset map is used to map input section offset within the EXIDX section
1090 // to the output offset from the start of this EXIDX section.
1091
1092 typedef std::map<section_offset_type, section_offset_type>
1093 Arm_exidx_section_offset_map;
1094
1095 // Arm_exidx_merged_section class. This represents an EXIDX input section
1096 // with some of its entries merged.
1097
1098 class Arm_exidx_merged_section : public Output_relaxed_input_section
1099 {
1100 public:
1101 // Constructor for Arm_exidx_merged_section.
1102 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
1103 // SECTION_OFFSET_MAP points to a section offset map describing how
1104 // parts of the input section are mapped to output. DELETED_BYTES is
1105 // the number of bytes deleted from the EXIDX input section.
1106 Arm_exidx_merged_section(
1107 const Arm_exidx_input_section& exidx_input_section,
1108 const Arm_exidx_section_offset_map& section_offset_map,
1109 uint32_t deleted_bytes);
1110
1111 // Build output contents.
1112 void
1113 build_contents(const unsigned char*, section_size_type);
1114
1115 // Return the original EXIDX input section.
1116 const Arm_exidx_input_section&
1117 exidx_input_section() const
1118 { return this->exidx_input_section_; }
1119
1120 // Return the section offset map.
1121 const Arm_exidx_section_offset_map&
1122 section_offset_map() const
1123 { return this->section_offset_map_; }
1124
1125 protected:
1126 // Write merged section into file OF.
1127 void
1128 do_write(Output_file* of);
1129
1130 bool
1131 do_output_offset(const Relobj*, unsigned int, section_offset_type,
1132 section_offset_type*) const;
1133
1134 private:
1135 // Original EXIDX input section.
1136 const Arm_exidx_input_section& exidx_input_section_;
1137 // Section offset map.
1138 const Arm_exidx_section_offset_map& section_offset_map_;
1139 // Merged section contents. We need to keep build the merged section
1140 // and save it here to avoid accessing the original EXIDX section when
1141 // we cannot lock the sections' object.
1142 unsigned char* section_contents_;
1143 };
1144
1145 // A class to wrap an ordinary input section containing executable code.
1146
1147 template<bool big_endian>
1148 class Arm_input_section : public Output_relaxed_input_section
1149 {
1150 public:
1151 Arm_input_section(Relobj* relobj, unsigned int shndx)
1152 : Output_relaxed_input_section(relobj, shndx, 1),
1153 original_addralign_(1), original_size_(0), stub_table_(NULL),
1154 original_contents_(NULL)
1155 { }
1156
1157 ~Arm_input_section()
1158 { delete[] this->original_contents_; }
1159
1160 // Initialize.
1161 void
1162 init();
1163
1164 // Whether this is a stub table owner.
1165 bool
1166 is_stub_table_owner() const
1167 { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
1168
1169 // Return the stub table.
1170 Stub_table<big_endian>*
1171 stub_table() const
1172 { return this->stub_table_; }
1173
1174 // Set the stub_table.
1175 void
1176 set_stub_table(Stub_table<big_endian>* stub_table)
1177 { this->stub_table_ = stub_table; }
1178
1179 // Downcast a base pointer to an Arm_input_section pointer. This is
1180 // not type-safe but we only use Arm_input_section not the base class.
1181 static Arm_input_section<big_endian>*
1182 as_arm_input_section(Output_relaxed_input_section* poris)
1183 { return static_cast<Arm_input_section<big_endian>*>(poris); }
1184
1185 // Return the original size of the section.
1186 uint32_t
1187 original_size() const
1188 { return this->original_size_; }
1189
1190 protected:
1191 // Write data to output file.
1192 void
1193 do_write(Output_file*);
1194
1195 // Return required alignment of this.
1196 uint64_t
1197 do_addralign() const
1198 {
1199 if (this->is_stub_table_owner())
1200 return std::max(this->stub_table_->addralign(),
1201 static_cast<uint64_t>(this->original_addralign_));
1202 else
1203 return this->original_addralign_;
1204 }
1205
1206 // Finalize data size.
1207 void
1208 set_final_data_size();
1209
1210 // Reset address and file offset.
1211 void
1212 do_reset_address_and_file_offset();
1213
1214 // Output offset.
1215 bool
1216 do_output_offset(const Relobj* object, unsigned int shndx,
1217 section_offset_type offset,
1218 section_offset_type* poutput) const
1219 {
1220 if ((object == this->relobj())
1221 && (shndx == this->shndx())
1222 && (offset >= 0)
1223 && (offset <=
1224 convert_types<section_offset_type, uint32_t>(this->original_size_)))
1225 {
1226 *poutput = offset;
1227 return true;
1228 }
1229 else
1230 return false;
1231 }
1232
1233 private:
1234 // Copying is not allowed.
1235 Arm_input_section(const Arm_input_section&);
1236 Arm_input_section& operator=(const Arm_input_section&);
1237
1238 // Address alignment of the original input section.
1239 uint32_t original_addralign_;
1240 // Section size of the original input section.
1241 uint32_t original_size_;
1242 // Stub table.
1243 Stub_table<big_endian>* stub_table_;
1244 // Original section contents. We have to make a copy here since the file
1245 // containing the original section may not be locked when we need to access
1246 // the contents.
1247 unsigned char* original_contents_;
1248 };
1249
1250 // Arm_exidx_fixup class. This is used to define a number of methods
1251 // and keep states for fixing up EXIDX coverage.
1252
1253 class Arm_exidx_fixup
1254 {
1255 public:
1256 Arm_exidx_fixup(Output_section* exidx_output_section,
1257 bool merge_exidx_entries = true)
1258 : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
1259 last_inlined_entry_(0), last_input_section_(NULL),
1260 section_offset_map_(NULL), first_output_text_section_(NULL),
1261 merge_exidx_entries_(merge_exidx_entries)
1262 { }
1263
1264 ~Arm_exidx_fixup()
1265 { delete this->section_offset_map_; }
1266
1267 // Process an EXIDX section for entry merging. SECTION_CONTENTS points
1268 // to the EXIDX contents and SECTION_SIZE is the size of the contents. Return
1269 // number of bytes to be deleted in output. If parts of the input EXIDX
1270 // section are merged a heap allocated Arm_exidx_section_offset_map is store
1271 // in the located PSECTION_OFFSET_MAP. The caller owns the map and is
1272 // responsible for releasing it.
1273 template<bool big_endian>
1274 uint32_t
1275 process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
1276 const unsigned char* section_contents,
1277 section_size_type section_size,
1278 Arm_exidx_section_offset_map** psection_offset_map);
1279
1280 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1281 // input section, if there is not one already.
1282 void
1283 add_exidx_cantunwind_as_needed();
1284
1285 // Return the output section for the text section which is linked to the
1286 // first exidx input in output.
1287 Output_section*
1288 first_output_text_section() const
1289 { return this->first_output_text_section_; }
1290
1291 private:
1292 // Copying is not allowed.
1293 Arm_exidx_fixup(const Arm_exidx_fixup&);
1294 Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
1295
1296 // Type of EXIDX unwind entry.
1297 enum Unwind_type
1298 {
1299 // No type.
1300 UT_NONE,
1301 // EXIDX_CANTUNWIND.
1302 UT_EXIDX_CANTUNWIND,
1303 // Inlined entry.
1304 UT_INLINED_ENTRY,
1305 // Normal entry.
1306 UT_NORMAL_ENTRY,
1307 };
1308
1309 // Process an EXIDX entry. We only care about the second word of the
1310 // entry. Return true if the entry can be deleted.
1311 bool
1312 process_exidx_entry(uint32_t second_word);
1313
1314 // Update the current section offset map during EXIDX section fix-up.
1315 // If there is no map, create one. INPUT_OFFSET is the offset of a
1316 // reference point, DELETED_BYTES is the number of deleted by in the
1317 // section so far. If DELETE_ENTRY is true, the reference point and
1318 // all offsets after the previous reference point are discarded.
1319 void
1320 update_offset_map(section_offset_type input_offset,
1321 section_size_type deleted_bytes, bool delete_entry);
1322
1323 // EXIDX output section.
1324 Output_section* exidx_output_section_;
1325 // Unwind type of the last EXIDX entry processed.
1326 Unwind_type last_unwind_type_;
1327 // Last seen inlined EXIDX entry.
1328 uint32_t last_inlined_entry_;
1329 // Last processed EXIDX input section.
1330 const Arm_exidx_input_section* last_input_section_;
1331 // Section offset map created in process_exidx_section.
1332 Arm_exidx_section_offset_map* section_offset_map_;
1333 // Output section for the text section which is linked to the first exidx
1334 // input in output.
1335 Output_section* first_output_text_section_;
1336
1337 bool merge_exidx_entries_;
1338 };
1339
1340 // Arm output section class. This is defined mainly to add a number of
1341 // stub generation methods.
1342
1343 template<bool big_endian>
1344 class Arm_output_section : public Output_section
1345 {
1346 public:
1347 typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
1348
1349 // We need to force SHF_LINK_ORDER in a SHT_ARM_EXIDX section.
1350 Arm_output_section(const char* name, elfcpp::Elf_Word type,
1351 elfcpp::Elf_Xword flags)
1352 : Output_section(name, type,
1353 (type == elfcpp::SHT_ARM_EXIDX
1354 ? flags | elfcpp::SHF_LINK_ORDER
1355 : flags))
1356 {
1357 if (type == elfcpp::SHT_ARM_EXIDX)
1358 this->set_always_keeps_input_sections();
1359 }
1360
1361 ~Arm_output_section()
1362 { }
1363
1364 // Group input sections for stub generation.
1365 void
1366 group_sections(section_size_type, bool, Target_arm<big_endian>*, const Task*);
1367
1368 // Downcast a base pointer to an Arm_output_section pointer. This is
1369 // not type-safe but we only use Arm_output_section not the base class.
1370 static Arm_output_section<big_endian>*
1371 as_arm_output_section(Output_section* os)
1372 { return static_cast<Arm_output_section<big_endian>*>(os); }
1373
1374 // Append all input text sections in this into LIST.
1375 void
1376 append_text_sections_to_list(Text_section_list* list);
1377
1378 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1379 // is a list of text input sections sorted in ascending order of their
1380 // output addresses.
1381 void
1382 fix_exidx_coverage(Layout* layout,
1383 const Text_section_list& sorted_text_section,
1384 Symbol_table* symtab,
1385 bool merge_exidx_entries,
1386 const Task* task);
1387
1388 // Link an EXIDX section into its corresponding text section.
1389 void
1390 set_exidx_section_link();
1391
1392 private:
1393 // For convenience.
1394 typedef Output_section::Input_section Input_section;
1395 typedef Output_section::Input_section_list Input_section_list;
1396
1397 // Create a stub group.
1398 void create_stub_group(Input_section_list::const_iterator,
1399 Input_section_list::const_iterator,
1400 Input_section_list::const_iterator,
1401 Target_arm<big_endian>*,
1402 std::vector<Output_relaxed_input_section*>*,
1403 const Task* task);
1404 };
1405
1406 // Arm_exidx_input_section class. This represents an EXIDX input section.
1407
1408 class Arm_exidx_input_section
1409 {
1410 public:
1411 static const section_offset_type invalid_offset =
1412 static_cast<section_offset_type>(-1);
1413
1414 Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
1415 unsigned int link, uint32_t size,
1416 uint32_t addralign, uint32_t text_size)
1417 : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
1418 addralign_(addralign), text_size_(text_size), has_errors_(false)
1419 { }
1420
1421 ~Arm_exidx_input_section()
1422 { }
1423
1424 // Accessors: This is a read-only class.
1425
1426 // Return the object containing this EXIDX input section.
1427 Relobj*
1428 relobj() const
1429 { return this->relobj_; }
1430
1431 // Return the section index of this EXIDX input section.
1432 unsigned int
1433 shndx() const
1434 { return this->shndx_; }
1435
1436 // Return the section index of linked text section in the same object.
1437 unsigned int
1438 link() const
1439 { return this->link_; }
1440
1441 // Return size of the EXIDX input section.
1442 uint32_t
1443 size() const
1444 { return this->size_; }
1445
1446 // Return address alignment of EXIDX input section.
1447 uint32_t
1448 addralign() const
1449 { return this->addralign_; }
1450
1451 // Return size of the associated text input section.
1452 uint32_t
1453 text_size() const
1454 { return this->text_size_; }
1455
1456 // Whether there are any errors in the EXIDX input section.
1457 bool
1458 has_errors() const
1459 { return this->has_errors_; }
1460
1461 // Set has-errors flag.
1462 void
1463 set_has_errors()
1464 { this->has_errors_ = true; }
1465
1466 private:
1467 // Object containing this.
1468 Relobj* relobj_;
1469 // Section index of this.
1470 unsigned int shndx_;
1471 // text section linked to this in the same object.
1472 unsigned int link_;
1473 // Size of this. For ARM 32-bit is sufficient.
1474 uint32_t size_;
1475 // Address alignment of this. For ARM 32-bit is sufficient.
1476 uint32_t addralign_;
1477 // Size of associated text section.
1478 uint32_t text_size_;
1479 // Whether this has any errors.
1480 bool has_errors_;
1481 };
1482
1483 // Arm_relobj class.
1484
1485 template<bool big_endian>
1486 class Arm_relobj : public Sized_relobj_file<32, big_endian>
1487 {
1488 public:
1489 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
1490
1491 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
1492 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
1493 : Sized_relobj_file<32, big_endian>(name, input_file, offset, ehdr),
1494 stub_tables_(), local_symbol_is_thumb_function_(),
1495 attributes_section_data_(NULL), mapping_symbols_info_(),
1496 section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
1497 output_local_symbol_count_needs_update_(false),
1498 merge_flags_and_attributes_(true)
1499 { }
1500
1501 ~Arm_relobj()
1502 { delete this->attributes_section_data_; }
1503
1504 // Return the stub table of the SHNDX-th section if there is one.
1505 Stub_table<big_endian>*
1506 stub_table(unsigned int shndx) const
1507 {
1508 gold_assert(shndx < this->stub_tables_.size());
1509 return this->stub_tables_[shndx];
1510 }
1511
1512 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1513 void
1514 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
1515 {
1516 gold_assert(shndx < this->stub_tables_.size());
1517 this->stub_tables_[shndx] = stub_table;
1518 }
1519
1520 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1521 // index. This is only valid after do_count_local_symbol is called.
1522 bool
1523 local_symbol_is_thumb_function(unsigned int r_sym) const
1524 {
1525 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
1526 return this->local_symbol_is_thumb_function_[r_sym];
1527 }
1528
1529 // Scan all relocation sections for stub generation.
1530 void
1531 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
1532 const Layout*);
1533
1534 // Convert regular input section with index SHNDX to a relaxed section.
1535 void
1536 convert_input_section_to_relaxed_section(unsigned shndx)
1537 {
1538 // The stubs have relocations and we need to process them after writing
1539 // out the stubs. So relocation now must follow section write.
1540 this->set_section_offset(shndx, -1ULL);
1541 this->set_relocs_must_follow_section_writes();
1542 }
1543
1544 // Downcast a base pointer to an Arm_relobj pointer. This is
1545 // not type-safe but we only use Arm_relobj not the base class.
1546 static Arm_relobj<big_endian>*
1547 as_arm_relobj(Relobj* relobj)
1548 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
1549
1550 // Processor-specific flags in ELF file header. This is valid only after
1551 // reading symbols.
1552 elfcpp::Elf_Word
1553 processor_specific_flags() const
1554 { return this->processor_specific_flags_; }
1555
1556 // Attribute section data This is the contents of the .ARM.attribute section
1557 // if there is one.
1558 const Attributes_section_data*
1559 attributes_section_data() const
1560 { return this->attributes_section_data_; }
1561
1562 // Mapping symbol location.
1563 typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
1564
1565 // Functor for STL container.
1566 struct Mapping_symbol_position_less
1567 {
1568 bool
1569 operator()(const Mapping_symbol_position& p1,
1570 const Mapping_symbol_position& p2) const
1571 {
1572 return (p1.first < p2.first
1573 || (p1.first == p2.first && p1.second < p2.second));
1574 }
1575 };
1576
1577 // We only care about the first character of a mapping symbol, so
1578 // we only store that instead of the whole symbol name.
1579 typedef std::map<Mapping_symbol_position, char,
1580 Mapping_symbol_position_less> Mapping_symbols_info;
1581
1582 // Whether a section contains any Cortex-A8 workaround.
1583 bool
1584 section_has_cortex_a8_workaround(unsigned int shndx) const
1585 {
1586 return (this->section_has_cortex_a8_workaround_ != NULL
1587 && (*this->section_has_cortex_a8_workaround_)[shndx]);
1588 }
1589
1590 // Mark a section that has Cortex-A8 workaround.
1591 void
1592 mark_section_for_cortex_a8_workaround(unsigned int shndx)
1593 {
1594 if (this->section_has_cortex_a8_workaround_ == NULL)
1595 this->section_has_cortex_a8_workaround_ =
1596 new std::vector<bool>(this->shnum(), false);
1597 (*this->section_has_cortex_a8_workaround_)[shndx] = true;
1598 }
1599
1600 // Return the EXIDX section of an text section with index SHNDX or NULL
1601 // if the text section has no associated EXIDX section.
1602 const Arm_exidx_input_section*
1603 exidx_input_section_by_link(unsigned int shndx) const
1604 {
1605 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1606 return ((p != this->exidx_section_map_.end()
1607 && p->second->link() == shndx)
1608 ? p->second
1609 : NULL);
1610 }
1611
1612 // Return the EXIDX section with index SHNDX or NULL if there is none.
1613 const Arm_exidx_input_section*
1614 exidx_input_section_by_shndx(unsigned shndx) const
1615 {
1616 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1617 return ((p != this->exidx_section_map_.end()
1618 && p->second->shndx() == shndx)
1619 ? p->second
1620 : NULL);
1621 }
1622
1623 // Whether output local symbol count needs updating.
1624 bool
1625 output_local_symbol_count_needs_update() const
1626 { return this->output_local_symbol_count_needs_update_; }
1627
1628 // Set output_local_symbol_count_needs_update flag to be true.
1629 void
1630 set_output_local_symbol_count_needs_update()
1631 { this->output_local_symbol_count_needs_update_ = true; }
1632
1633 // Update output local symbol count at the end of relaxation.
1634 void
1635 update_output_local_symbol_count();
1636
1637 // Whether we want to merge processor-specific flags and attributes.
1638 bool
1639 merge_flags_and_attributes() const
1640 { return this->merge_flags_and_attributes_; }
1641
1642 // Export list of EXIDX section indices.
1643 void
1644 get_exidx_shndx_list(std::vector<unsigned int>* list) const
1645 {
1646 list->clear();
1647 for (Exidx_section_map::const_iterator p = this->exidx_section_map_.begin();
1648 p != this->exidx_section_map_.end();
1649 ++p)
1650 {
1651 if (p->second->shndx() == p->first)
1652 list->push_back(p->first);
1653 }
1654 // Sort list to make result independent of implementation of map.
1655 std::sort(list->begin(), list->end());
1656 }
1657
1658 protected:
1659 // Post constructor setup.
1660 void
1661 do_setup()
1662 {
1663 // Call parent's setup method.
1664 Sized_relobj_file<32, big_endian>::do_setup();
1665
1666 // Initialize look-up tables.
1667 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
1668 this->stub_tables_.swap(empty_stub_table_list);
1669 }
1670
1671 // Count the local symbols.
1672 void
1673 do_count_local_symbols(Stringpool_template<char>*,
1674 Stringpool_template<char>*);
1675
1676 void
1677 do_relocate_sections(
1678 const Symbol_table* symtab, const Layout* layout,
1679 const unsigned char* pshdrs, Output_file* of,
1680 typename Sized_relobj_file<32, big_endian>::Views* pivews);
1681
1682 // Read the symbol information.
1683 void
1684 do_read_symbols(Read_symbols_data* sd);
1685
1686 // Process relocs for garbage collection.
1687 void
1688 do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
1689
1690 private:
1691
1692 // Whether a section needs to be scanned for relocation stubs.
1693 bool
1694 section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1695 const Relobj::Output_sections&,
1696 const Symbol_table*, const unsigned char*);
1697
1698 // Whether a section is a scannable text section.
1699 bool
1700 section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
1701 const Output_section*, const Symbol_table*);
1702
1703 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1704 bool
1705 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1706 unsigned int, Output_section*,
1707 const Symbol_table*);
1708
1709 // Scan a section for the Cortex-A8 erratum.
1710 void
1711 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
1712 unsigned int, Output_section*,
1713 Target_arm<big_endian>*);
1714
1715 // Find the linked text section of an EXIDX section by looking at the
1716 // first relocation of the EXIDX section. PSHDR points to the section
1717 // headers of a relocation section and PSYMS points to the local symbols.
1718 // PSHNDX points to a location storing the text section index if found.
1719 // Return whether we can find the linked section.
1720 bool
1721 find_linked_text_section(const unsigned char* pshdr,
1722 const unsigned char* psyms, unsigned int* pshndx);
1723
1724 //
1725 // Make a new Arm_exidx_input_section object for EXIDX section with
1726 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1727 // index of the linked text section.
1728 void
1729 make_exidx_input_section(unsigned int shndx,
1730 const elfcpp::Shdr<32, big_endian>& shdr,
1731 unsigned int text_shndx,
1732 const elfcpp::Shdr<32, big_endian>& text_shdr);
1733
1734 // Return the output address of either a plain input section or a
1735 // relaxed input section. SHNDX is the section index.
1736 Arm_address
1737 simple_input_section_output_address(unsigned int, Output_section*);
1738
1739 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
1740 typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
1741 Exidx_section_map;
1742
1743 // List of stub tables.
1744 Stub_table_list stub_tables_;
1745 // Bit vector to tell if a local symbol is a thumb function or not.
1746 // This is only valid after do_count_local_symbol is called.
1747 std::vector<bool> local_symbol_is_thumb_function_;
1748 // processor-specific flags in ELF file header.
1749 elfcpp::Elf_Word processor_specific_flags_;
1750 // Object attributes if there is an .ARM.attributes section or NULL.
1751 Attributes_section_data* attributes_section_data_;
1752 // Mapping symbols information.
1753 Mapping_symbols_info mapping_symbols_info_;
1754 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1755 std::vector<bool>* section_has_cortex_a8_workaround_;
1756 // Map a text section to its associated .ARM.exidx section, if there is one.
1757 Exidx_section_map exidx_section_map_;
1758 // Whether output local symbol count needs updating.
1759 bool output_local_symbol_count_needs_update_;
1760 // Whether we merge processor flags and attributes of this object to
1761 // output.
1762 bool merge_flags_and_attributes_;
1763 };
1764
1765 // Arm_dynobj class.
1766
1767 template<bool big_endian>
1768 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1769 {
1770 public:
1771 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1772 const elfcpp::Ehdr<32, big_endian>& ehdr)
1773 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1774 processor_specific_flags_(0), attributes_section_data_(NULL)
1775 { }
1776
1777 ~Arm_dynobj()
1778 { delete this->attributes_section_data_; }
1779
1780 // Downcast a base pointer to an Arm_relobj pointer. This is
1781 // not type-safe but we only use Arm_relobj not the base class.
1782 static Arm_dynobj<big_endian>*
1783 as_arm_dynobj(Dynobj* dynobj)
1784 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1785
1786 // Processor-specific flags in ELF file header. This is valid only after
1787 // reading symbols.
1788 elfcpp::Elf_Word
1789 processor_specific_flags() const
1790 { return this->processor_specific_flags_; }
1791
1792 // Attributes section data.
1793 const Attributes_section_data*
1794 attributes_section_data() const
1795 { return this->attributes_section_data_; }
1796
1797 protected:
1798 // Read the symbol information.
1799 void
1800 do_read_symbols(Read_symbols_data* sd);
1801
1802 private:
1803 // processor-specific flags in ELF file header.
1804 elfcpp::Elf_Word processor_specific_flags_;
1805 // Object attributes if there is an .ARM.attributes section or NULL.
1806 Attributes_section_data* attributes_section_data_;
1807 };
1808
1809 // Functor to read reloc addends during stub generation.
1810
1811 template<int sh_type, bool big_endian>
1812 struct Stub_addend_reader
1813 {
1814 // Return the addend for a relocation of a particular type. Depending
1815 // on whether this is a REL or RELA relocation, read the addend from a
1816 // view or from a Reloc object.
1817 elfcpp::Elf_types<32>::Elf_Swxword
1818 operator()(
1819 unsigned int /* r_type */,
1820 const unsigned char* /* view */,
1821 const typename Reloc_types<sh_type,
1822 32, big_endian>::Reloc& /* reloc */) const;
1823 };
1824
1825 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1826
1827 template<bool big_endian>
1828 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1829 {
1830 elfcpp::Elf_types<32>::Elf_Swxword
1831 operator()(
1832 unsigned int,
1833 const unsigned char*,
1834 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1835 };
1836
1837 // Specialized Stub_addend_reader for RELA type relocation sections.
1838 // We currently do not handle RELA type relocation sections but it is trivial
1839 // to implement the addend reader. This is provided for completeness and to
1840 // make it easier to add support for RELA relocation sections in the future.
1841
1842 template<bool big_endian>
1843 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1844 {
1845 elfcpp::Elf_types<32>::Elf_Swxword
1846 operator()(
1847 unsigned int,
1848 const unsigned char*,
1849 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1850 big_endian>::Reloc& reloc) const
1851 { return reloc.get_r_addend(); }
1852 };
1853
1854 // Cortex_a8_reloc class. We keep record of relocation that may need
1855 // the Cortex-A8 erratum workaround.
1856
1857 class Cortex_a8_reloc
1858 {
1859 public:
1860 Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
1861 Arm_address destination)
1862 : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
1863 { }
1864
1865 ~Cortex_a8_reloc()
1866 { }
1867
1868 // Accessors: This is a read-only class.
1869
1870 // Return the relocation stub associated with this relocation if there is
1871 // one.
1872 const Reloc_stub*
1873 reloc_stub() const
1874 { return this->reloc_stub_; }
1875
1876 // Return the relocation type.
1877 unsigned int
1878 r_type() const
1879 { return this->r_type_; }
1880
1881 // Return the destination address of the relocation. LSB stores the THUMB
1882 // bit.
1883 Arm_address
1884 destination() const
1885 { return this->destination_; }
1886
1887 private:
1888 // Associated relocation stub if there is one, or NULL.
1889 const Reloc_stub* reloc_stub_;
1890 // Relocation type.
1891 unsigned int r_type_;
1892 // Destination address of this relocation. LSB is used to distinguish
1893 // ARM/THUMB mode.
1894 Arm_address destination_;
1895 };
1896
1897 // Arm_output_data_got class. We derive this from Output_data_got to add
1898 // extra methods to handle TLS relocations in a static link.
1899
1900 template<bool big_endian>
1901 class Arm_output_data_got : public Output_data_got<32, big_endian>
1902 {
1903 public:
1904 Arm_output_data_got(Symbol_table* symtab, Layout* layout)
1905 : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
1906 { }
1907
1908 // Add a static entry for the GOT entry at OFFSET. GSYM is a global
1909 // symbol and R_TYPE is the code of a dynamic relocation that needs to be
1910 // applied in a static link.
1911 void
1912 add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1913 { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
1914
1915 // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
1916 // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
1917 // relocation that needs to be applied in a static link.
1918 void
1919 add_static_reloc(unsigned int got_offset, unsigned int r_type,
1920 Sized_relobj_file<32, big_endian>* relobj,
1921 unsigned int index)
1922 {
1923 this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
1924 index));
1925 }
1926
1927 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
1928 // The first one is initialized to be 1, which is the module index for
1929 // the main executable and the second one 0. A reloc of the type
1930 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
1931 // be applied by gold. GSYM is a global symbol.
1932 void
1933 add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
1934
1935 // Same as the above but for a local symbol in OBJECT with INDEX.
1936 void
1937 add_tls_gd32_with_static_reloc(unsigned int got_type,
1938 Sized_relobj_file<32, big_endian>* object,
1939 unsigned int index);
1940
1941 protected:
1942 // Write out the GOT table.
1943 void
1944 do_write(Output_file*);
1945
1946 private:
1947 // This class represent dynamic relocations that need to be applied by
1948 // gold because we are using TLS relocations in a static link.
1949 class Static_reloc
1950 {
1951 public:
1952 Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1953 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
1954 { this->u_.global.symbol = gsym; }
1955
1956 Static_reloc(unsigned int got_offset, unsigned int r_type,
1957 Sized_relobj_file<32, big_endian>* relobj, unsigned int index)
1958 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
1959 {
1960 this->u_.local.relobj = relobj;
1961 this->u_.local.index = index;
1962 }
1963
1964 // Return the GOT offset.
1965 unsigned int
1966 got_offset() const
1967 { return this->got_offset_; }
1968
1969 // Relocation type.
1970 unsigned int
1971 r_type() const
1972 { return this->r_type_; }
1973
1974 // Whether the symbol is global or not.
1975 bool
1976 symbol_is_global() const
1977 { return this->symbol_is_global_; }
1978
1979 // For a relocation against a global symbol, the global symbol.
1980 Symbol*
1981 symbol() const
1982 {
1983 gold_assert(this->symbol_is_global_);
1984 return this->u_.global.symbol;
1985 }
1986
1987 // For a relocation against a local symbol, the defining object.
1988 Sized_relobj_file<32, big_endian>*
1989 relobj() const
1990 {
1991 gold_assert(!this->symbol_is_global_);
1992 return this->u_.local.relobj;
1993 }
1994
1995 // For a relocation against a local symbol, the local symbol index.
1996 unsigned int
1997 index() const
1998 {
1999 gold_assert(!this->symbol_is_global_);
2000 return this->u_.local.index;
2001 }
2002
2003 private:
2004 // GOT offset of the entry to which this relocation is applied.
2005 unsigned int got_offset_;
2006 // Type of relocation.
2007 unsigned int r_type_;
2008 // Whether this relocation is against a global symbol.
2009 bool symbol_is_global_;
2010 // A global or local symbol.
2011 union
2012 {
2013 struct
2014 {
2015 // For a global symbol, the symbol itself.
2016 Symbol* symbol;
2017 } global;
2018 struct
2019 {
2020 // For a local symbol, the object defining object.
2021 Sized_relobj_file<32, big_endian>* relobj;
2022 // For a local symbol, the symbol index.
2023 unsigned int index;
2024 } local;
2025 } u_;
2026 };
2027
2028 // Symbol table of the output object.
2029 Symbol_table* symbol_table_;
2030 // Layout of the output object.
2031 Layout* layout_;
2032 // Static relocs to be applied to the GOT.
2033 std::vector<Static_reloc> static_relocs_;
2034 };
2035
2036 // The ARM target has many relocation types with odd-sizes or noncontiguous
2037 // bits. The default handling of relocatable relocation cannot process these
2038 // relocations. So we have to extend the default code.
2039
2040 template<bool big_endian, int sh_type, typename Classify_reloc>
2041 class Arm_scan_relocatable_relocs :
2042 public Default_scan_relocatable_relocs<sh_type, Classify_reloc>
2043 {
2044 public:
2045 // Return the strategy to use for a local symbol which is a section
2046 // symbol, given the relocation type.
2047 inline Relocatable_relocs::Reloc_strategy
2048 local_section_strategy(unsigned int r_type, Relobj*)
2049 {
2050 if (sh_type == elfcpp::SHT_RELA)
2051 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
2052 else
2053 {
2054 if (r_type == elfcpp::R_ARM_TARGET1
2055 || r_type == elfcpp::R_ARM_TARGET2)
2056 {
2057 const Target_arm<big_endian>* arm_target =
2058 Target_arm<big_endian>::default_target();
2059 r_type = arm_target->get_real_reloc_type(r_type);
2060 }
2061
2062 switch(r_type)
2063 {
2064 // Relocations that write nothing. These exclude R_ARM_TARGET1
2065 // and R_ARM_TARGET2.
2066 case elfcpp::R_ARM_NONE:
2067 case elfcpp::R_ARM_V4BX:
2068 case elfcpp::R_ARM_TLS_GOTDESC:
2069 case elfcpp::R_ARM_TLS_CALL:
2070 case elfcpp::R_ARM_TLS_DESCSEQ:
2071 case elfcpp::R_ARM_THM_TLS_CALL:
2072 case elfcpp::R_ARM_GOTRELAX:
2073 case elfcpp::R_ARM_GNU_VTENTRY:
2074 case elfcpp::R_ARM_GNU_VTINHERIT:
2075 case elfcpp::R_ARM_THM_TLS_DESCSEQ16:
2076 case elfcpp::R_ARM_THM_TLS_DESCSEQ32:
2077 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
2078 // These should have been converted to something else above.
2079 case elfcpp::R_ARM_TARGET1:
2080 case elfcpp::R_ARM_TARGET2:
2081 gold_unreachable();
2082 // Relocations that write full 32 bits and
2083 // have alignment of 1.
2084 case elfcpp::R_ARM_ABS32:
2085 case elfcpp::R_ARM_REL32:
2086 case elfcpp::R_ARM_SBREL32:
2087 case elfcpp::R_ARM_GOTOFF32:
2088 case elfcpp::R_ARM_BASE_PREL:
2089 case elfcpp::R_ARM_GOT_BREL:
2090 case elfcpp::R_ARM_BASE_ABS:
2091 case elfcpp::R_ARM_ABS32_NOI:
2092 case elfcpp::R_ARM_REL32_NOI:
2093 case elfcpp::R_ARM_PLT32_ABS:
2094 case elfcpp::R_ARM_GOT_ABS:
2095 case elfcpp::R_ARM_GOT_PREL:
2096 case elfcpp::R_ARM_TLS_GD32:
2097 case elfcpp::R_ARM_TLS_LDM32:
2098 case elfcpp::R_ARM_TLS_LDO32:
2099 case elfcpp::R_ARM_TLS_IE32:
2100 case elfcpp::R_ARM_TLS_LE32:
2101 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED;
2102 default:
2103 // For all other static relocations, return RELOC_SPECIAL.
2104 return Relocatable_relocs::RELOC_SPECIAL;
2105 }
2106 }
2107 }
2108 };
2109
2110 template<bool big_endian>
2111 class Target_arm : public Sized_target<32, big_endian>
2112 {
2113 public:
2114 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
2115 Reloc_section;
2116
2117 // When were are relocating a stub, we pass this as the relocation number.
2118 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
2119
2120 Target_arm(const Target::Target_info* info = &arm_info)
2121 : Sized_target<32, big_endian>(info),
2122 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
2123 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
2124 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
2125 stub_tables_(), stub_factory_(Stub_factory::get_instance()),
2126 should_force_pic_veneer_(false),
2127 arm_input_section_map_(), attributes_section_data_(NULL),
2128 fix_cortex_a8_(false), cortex_a8_relocs_info_()
2129 { }
2130
2131 // Whether we force PCI branch veneers.
2132 bool
2133 should_force_pic_veneer() const
2134 { return this->should_force_pic_veneer_; }
2135
2136 // Set PIC veneer flag.
2137 void
2138 set_should_force_pic_veneer(bool value)
2139 { this->should_force_pic_veneer_ = value; }
2140
2141 // Whether we use THUMB-2 instructions.
2142 bool
2143 using_thumb2() const
2144 {
2145 Object_attribute* attr =
2146 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2147 int arch = attr->int_value();
2148 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
2149 }
2150
2151 // Whether we use THUMB/THUMB-2 instructions only.
2152 bool
2153 using_thumb_only() const
2154 {
2155 Object_attribute* attr =
2156 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2157
2158 if (attr->int_value() == elfcpp::TAG_CPU_ARCH_V6_M
2159 || attr->int_value() == elfcpp::TAG_CPU_ARCH_V6S_M)
2160 return true;
2161 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2162 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2163 return false;
2164 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2165 return attr->int_value() == 'M';
2166 }
2167
2168 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2169 bool
2170 may_use_arm_nop() const
2171 {
2172 Object_attribute* attr =
2173 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2174 int arch = attr->int_value();
2175 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2176 || arch == elfcpp::TAG_CPU_ARCH_V6K
2177 || arch == elfcpp::TAG_CPU_ARCH_V7
2178 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2179 }
2180
2181 // Whether we have THUMB-2 NOP.W instruction.
2182 bool
2183 may_use_thumb2_nop() const
2184 {
2185 Object_attribute* attr =
2186 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2187 int arch = attr->int_value();
2188 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2189 || arch == elfcpp::TAG_CPU_ARCH_V7
2190 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2191 }
2192
2193 // Whether we have v4T interworking instructions available.
2194 bool
2195 may_use_v4t_interworking() const
2196 {
2197 Object_attribute* attr =
2198 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2199 int arch = attr->int_value();
2200 return (arch != elfcpp::TAG_CPU_ARCH_PRE_V4
2201 && arch != elfcpp::TAG_CPU_ARCH_V4);
2202 }
2203
2204 // Whether we have v5T interworking instructions available.
2205 bool
2206 may_use_v5t_interworking() const
2207 {
2208 Object_attribute* attr =
2209 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2210 int arch = attr->int_value();
2211 if (parameters->options().fix_arm1176())
2212 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2213 || arch == elfcpp::TAG_CPU_ARCH_V7
2214 || arch == elfcpp::TAG_CPU_ARCH_V6_M
2215 || arch == elfcpp::TAG_CPU_ARCH_V6S_M
2216 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2217 else
2218 return (arch != elfcpp::TAG_CPU_ARCH_PRE_V4
2219 && arch != elfcpp::TAG_CPU_ARCH_V4
2220 && arch != elfcpp::TAG_CPU_ARCH_V4T);
2221 }
2222
2223 // Process the relocations to determine unreferenced sections for
2224 // garbage collection.
2225 void
2226 gc_process_relocs(Symbol_table* symtab,
2227 Layout* layout,
2228 Sized_relobj_file<32, big_endian>* object,
2229 unsigned int data_shndx,
2230 unsigned int sh_type,
2231 const unsigned char* prelocs,
2232 size_t reloc_count,
2233 Output_section* output_section,
2234 bool needs_special_offset_handling,
2235 size_t local_symbol_count,
2236 const unsigned char* plocal_symbols);
2237
2238 // Scan the relocations to look for symbol adjustments.
2239 void
2240 scan_relocs(Symbol_table* symtab,
2241 Layout* layout,
2242 Sized_relobj_file<32, big_endian>* object,
2243 unsigned int data_shndx,
2244 unsigned int sh_type,
2245 const unsigned char* prelocs,
2246 size_t reloc_count,
2247 Output_section* output_section,
2248 bool needs_special_offset_handling,
2249 size_t local_symbol_count,
2250 const unsigned char* plocal_symbols);
2251
2252 // Finalize the sections.
2253 void
2254 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2255
2256 // Return the value to use for a dynamic symbol which requires special
2257 // treatment.
2258 uint64_t
2259 do_dynsym_value(const Symbol*) const;
2260
2261 // Relocate a section.
2262 void
2263 relocate_section(const Relocate_info<32, big_endian>*,
2264 unsigned int sh_type,
2265 const unsigned char* prelocs,
2266 size_t reloc_count,
2267 Output_section* output_section,
2268 bool needs_special_offset_handling,
2269 unsigned char* view,
2270 Arm_address view_address,
2271 section_size_type view_size,
2272 const Reloc_symbol_changes*);
2273
2274 // Scan the relocs during a relocatable link.
2275 void
2276 scan_relocatable_relocs(Symbol_table* symtab,
2277 Layout* layout,
2278 Sized_relobj_file<32, big_endian>* object,
2279 unsigned int data_shndx,
2280 unsigned int sh_type,
2281 const unsigned char* prelocs,
2282 size_t reloc_count,
2283 Output_section* output_section,
2284 bool needs_special_offset_handling,
2285 size_t local_symbol_count,
2286 const unsigned char* plocal_symbols,
2287 Relocatable_relocs*);
2288
2289 // Emit relocations for a section.
2290 void
2291 relocate_relocs(const Relocate_info<32, big_endian>*,
2292 unsigned int sh_type,
2293 const unsigned char* prelocs,
2294 size_t reloc_count,
2295 Output_section* output_section,
2296 off_t offset_in_output_section,
2297 const Relocatable_relocs*,
2298 unsigned char* view,
2299 Arm_address view_address,
2300 section_size_type view_size,
2301 unsigned char* reloc_view,
2302 section_size_type reloc_view_size);
2303
2304 // Perform target-specific processing in a relocatable link. This is
2305 // only used if we use the relocation strategy RELOC_SPECIAL.
2306 void
2307 relocate_special_relocatable(const Relocate_info<32, big_endian>* relinfo,
2308 unsigned int sh_type,
2309 const unsigned char* preloc_in,
2310 size_t relnum,
2311 Output_section* output_section,
2312 off_t offset_in_output_section,
2313 unsigned char* view,
2314 typename elfcpp::Elf_types<32>::Elf_Addr
2315 view_address,
2316 section_size_type view_size,
2317 unsigned char* preloc_out);
2318
2319 // Return whether SYM is defined by the ABI.
2320 bool
2321 do_is_defined_by_abi(const Symbol* sym) const
2322 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2323
2324 // Return whether there is a GOT section.
2325 bool
2326 has_got_section() const
2327 { return this->got_ != NULL; }
2328
2329 // Return the size of the GOT section.
2330 section_size_type
2331 got_size() const
2332 {
2333 gold_assert(this->got_ != NULL);
2334 return this->got_->data_size();
2335 }
2336
2337 // Return the number of entries in the GOT.
2338 unsigned int
2339 got_entry_count() const
2340 {
2341 if (!this->has_got_section())
2342 return 0;
2343 return this->got_size() / 4;
2344 }
2345
2346 // Return the number of entries in the PLT.
2347 unsigned int
2348 plt_entry_count() const;
2349
2350 // Return the offset of the first non-reserved PLT entry.
2351 unsigned int
2352 first_plt_entry_offset() const;
2353
2354 // Return the size of each PLT entry.
2355 unsigned int
2356 plt_entry_size() const;
2357
2358 // Map platform-specific reloc types
2359 static unsigned int
2360 get_real_reloc_type(unsigned int r_type);
2361
2362 //
2363 // Methods to support stub-generations.
2364 //
2365
2366 // Return the stub factory
2367 const Stub_factory&
2368 stub_factory() const
2369 { return this->stub_factory_; }
2370
2371 // Make a new Arm_input_section object.
2372 Arm_input_section<big_endian>*
2373 new_arm_input_section(Relobj*, unsigned int);
2374
2375 // Find the Arm_input_section object corresponding to the SHNDX-th input
2376 // section of RELOBJ.
2377 Arm_input_section<big_endian>*
2378 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2379
2380 // Make a new Stub_table
2381 Stub_table<big_endian>*
2382 new_stub_table(Arm_input_section<big_endian>*);
2383
2384 // Scan a section for stub generation.
2385 void
2386 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2387 const unsigned char*, size_t, Output_section*,
2388 bool, const unsigned char*, Arm_address,
2389 section_size_type);
2390
2391 // Relocate a stub.
2392 void
2393 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2394 Output_section*, unsigned char*, Arm_address,
2395 section_size_type);
2396
2397 // Get the default ARM target.
2398 static Target_arm<big_endian>*
2399 default_target()
2400 {
2401 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2402 && parameters->target().is_big_endian() == big_endian);
2403 return static_cast<Target_arm<big_endian>*>(
2404 parameters->sized_target<32, big_endian>());
2405 }
2406
2407 // Whether NAME belongs to a mapping symbol.
2408 static bool
2409 is_mapping_symbol_name(const char* name)
2410 {
2411 return (name
2412 && name[0] == '$'
2413 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2414 && (name[2] == '\0' || name[2] == '.'));
2415 }
2416
2417 // Whether we work around the Cortex-A8 erratum.
2418 bool
2419 fix_cortex_a8() const
2420 { return this->fix_cortex_a8_; }
2421
2422 // Whether we merge exidx entries in debuginfo.
2423 bool
2424 merge_exidx_entries() const
2425 { return parameters->options().merge_exidx_entries(); }
2426
2427 // Whether we fix R_ARM_V4BX relocation.
2428 // 0 - do not fix
2429 // 1 - replace with MOV instruction (armv4 target)
2430 // 2 - make interworking veneer (>= armv4t targets only)
2431 General_options::Fix_v4bx
2432 fix_v4bx() const
2433 { return parameters->options().fix_v4bx(); }
2434
2435 // Scan a span of THUMB code section for Cortex-A8 erratum.
2436 void
2437 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2438 section_size_type, section_size_type,
2439 const unsigned char*, Arm_address);
2440
2441 // Apply Cortex-A8 workaround to a branch.
2442 void
2443 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2444 unsigned char*, Arm_address);
2445
2446 protected:
2447 // Make the PLT-generator object.
2448 Output_data_plt_arm<big_endian>*
2449 make_data_plt(Layout* layout, Output_data_space* got_plt)
2450 { return this->do_make_data_plt(layout, got_plt); }
2451
2452 // Make an ELF object.
2453 Object*
2454 do_make_elf_object(const std::string&, Input_file*, off_t,
2455 const elfcpp::Ehdr<32, big_endian>& ehdr);
2456
2457 Object*
2458 do_make_elf_object(const std::string&, Input_file*, off_t,
2459 const elfcpp::Ehdr<32, !big_endian>&)
2460 { gold_unreachable(); }
2461
2462 Object*
2463 do_make_elf_object(const std::string&, Input_file*, off_t,
2464 const elfcpp::Ehdr<64, false>&)
2465 { gold_unreachable(); }
2466
2467 Object*
2468 do_make_elf_object(const std::string&, Input_file*, off_t,
2469 const elfcpp::Ehdr<64, true>&)
2470 { gold_unreachable(); }
2471
2472 // Make an output section.
2473 Output_section*
2474 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2475 elfcpp::Elf_Xword flags)
2476 { return new Arm_output_section<big_endian>(name, type, flags); }
2477
2478 void
2479 do_adjust_elf_header(unsigned char* view, int len) const;
2480
2481 // We only need to generate stubs, and hence perform relaxation if we are
2482 // not doing relocatable linking.
2483 bool
2484 do_may_relax() const
2485 { return !parameters->options().relocatable(); }
2486
2487 bool
2488 do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*);
2489
2490 // Determine whether an object attribute tag takes an integer, a
2491 // string or both.
2492 int
2493 do_attribute_arg_type(int tag) const;
2494
2495 // Reorder tags during output.
2496 int
2497 do_attributes_order(int num) const;
2498
2499 // This is called when the target is selected as the default.
2500 void
2501 do_select_as_default_target()
2502 {
2503 // No locking is required since there should only be one default target.
2504 // We cannot have both the big-endian and little-endian ARM targets
2505 // as the default.
2506 gold_assert(arm_reloc_property_table == NULL);
2507 arm_reloc_property_table = new Arm_reloc_property_table();
2508 }
2509
2510 // Virtual function which is set to return true by a target if
2511 // it can use relocation types to determine if a function's
2512 // pointer is taken.
2513 virtual bool
2514 do_can_check_for_function_pointers() const
2515 { return true; }
2516
2517 // Whether a section called SECTION_NAME may have function pointers to
2518 // sections not eligible for safe ICF folding.
2519 virtual bool
2520 do_section_may_have_icf_unsafe_pointers(const char* section_name) const
2521 {
2522 return (!is_prefix_of(".ARM.exidx", section_name)
2523 && !is_prefix_of(".ARM.extab", section_name)
2524 && Target::do_section_may_have_icf_unsafe_pointers(section_name));
2525 }
2526
2527 virtual void
2528 do_define_standard_symbols(Symbol_table*, Layout*);
2529
2530 virtual Output_data_plt_arm<big_endian>*
2531 do_make_data_plt(Layout* layout, Output_data_space* got_plt)
2532 {
2533 return new Output_data_plt_arm_standard<big_endian>(layout, got_plt);
2534 }
2535
2536 private:
2537 // The class which scans relocations.
2538 class Scan
2539 {
2540 public:
2541 Scan()
2542 : issued_non_pic_error_(false)
2543 { }
2544
2545 static inline int
2546 get_reference_flags(unsigned int r_type);
2547
2548 inline void
2549 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2550 Sized_relobj_file<32, big_endian>* object,
2551 unsigned int data_shndx,
2552 Output_section* output_section,
2553 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2554 const elfcpp::Sym<32, big_endian>& lsym,
2555 bool is_discarded);
2556
2557 inline void
2558 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2559 Sized_relobj_file<32, big_endian>* object,
2560 unsigned int data_shndx,
2561 Output_section* output_section,
2562 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2563 Symbol* gsym);
2564
2565 inline bool
2566 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2567 Sized_relobj_file<32, big_endian>* ,
2568 unsigned int ,
2569 Output_section* ,
2570 const elfcpp::Rel<32, big_endian>& ,
2571 unsigned int ,
2572 const elfcpp::Sym<32, big_endian>&);
2573
2574 inline bool
2575 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2576 Sized_relobj_file<32, big_endian>* ,
2577 unsigned int ,
2578 Output_section* ,
2579 const elfcpp::Rel<32, big_endian>& ,
2580 unsigned int , Symbol*);
2581
2582 private:
2583 static void
2584 unsupported_reloc_local(Sized_relobj_file<32, big_endian>*,
2585 unsigned int r_type);
2586
2587 static void
2588 unsupported_reloc_global(Sized_relobj_file<32, big_endian>*,
2589 unsigned int r_type, Symbol*);
2590
2591 void
2592 check_non_pic(Relobj*, unsigned int r_type);
2593
2594 // Almost identical to Symbol::needs_plt_entry except that it also
2595 // handles STT_ARM_TFUNC.
2596 static bool
2597 symbol_needs_plt_entry(const Symbol* sym)
2598 {
2599 // An undefined symbol from an executable does not need a PLT entry.
2600 if (sym->is_undefined() && !parameters->options().shared())
2601 return false;
2602
2603 return (!parameters->doing_static_link()
2604 && (sym->type() == elfcpp::STT_FUNC
2605 || sym->type() == elfcpp::STT_ARM_TFUNC)
2606 && (sym->is_from_dynobj()
2607 || sym->is_undefined()
2608 || sym->is_preemptible()));
2609 }
2610
2611 inline bool
2612 possible_function_pointer_reloc(unsigned int r_type);
2613
2614 // Whether we have issued an error about a non-PIC compilation.
2615 bool issued_non_pic_error_;
2616 };
2617
2618 // The class which implements relocation.
2619 class Relocate
2620 {
2621 public:
2622 Relocate()
2623 { }
2624
2625 ~Relocate()
2626 { }
2627
2628 // Return whether the static relocation needs to be applied.
2629 inline bool
2630 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2631 unsigned int r_type,
2632 bool is_32bit,
2633 Output_section* output_section);
2634
2635 // Do a relocation. Return false if the caller should not issue
2636 // any warnings about this relocation.
2637 inline bool
2638 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2639 Output_section*, size_t relnum,
2640 const elfcpp::Rel<32, big_endian>&,
2641 unsigned int r_type, const Sized_symbol<32>*,
2642 const Symbol_value<32>*,
2643 unsigned char*, Arm_address,
2644 section_size_type);
2645
2646 // Return whether we want to pass flag NON_PIC_REF for this
2647 // reloc. This means the relocation type accesses a symbol not via
2648 // GOT or PLT.
2649 static inline bool
2650 reloc_is_non_pic(unsigned int r_type)
2651 {
2652 switch (r_type)
2653 {
2654 // These relocation types reference GOT or PLT entries explicitly.
2655 case elfcpp::R_ARM_GOT_BREL:
2656 case elfcpp::R_ARM_GOT_ABS:
2657 case elfcpp::R_ARM_GOT_PREL:
2658 case elfcpp::R_ARM_GOT_BREL12:
2659 case elfcpp::R_ARM_PLT32_ABS:
2660 case elfcpp::R_ARM_TLS_GD32:
2661 case elfcpp::R_ARM_TLS_LDM32:
2662 case elfcpp::R_ARM_TLS_IE32:
2663 case elfcpp::R_ARM_TLS_IE12GP:
2664
2665 // These relocate types may use PLT entries.
2666 case elfcpp::R_ARM_CALL:
2667 case elfcpp::R_ARM_THM_CALL:
2668 case elfcpp::R_ARM_JUMP24:
2669 case elfcpp::R_ARM_THM_JUMP24:
2670 case elfcpp::R_ARM_THM_JUMP19:
2671 case elfcpp::R_ARM_PLT32:
2672 case elfcpp::R_ARM_THM_XPC22:
2673 case elfcpp::R_ARM_PREL31:
2674 case elfcpp::R_ARM_SBREL31:
2675 return false;
2676
2677 default:
2678 return true;
2679 }
2680 }
2681
2682 private:
2683 // Do a TLS relocation.
2684 inline typename Arm_relocate_functions<big_endian>::Status
2685 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2686 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2687 const Sized_symbol<32>*, const Symbol_value<32>*,
2688 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2689 section_size_type);
2690
2691 };
2692
2693 // A class which returns the size required for a relocation type,
2694 // used while scanning relocs during a relocatable link.
2695 class Relocatable_size_for_reloc
2696 {
2697 public:
2698 unsigned int
2699 get_size_for_reloc(unsigned int, Relobj*);
2700 };
2701
2702 // Adjust TLS relocation type based on the options and whether this
2703 // is a local symbol.
2704 static tls::Tls_optimization
2705 optimize_tls_reloc(bool is_final, int r_type);
2706
2707 // Get the GOT section, creating it if necessary.
2708 Arm_output_data_got<big_endian>*
2709 got_section(Symbol_table*, Layout*);
2710
2711 // Get the GOT PLT section.
2712 Output_data_space*
2713 got_plt_section() const
2714 {
2715 gold_assert(this->got_plt_ != NULL);
2716 return this->got_plt_;
2717 }
2718
2719 // Create a PLT entry for a global symbol.
2720 void
2721 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2722
2723 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2724 void
2725 define_tls_base_symbol(Symbol_table*, Layout*);
2726
2727 // Create a GOT entry for the TLS module index.
2728 unsigned int
2729 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2730 Sized_relobj_file<32, big_endian>* object);
2731
2732 // Get the PLT section.
2733 const Output_data_plt_arm<big_endian>*
2734 plt_section() const
2735 {
2736 gold_assert(this->plt_ != NULL);
2737 return this->plt_;
2738 }
2739
2740 // Get the dynamic reloc section, creating it if necessary.
2741 Reloc_section*
2742 rel_dyn_section(Layout*);
2743
2744 // Get the section to use for TLS_DESC relocations.
2745 Reloc_section*
2746 rel_tls_desc_section(Layout*) const;
2747
2748 // Return true if the symbol may need a COPY relocation.
2749 // References from an executable object to non-function symbols
2750 // defined in a dynamic object may need a COPY relocation.
2751 bool
2752 may_need_copy_reloc(Symbol* gsym)
2753 {
2754 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2755 && gsym->may_need_copy_reloc());
2756 }
2757
2758 // Add a potential copy relocation.
2759 void
2760 copy_reloc(Symbol_table* symtab, Layout* layout,
2761 Sized_relobj_file<32, big_endian>* object,
2762 unsigned int shndx, Output_section* output_section,
2763 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2764 {
2765 this->copy_relocs_.copy_reloc(symtab, layout,
2766 symtab->get_sized_symbol<32>(sym),
2767 object, shndx, output_section, reloc,
2768 this->rel_dyn_section(layout));
2769 }
2770
2771 // Whether two EABI versions are compatible.
2772 static bool
2773 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2774
2775 // Merge processor-specific flags from input object and those in the ELF
2776 // header of the output.
2777 void
2778 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2779
2780 // Get the secondary compatible architecture.
2781 static int
2782 get_secondary_compatible_arch(const Attributes_section_data*);
2783
2784 // Set the secondary compatible architecture.
2785 static void
2786 set_secondary_compatible_arch(Attributes_section_data*, int);
2787
2788 static int
2789 tag_cpu_arch_combine(const char*, int, int*, int, int);
2790
2791 // Helper to print AEABI enum tag value.
2792 static std::string
2793 aeabi_enum_name(unsigned int);
2794
2795 // Return string value for TAG_CPU_name.
2796 static std::string
2797 tag_cpu_name_value(unsigned int);
2798
2799 // Merge object attributes from input object and those in the output.
2800 void
2801 merge_object_attributes(const char*, const Attributes_section_data*);
2802
2803 // Helper to get an AEABI object attribute
2804 Object_attribute*
2805 get_aeabi_object_attribute(int tag) const
2806 {
2807 Attributes_section_data* pasd = this->attributes_section_data_;
2808 gold_assert(pasd != NULL);
2809 Object_attribute* attr =
2810 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2811 gold_assert(attr != NULL);
2812 return attr;
2813 }
2814
2815 //
2816 // Methods to support stub-generations.
2817 //
2818
2819 // Group input sections for stub generation.
2820 void
2821 group_sections(Layout*, section_size_type, bool, const Task*);
2822
2823 // Scan a relocation for stub generation.
2824 void
2825 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2826 const Sized_symbol<32>*, unsigned int,
2827 const Symbol_value<32>*,
2828 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2829
2830 // Scan a relocation section for stub.
2831 template<int sh_type>
2832 void
2833 scan_reloc_section_for_stubs(
2834 const Relocate_info<32, big_endian>* relinfo,
2835 const unsigned char* prelocs,
2836 size_t reloc_count,
2837 Output_section* output_section,
2838 bool needs_special_offset_handling,
2839 const unsigned char* view,
2840 elfcpp::Elf_types<32>::Elf_Addr view_address,
2841 section_size_type);
2842
2843 // Fix .ARM.exidx section coverage.
2844 void
2845 fix_exidx_coverage(Layout*, const Input_objects*,
2846 Arm_output_section<big_endian>*, Symbol_table*,
2847 const Task*);
2848
2849 // Functors for STL set.
2850 struct output_section_address_less_than
2851 {
2852 bool
2853 operator()(const Output_section* s1, const Output_section* s2) const
2854 { return s1->address() < s2->address(); }
2855 };
2856
2857 // Information about this specific target which we pass to the
2858 // general Target structure.
2859 static const Target::Target_info arm_info;
2860
2861 // The types of GOT entries needed for this platform.
2862 // These values are exposed to the ABI in an incremental link.
2863 // Do not renumber existing values without changing the version
2864 // number of the .gnu_incremental_inputs section.
2865 enum Got_type
2866 {
2867 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2868 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2869 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2870 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2871 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2872 };
2873
2874 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2875
2876 // Map input section to Arm_input_section.
2877 typedef Unordered_map<Section_id,
2878 Arm_input_section<big_endian>*,
2879 Section_id_hash>
2880 Arm_input_section_map;
2881
2882 // Map output addresses to relocs for Cortex-A8 erratum.
2883 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2884 Cortex_a8_relocs_info;
2885
2886 // The GOT section.
2887 Arm_output_data_got<big_endian>* got_;
2888 // The PLT section.
2889 Output_data_plt_arm<big_endian>* plt_;
2890 // The GOT PLT section.
2891 Output_data_space* got_plt_;
2892 // The dynamic reloc section.
2893 Reloc_section* rel_dyn_;
2894 // Relocs saved to avoid a COPY reloc.
2895 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2896 // Space for variables copied with a COPY reloc.
2897 Output_data_space* dynbss_;
2898 // Offset of the GOT entry for the TLS module index.
2899 unsigned int got_mod_index_offset_;
2900 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2901 bool tls_base_symbol_defined_;
2902 // Vector of Stub_tables created.
2903 Stub_table_list stub_tables_;
2904 // Stub factory.
2905 const Stub_factory &stub_factory_;
2906 // Whether we force PIC branch veneers.
2907 bool should_force_pic_veneer_;
2908 // Map for locating Arm_input_sections.
2909 Arm_input_section_map arm_input_section_map_;
2910 // Attributes section data in output.
2911 Attributes_section_data* attributes_section_data_;
2912 // Whether we want to fix code for Cortex-A8 erratum.
2913 bool fix_cortex_a8_;
2914 // Map addresses to relocs for Cortex-A8 erratum.
2915 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2916 };
2917
2918 template<bool big_endian>
2919 const Target::Target_info Target_arm<big_endian>::arm_info =
2920 {
2921 32, // size
2922 big_endian, // is_big_endian
2923 elfcpp::EM_ARM, // machine_code
2924 false, // has_make_symbol
2925 false, // has_resolve
2926 false, // has_code_fill
2927 true, // is_default_stack_executable
2928 false, // can_icf_inline_merge_sections
2929 '\0', // wrap_char
2930 "/usr/lib/libc.so.1", // dynamic_linker
2931 0x8000, // default_text_segment_address
2932 0x1000, // abi_pagesize (overridable by -z max-page-size)
2933 0x1000, // common_pagesize (overridable by -z common-page-size)
2934 false, // isolate_execinstr
2935 0, // rosegment_gap
2936 elfcpp::SHN_UNDEF, // small_common_shndx
2937 elfcpp::SHN_UNDEF, // large_common_shndx
2938 0, // small_common_section_flags
2939 0, // large_common_section_flags
2940 ".ARM.attributes", // attributes_section
2941 "aeabi" // attributes_vendor
2942 };
2943
2944 // Arm relocate functions class
2945 //
2946
2947 template<bool big_endian>
2948 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2949 {
2950 public:
2951 typedef enum
2952 {
2953 STATUS_OKAY, // No error during relocation.
2954 STATUS_OVERFLOW, // Relocation overflow.
2955 STATUS_BAD_RELOC // Relocation cannot be applied.
2956 } Status;
2957
2958 private:
2959 typedef Relocate_functions<32, big_endian> Base;
2960 typedef Arm_relocate_functions<big_endian> This;
2961
2962 // Encoding of imm16 argument for movt and movw ARM instructions
2963 // from ARM ARM:
2964 //
2965 // imm16 := imm4 | imm12
2966 //
2967 // 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
2968 // +-------+---------------+-------+-------+-----------------------+
2969 // | | |imm4 | |imm12 |
2970 // +-------+---------------+-------+-------+-----------------------+
2971
2972 // Extract the relocation addend from VAL based on the ARM
2973 // instruction encoding described above.
2974 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2975 extract_arm_movw_movt_addend(
2976 typename elfcpp::Swap<32, big_endian>::Valtype val)
2977 {
2978 // According to the Elf ABI for ARM Architecture the immediate
2979 // field is sign-extended to form the addend.
2980 return Bits<16>::sign_extend32(((val >> 4) & 0xf000) | (val & 0xfff));
2981 }
2982
2983 // Insert X into VAL based on the ARM instruction encoding described
2984 // above.
2985 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2986 insert_val_arm_movw_movt(
2987 typename elfcpp::Swap<32, big_endian>::Valtype val,
2988 typename elfcpp::Swap<32, big_endian>::Valtype x)
2989 {
2990 val &= 0xfff0f000;
2991 val |= x & 0x0fff;
2992 val |= (x & 0xf000) << 4;
2993 return val;
2994 }
2995
2996 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2997 // from ARM ARM:
2998 //
2999 // imm16 := imm4 | i | imm3 | imm8
3000 //
3001 // 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
3002 // +---------+-+-----------+-------++-+-----+-------+---------------+
3003 // | |i| |imm4 || |imm3 | |imm8 |
3004 // +---------+-+-----------+-------++-+-----+-------+---------------+
3005
3006 // Extract the relocation addend from VAL based on the Thumb2
3007 // instruction encoding described above.
3008 static inline typename elfcpp::Swap<32, big_endian>::Valtype
3009 extract_thumb_movw_movt_addend(
3010 typename elfcpp::Swap<32, big_endian>::Valtype val)
3011 {
3012 // According to the Elf ABI for ARM Architecture the immediate
3013 // field is sign-extended to form the addend.
3014 return Bits<16>::sign_extend32(((val >> 4) & 0xf000)
3015 | ((val >> 15) & 0x0800)
3016 | ((val >> 4) & 0x0700)
3017 | (val & 0x00ff));
3018 }
3019
3020 // Insert X into VAL based on the Thumb2 instruction encoding
3021 // described above.
3022 static inline typename elfcpp::Swap<32, big_endian>::Valtype
3023 insert_val_thumb_movw_movt(
3024 typename elfcpp::Swap<32, big_endian>::Valtype val,
3025 typename elfcpp::Swap<32, big_endian>::Valtype x)
3026 {
3027 val &= 0xfbf08f00;
3028 val |= (x & 0xf000) << 4;
3029 val |= (x & 0x0800) << 15;
3030 val |= (x & 0x0700) << 4;
3031 val |= (x & 0x00ff);
3032 return val;
3033 }
3034
3035 // Calculate the smallest constant Kn for the specified residual.
3036 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3037 static uint32_t
3038 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
3039 {
3040 int32_t msb;
3041
3042 if (residual == 0)
3043 return 0;
3044 // Determine the most significant bit in the residual and
3045 // align the resulting value to a 2-bit boundary.
3046 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
3047 ;
3048 // The desired shift is now (msb - 6), or zero, whichever
3049 // is the greater.
3050 return (((msb - 6) < 0) ? 0 : (msb - 6));
3051 }
3052
3053 // Calculate the final residual for the specified group index.
3054 // If the passed group index is less than zero, the method will return
3055 // the value of the specified residual without any change.
3056 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3057 static typename elfcpp::Swap<32, big_endian>::Valtype
3058 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3059 const int group)
3060 {
3061 for (int n = 0; n <= group; n++)
3062 {
3063 // Calculate which part of the value to mask.
3064 uint32_t shift = calc_grp_kn(residual);
3065 // Calculate the residual for the next time around.
3066 residual &= ~(residual & (0xff << shift));
3067 }
3068
3069 return residual;
3070 }
3071
3072 // Calculate the value of Gn for the specified group index.
3073 // We return it in the form of an encoded constant-and-rotation.
3074 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3075 static typename elfcpp::Swap<32, big_endian>::Valtype
3076 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3077 const int group)
3078 {
3079 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
3080 uint32_t shift = 0;
3081
3082 for (int n = 0; n <= group; n++)
3083 {
3084 // Calculate which part of the value to mask.
3085 shift = calc_grp_kn(residual);
3086 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
3087 gn = residual & (0xff << shift);
3088 // Calculate the residual for the next time around.
3089 residual &= ~gn;
3090 }
3091 // Return Gn in the form of an encoded constant-and-rotation.
3092 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
3093 }
3094
3095 public:
3096 // Handle ARM long branches.
3097 static typename This::Status
3098 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3099 unsigned char*, const Sized_symbol<32>*,
3100 const Arm_relobj<big_endian>*, unsigned int,
3101 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3102
3103 // Handle THUMB long branches.
3104 static typename This::Status
3105 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3106 unsigned char*, const Sized_symbol<32>*,
3107 const Arm_relobj<big_endian>*, unsigned int,
3108 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3109
3110
3111 // Return the branch offset of a 32-bit THUMB branch.
3112 static inline int32_t
3113 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3114 {
3115 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
3116 // involving the J1 and J2 bits.
3117 uint32_t s = (upper_insn & (1U << 10)) >> 10;
3118 uint32_t upper = upper_insn & 0x3ffU;
3119 uint32_t lower = lower_insn & 0x7ffU;
3120 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
3121 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
3122 uint32_t i1 = j1 ^ s ? 0 : 1;
3123 uint32_t i2 = j2 ^ s ? 0 : 1;
3124
3125 return Bits<25>::sign_extend32((s << 24) | (i1 << 23) | (i2 << 22)
3126 | (upper << 12) | (lower << 1));
3127 }
3128
3129 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
3130 // UPPER_INSN is the original upper instruction of the branch. Caller is
3131 // responsible for overflow checking and BLX offset adjustment.
3132 static inline uint16_t
3133 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
3134 {
3135 uint32_t s = offset < 0 ? 1 : 0;
3136 uint32_t bits = static_cast<uint32_t>(offset);
3137 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
3138 }
3139
3140 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
3141 // LOWER_INSN is the original lower instruction of the branch. Caller is
3142 // responsible for overflow checking and BLX offset adjustment.
3143 static inline uint16_t
3144 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
3145 {
3146 uint32_t s = offset < 0 ? 1 : 0;
3147 uint32_t bits = static_cast<uint32_t>(offset);
3148 return ((lower_insn & ~0x2fffU)
3149 | ((((bits >> 23) & 1) ^ !s) << 13)
3150 | ((((bits >> 22) & 1) ^ !s) << 11)
3151 | ((bits >> 1) & 0x7ffU));
3152 }
3153
3154 // Return the branch offset of a 32-bit THUMB conditional branch.
3155 static inline int32_t
3156 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3157 {
3158 uint32_t s = (upper_insn & 0x0400U) >> 10;
3159 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
3160 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
3161 uint32_t lower = (lower_insn & 0x07ffU);
3162 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
3163
3164 return Bits<21>::sign_extend32((upper << 12) | (lower << 1));
3165 }
3166
3167 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
3168 // instruction. UPPER_INSN is the original upper instruction of the branch.
3169 // Caller is responsible for overflow checking.
3170 static inline uint16_t
3171 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
3172 {
3173 uint32_t s = offset < 0 ? 1 : 0;
3174 uint32_t bits = static_cast<uint32_t>(offset);
3175 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
3176 }
3177
3178 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
3179 // instruction. LOWER_INSN is the original lower instruction of the branch.
3180 // The caller is responsible for overflow checking.
3181 static inline uint16_t
3182 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
3183 {
3184 uint32_t bits = static_cast<uint32_t>(offset);
3185 uint32_t j2 = (bits & 0x00080000U) >> 19;
3186 uint32_t j1 = (bits & 0x00040000U) >> 18;
3187 uint32_t lo = (bits & 0x00000ffeU) >> 1;
3188
3189 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
3190 }
3191
3192 // R_ARM_ABS8: S + A
3193 static inline typename This::Status
3194 abs8(unsigned char* view,
3195 const Sized_relobj_file<32, big_endian>* object,
3196 const Symbol_value<32>* psymval)
3197 {
3198 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
3199 Valtype* wv = reinterpret_cast<Valtype*>(view);
3200 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
3201 int32_t addend = Bits<8>::sign_extend32(val);
3202 Arm_address x = psymval->value(object, addend);
3203 val = Bits<32>::bit_select32(val, x, 0xffU);
3204 elfcpp::Swap<8, big_endian>::writeval(wv, val);
3205
3206 // R_ARM_ABS8 permits signed or unsigned results.
3207 return (Bits<8>::has_signed_unsigned_overflow32(x)
3208 ? This::STATUS_OVERFLOW
3209 : This::STATUS_OKAY);
3210 }
3211
3212 // R_ARM_THM_ABS5: S + A
3213 static inline typename This::Status
3214 thm_abs5(unsigned char* view,
3215 const Sized_relobj_file<32, big_endian>* object,
3216 const Symbol_value<32>* psymval)
3217 {
3218 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3219 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3220 Valtype* wv = reinterpret_cast<Valtype*>(view);
3221 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3222 Reltype addend = (val & 0x7e0U) >> 6;
3223 Reltype x = psymval->value(object, addend);
3224 val = Bits<32>::bit_select32(val, x << 6, 0x7e0U);
3225 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3226 return (Bits<5>::has_overflow32(x)
3227 ? This::STATUS_OVERFLOW
3228 : This::STATUS_OKAY);
3229 }
3230
3231 // R_ARM_ABS12: S + A
3232 static inline typename This::Status
3233 abs12(unsigned char* view,
3234 const Sized_relobj_file<32, big_endian>* object,
3235 const Symbol_value<32>* psymval)
3236 {
3237 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3238 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3239 Valtype* wv = reinterpret_cast<Valtype*>(view);
3240 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3241 Reltype addend = val & 0x0fffU;
3242 Reltype x = psymval->value(object, addend);
3243 val = Bits<32>::bit_select32(val, x, 0x0fffU);
3244 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3245 return (Bits<12>::has_overflow32(x)
3246 ? This::STATUS_OVERFLOW
3247 : This::STATUS_OKAY);
3248 }
3249
3250 // R_ARM_ABS16: S + A
3251 static inline typename This::Status
3252 abs16(unsigned char* view,
3253 const Sized_relobj_file<32, big_endian>* object,
3254 const Symbol_value<32>* psymval)
3255 {
3256 typedef typename elfcpp::Swap_unaligned<16, big_endian>::Valtype Valtype;
3257 Valtype val = elfcpp::Swap_unaligned<16, big_endian>::readval(view);
3258 int32_t addend = Bits<16>::sign_extend32(val);
3259 Arm_address x = psymval->value(object, addend);
3260 val = Bits<32>::bit_select32(val, x, 0xffffU);
3261 elfcpp::Swap_unaligned<16, big_endian>::writeval(view, val);
3262
3263 // R_ARM_ABS16 permits signed or unsigned results.
3264 return (Bits<16>::has_signed_unsigned_overflow32(x)
3265 ? This::STATUS_OVERFLOW
3266 : This::STATUS_OKAY);
3267 }
3268
3269 // R_ARM_ABS32: (S + A) | T
3270 static inline typename This::Status
3271 abs32(unsigned char* view,
3272 const Sized_relobj_file<32, big_endian>* object,
3273 const Symbol_value<32>* psymval,
3274 Arm_address thumb_bit)
3275 {
3276 typedef typename elfcpp::Swap_unaligned<32, big_endian>::Valtype Valtype;
3277 Valtype addend = elfcpp::Swap_unaligned<32, big_endian>::readval(view);
3278 Valtype x = psymval->value(object, addend) | thumb_bit;
3279 elfcpp::Swap_unaligned<32, big_endian>::writeval(view, x);
3280 return This::STATUS_OKAY;
3281 }
3282
3283 // R_ARM_REL32: (S + A) | T - P
3284 static inline typename This::Status
3285 rel32(unsigned char* view,
3286 const Sized_relobj_file<32, big_endian>* object,
3287 const Symbol_value<32>* psymval,
3288 Arm_address address,
3289 Arm_address thumb_bit)
3290 {
3291 typedef typename elfcpp::Swap_unaligned<32, big_endian>::Valtype Valtype;
3292 Valtype addend = elfcpp::Swap_unaligned<32, big_endian>::readval(view);
3293 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3294 elfcpp::Swap_unaligned<32, big_endian>::writeval(view, x);
3295 return This::STATUS_OKAY;
3296 }
3297
3298 // R_ARM_THM_JUMP24: (S + A) | T - P
3299 static typename This::Status
3300 thm_jump19(unsigned char* view, const Arm_relobj<big_endian>* object,
3301 const Symbol_value<32>* psymval, Arm_address address,
3302 Arm_address thumb_bit);
3303
3304 // R_ARM_THM_JUMP6: S + A – P
3305 static inline typename This::Status
3306 thm_jump6(unsigned char* view,
3307 const Sized_relobj_file<32, big_endian>* object,
3308 const Symbol_value<32>* psymval,
3309 Arm_address address)
3310 {
3311 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3312 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3313 Valtype* wv = reinterpret_cast<Valtype*>(view);
3314 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3315 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3316 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3317 Reltype x = (psymval->value(object, addend) - address);
3318 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3319 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3320 // CZB does only forward jumps.
3321 return ((x > 0x007e)
3322 ? This::STATUS_OVERFLOW
3323 : This::STATUS_OKAY);
3324 }
3325
3326 // R_ARM_THM_JUMP8: S + A – P
3327 static inline typename This::Status
3328 thm_jump8(unsigned char* view,
3329 const Sized_relobj_file<32, big_endian>* object,
3330 const Symbol_value<32>* psymval,
3331 Arm_address address)
3332 {
3333 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3334 Valtype* wv = reinterpret_cast<Valtype*>(view);
3335 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3336 int32_t addend = Bits<8>::sign_extend32((val & 0x00ff) << 1);
3337 int32_t x = (psymval->value(object, addend) - address);
3338 elfcpp::Swap<16, big_endian>::writeval(wv, ((val & 0xff00)
3339 | ((x & 0x01fe) >> 1)));
3340 // We do a 9-bit overflow check because x is right-shifted by 1 bit.
3341 return (Bits<9>::has_overflow32(x)
3342 ? This::STATUS_OVERFLOW
3343 : This::STATUS_OKAY);
3344 }
3345
3346 // R_ARM_THM_JUMP11: S + A – P
3347 static inline typename This::Status
3348 thm_jump11(unsigned char* view,
3349 const Sized_relobj_file<32, big_endian>* object,
3350 const Symbol_value<32>* psymval,
3351 Arm_address address)
3352 {
3353 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3354 Valtype* wv = reinterpret_cast<Valtype*>(view);
3355 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3356 int32_t addend = Bits<11>::sign_extend32((val & 0x07ff) << 1);
3357 int32_t x = (psymval->value(object, addend) - address);
3358 elfcpp::Swap<16, big_endian>::writeval(wv, ((val & 0xf800)
3359 | ((x & 0x0ffe) >> 1)));
3360 // We do a 12-bit overflow check because x is right-shifted by 1 bit.
3361 return (Bits<12>::has_overflow32(x)
3362 ? This::STATUS_OVERFLOW
3363 : This::STATUS_OKAY);
3364 }
3365
3366 // R_ARM_BASE_PREL: B(S) + A - P
3367 static inline typename This::Status
3368 base_prel(unsigned char* view,
3369 Arm_address origin,
3370 Arm_address address)
3371 {
3372 Base::rel32(view, origin - address);
3373 return STATUS_OKAY;
3374 }
3375
3376 // R_ARM_BASE_ABS: B(S) + A
3377 static inline typename This::Status
3378 base_abs(unsigned char* view,
3379 Arm_address origin)
3380 {
3381 Base::rel32(view, origin);
3382 return STATUS_OKAY;
3383 }
3384
3385 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3386 static inline typename This::Status
3387 got_brel(unsigned char* view,
3388 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3389 {
3390 Base::rel32(view, got_offset);
3391 return This::STATUS_OKAY;
3392 }
3393
3394 // R_ARM_GOT_PREL: GOT(S) + A - P
3395 static inline typename This::Status
3396 got_prel(unsigned char* view,
3397 Arm_address got_entry,
3398 Arm_address address)
3399 {
3400 Base::rel32(view, got_entry - address);
3401 return This::STATUS_OKAY;
3402 }
3403
3404 // R_ARM_PREL: (S + A) | T - P
3405 static inline typename This::Status
3406 prel31(unsigned char* view,
3407 const Sized_relobj_file<32, big_endian>* object,
3408 const Symbol_value<32>* psymval,
3409 Arm_address address,
3410 Arm_address thumb_bit)
3411 {
3412 typedef typename elfcpp::Swap_unaligned<32, big_endian>::Valtype Valtype;
3413 Valtype val = elfcpp::Swap_unaligned<32, big_endian>::readval(view);
3414 Valtype addend = Bits<31>::sign_extend32(val);
3415 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3416 val = Bits<32>::bit_select32(val, x, 0x7fffffffU);
3417 elfcpp::Swap_unaligned<32, big_endian>::writeval(view, val);
3418 return (Bits<31>::has_overflow32(x)
3419 ? This::STATUS_OVERFLOW
3420 : This::STATUS_OKAY);
3421 }
3422
3423 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3424 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3425 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3426 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3427 static inline typename This::Status
3428 movw(unsigned char* view,
3429 const Sized_relobj_file<32, big_endian>* object,
3430 const Symbol_value<32>* psymval,
3431 Arm_address relative_address_base,
3432 Arm_address thumb_bit,
3433 bool check_overflow)
3434 {
3435 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3436 Valtype* wv = reinterpret_cast<Valtype*>(view);
3437 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3438 Valtype addend = This::extract_arm_movw_movt_addend(val);
3439 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3440 - relative_address_base);
3441 val = This::insert_val_arm_movw_movt(val, x);
3442 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3443 return ((check_overflow && Bits<16>::has_overflow32(x))
3444 ? This::STATUS_OVERFLOW
3445 : This::STATUS_OKAY);
3446 }
3447
3448 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3449 // R_ARM_MOVT_PREL: S + A - P
3450 // R_ARM_MOVT_BREL: S + A - B(S)
3451 static inline typename This::Status
3452 movt(unsigned char* view,
3453 const Sized_relobj_file<32, big_endian>* object,
3454 const Symbol_value<32>* psymval,
3455 Arm_address relative_address_base)
3456 {
3457 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3458 Valtype* wv = reinterpret_cast<Valtype*>(view);
3459 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3460 Valtype addend = This::extract_arm_movw_movt_addend(val);
3461 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3462 val = This::insert_val_arm_movw_movt(val, x);
3463 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3464 // FIXME: IHI0044D says that we should check for overflow.
3465 return This::STATUS_OKAY;
3466 }
3467
3468 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3469 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3470 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3471 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3472 static inline typename This::Status
3473 thm_movw(unsigned char* view,
3474 const Sized_relobj_file<32, big_endian>* object,
3475 const Symbol_value<32>* psymval,
3476 Arm_address relative_address_base,
3477 Arm_address thumb_bit,
3478 bool check_overflow)
3479 {
3480 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3481 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3482 Valtype* wv = reinterpret_cast<Valtype*>(view);
3483 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3484 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3485 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3486 Reltype x =
3487 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3488 val = This::insert_val_thumb_movw_movt(val, x);
3489 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3490 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3491 return ((check_overflow && Bits<16>::has_overflow32(x))
3492 ? This::STATUS_OVERFLOW
3493 : This::STATUS_OKAY);
3494 }
3495
3496 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3497 // R_ARM_THM_MOVT_PREL: S + A - P
3498 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3499 static inline typename This::Status
3500 thm_movt(unsigned char* view,
3501 const Sized_relobj_file<32, big_endian>* object,
3502 const Symbol_value<32>* psymval,
3503 Arm_address relative_address_base)
3504 {
3505 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3506 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3507 Valtype* wv = reinterpret_cast<Valtype*>(view);
3508 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3509 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3510 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3511 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3512 val = This::insert_val_thumb_movw_movt(val, x);
3513 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3514 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3515 return This::STATUS_OKAY;
3516 }
3517
3518 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3519 static inline typename This::Status
3520 thm_alu11(unsigned char* view,
3521 const Sized_relobj_file<32, big_endian>* object,
3522 const Symbol_value<32>* psymval,
3523 Arm_address address,
3524 Arm_address thumb_bit)
3525 {
3526 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3527 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3528 Valtype* wv = reinterpret_cast<Valtype*>(view);
3529 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3530 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3531
3532 // 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
3533 // -----------------------------------------------------------------------
3534 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3535 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3536 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3537 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3538 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3539 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3540
3541 // Determine a sign for the addend.
3542 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3543 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3544 // Thumb2 addend encoding:
3545 // imm12 := i | imm3 | imm8
3546 int32_t addend = (insn & 0xff)
3547 | ((insn & 0x00007000) >> 4)
3548 | ((insn & 0x04000000) >> 15);
3549 // Apply a sign to the added.
3550 addend *= sign;
3551
3552 int32_t x = (psymval->value(object, addend) | thumb_bit)
3553 - (address & 0xfffffffc);
3554 Reltype val = abs(x);
3555 // Mask out the value and a distinct part of the ADD/SUB opcode
3556 // (bits 7:5 of opword).
3557 insn = (insn & 0xfb0f8f00)
3558 | (val & 0xff)
3559 | ((val & 0x700) << 4)
3560 | ((val & 0x800) << 15);
3561 // Set the opcode according to whether the value to go in the
3562 // place is negative.
3563 if (x < 0)
3564 insn |= 0x00a00000;
3565
3566 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3567 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3568 return ((val > 0xfff) ?
3569 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3570 }
3571
3572 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3573 static inline typename This::Status
3574 thm_pc8(unsigned char* view,
3575 const Sized_relobj_file<32, big_endian>* object,
3576 const Symbol_value<32>* psymval,
3577 Arm_address address)
3578 {
3579 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3580 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3581 Valtype* wv = reinterpret_cast<Valtype*>(view);
3582 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3583 Reltype addend = ((insn & 0x00ff) << 2);
3584 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3585 Reltype val = abs(x);
3586 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3587
3588 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3589 return ((val > 0x03fc)
3590 ? This::STATUS_OVERFLOW
3591 : This::STATUS_OKAY);
3592 }
3593
3594 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3595 static inline typename This::Status
3596 thm_pc12(unsigned char* view,
3597 const Sized_relobj_file<32, big_endian>* object,
3598 const Symbol_value<32>* psymval,
3599 Arm_address address)
3600 {
3601 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3602 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3603 Valtype* wv = reinterpret_cast<Valtype*>(view);
3604 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3605 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3606 // Determine a sign for the addend (positive if the U bit is 1).
3607 const int sign = (insn & 0x00800000) ? 1 : -1;
3608 int32_t addend = (insn & 0xfff);
3609 // Apply a sign to the added.
3610 addend *= sign;
3611
3612 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3613 Reltype val = abs(x);
3614 // Mask out and apply the value and the U bit.
3615 insn = (insn & 0xff7ff000) | (val & 0xfff);
3616 // Set the U bit according to whether the value to go in the
3617 // place is positive.
3618 if (x >= 0)
3619 insn |= 0x00800000;
3620
3621 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3622 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3623 return ((val > 0xfff) ?
3624 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3625 }
3626
3627 // R_ARM_V4BX
3628 static inline typename This::Status
3629 v4bx(const Relocate_info<32, big_endian>* relinfo,
3630 unsigned char* view,
3631 const Arm_relobj<big_endian>* object,
3632 const Arm_address address,
3633 const bool is_interworking)
3634 {
3635
3636 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3637 Valtype* wv = reinterpret_cast<Valtype*>(view);
3638 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3639
3640 // Ensure that we have a BX instruction.
3641 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3642 const uint32_t reg = (val & 0xf);
3643 if (is_interworking && reg != 0xf)
3644 {
3645 Stub_table<big_endian>* stub_table =
3646 object->stub_table(relinfo->data_shndx);
3647 gold_assert(stub_table != NULL);
3648
3649 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3650 gold_assert(stub != NULL);
3651
3652 int32_t veneer_address =
3653 stub_table->address() + stub->offset() - 8 - address;
3654 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3655 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3656 // Replace with a branch to veneer (B <addr>)
3657 val = (val & 0xf0000000) | 0x0a000000
3658 | ((veneer_address >> 2) & 0x00ffffff);
3659 }
3660 else
3661 {
3662 // Preserve Rm (lowest four bits) and the condition code
3663 // (highest four bits). Other bits encode MOV PC,Rm.
3664 val = (val & 0xf000000f) | 0x01a0f000;
3665 }
3666 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3667 return This::STATUS_OKAY;
3668 }
3669
3670 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3671 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3672 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3673 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3674 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3675 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3676 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3677 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3678 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3679 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3680 static inline typename This::Status
3681 arm_grp_alu(unsigned char* view,
3682 const Sized_relobj_file<32, big_endian>* object,
3683 const Symbol_value<32>* psymval,
3684 const int group,
3685 Arm_address address,
3686 Arm_address thumb_bit,
3687 bool check_overflow)
3688 {
3689 gold_assert(group >= 0 && group < 3);
3690 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3691 Valtype* wv = reinterpret_cast<Valtype*>(view);
3692 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3693
3694 // ALU group relocations are allowed only for the ADD/SUB instructions.
3695 // (0x00800000 - ADD, 0x00400000 - SUB)
3696 const Valtype opcode = insn & 0x01e00000;
3697 if (opcode != 0x00800000 && opcode != 0x00400000)
3698 return This::STATUS_BAD_RELOC;
3699
3700 // Determine a sign for the addend.
3701 const int sign = (opcode == 0x00800000) ? 1 : -1;
3702 // shifter = rotate_imm * 2
3703 const uint32_t shifter = (insn & 0xf00) >> 7;
3704 // Initial addend value.
3705 int32_t addend = insn & 0xff;
3706 // Rotate addend right by shifter.
3707 addend = (addend >> shifter) | (addend << (32 - shifter));
3708 // Apply a sign to the added.
3709 addend *= sign;
3710
3711 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3712 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3713 // Check for overflow if required
3714 if (check_overflow
3715 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3716 return This::STATUS_OVERFLOW;
3717
3718 // Mask out the value and the ADD/SUB part of the opcode; take care
3719 // not to destroy the S bit.
3720 insn &= 0xff1ff000;
3721 // Set the opcode according to whether the value to go in the
3722 // place is negative.
3723 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3724 // Encode the offset (encoded Gn).
3725 insn |= gn;
3726
3727 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3728 return This::STATUS_OKAY;
3729 }
3730
3731 // R_ARM_LDR_PC_G0: S + A - P
3732 // R_ARM_LDR_PC_G1: S + A - P
3733 // R_ARM_LDR_PC_G2: S + A - P
3734 // R_ARM_LDR_SB_G0: S + A - B(S)
3735 // R_ARM_LDR_SB_G1: S + A - B(S)
3736 // R_ARM_LDR_SB_G2: S + A - B(S)
3737 static inline typename This::Status
3738 arm_grp_ldr(unsigned char* view,
3739 const Sized_relobj_file<32, big_endian>* object,
3740 const Symbol_value<32>* psymval,
3741 const int group,
3742 Arm_address address)
3743 {
3744 gold_assert(group >= 0 && group < 3);
3745 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3746 Valtype* wv = reinterpret_cast<Valtype*>(view);
3747 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3748
3749 const int sign = (insn & 0x00800000) ? 1 : -1;
3750 int32_t addend = (insn & 0xfff) * sign;
3751 int32_t x = (psymval->value(object, addend) - address);
3752 // Calculate the relevant G(n-1) value to obtain this stage residual.
3753 Valtype residual =
3754 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3755 if (residual >= 0x1000)
3756 return This::STATUS_OVERFLOW;
3757
3758 // Mask out the value and U bit.
3759 insn &= 0xff7ff000;
3760 // Set the U bit for non-negative values.
3761 if (x >= 0)
3762 insn |= 0x00800000;
3763 insn |= residual;
3764
3765 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3766 return This::STATUS_OKAY;
3767 }
3768
3769 // R_ARM_LDRS_PC_G0: S + A - P
3770 // R_ARM_LDRS_PC_G1: S + A - P
3771 // R_ARM_LDRS_PC_G2: S + A - P
3772 // R_ARM_LDRS_SB_G0: S + A - B(S)
3773 // R_ARM_LDRS_SB_G1: S + A - B(S)
3774 // R_ARM_LDRS_SB_G2: S + A - B(S)
3775 static inline typename This::Status
3776 arm_grp_ldrs(unsigned char* view,
3777 const Sized_relobj_file<32, big_endian>* object,
3778 const Symbol_value<32>* psymval,
3779 const int group,
3780 Arm_address address)
3781 {
3782 gold_assert(group >= 0 && group < 3);
3783 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3784 Valtype* wv = reinterpret_cast<Valtype*>(view);
3785 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3786
3787 const int sign = (insn & 0x00800000) ? 1 : -1;
3788 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3789 int32_t x = (psymval->value(object, addend) - address);
3790 // Calculate the relevant G(n-1) value to obtain this stage residual.
3791 Valtype residual =
3792 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3793 if (residual >= 0x100)
3794 return This::STATUS_OVERFLOW;
3795
3796 // Mask out the value and U bit.
3797 insn &= 0xff7ff0f0;
3798 // Set the U bit for non-negative values.
3799 if (x >= 0)
3800 insn |= 0x00800000;
3801 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3802
3803 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3804 return This::STATUS_OKAY;
3805 }
3806
3807 // R_ARM_LDC_PC_G0: S + A - P
3808 // R_ARM_LDC_PC_G1: S + A - P
3809 // R_ARM_LDC_PC_G2: S + A - P
3810 // R_ARM_LDC_SB_G0: S + A - B(S)
3811 // R_ARM_LDC_SB_G1: S + A - B(S)
3812 // R_ARM_LDC_SB_G2: S + A - B(S)
3813 static inline typename This::Status
3814 arm_grp_ldc(unsigned char* view,
3815 const Sized_relobj_file<32, big_endian>* object,
3816 const Symbol_value<32>* psymval,
3817 const int group,
3818 Arm_address address)
3819 {
3820 gold_assert(group >= 0 && group < 3);
3821 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3822 Valtype* wv = reinterpret_cast<Valtype*>(view);
3823 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3824
3825 const int sign = (insn & 0x00800000) ? 1 : -1;
3826 int32_t addend = ((insn & 0xff) << 2) * sign;
3827 int32_t x = (psymval->value(object, addend) - address);
3828 // Calculate the relevant G(n-1) value to obtain this stage residual.
3829 Valtype residual =
3830 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3831 if ((residual & 0x3) != 0 || residual >= 0x400)
3832 return This::STATUS_OVERFLOW;
3833
3834 // Mask out the value and U bit.
3835 insn &= 0xff7fff00;
3836 // Set the U bit for non-negative values.
3837 if (x >= 0)
3838 insn |= 0x00800000;
3839 insn |= (residual >> 2);
3840
3841 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3842 return This::STATUS_OKAY;
3843 }
3844 };
3845
3846 // Relocate ARM long branches. This handles relocation types
3847 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3848 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3849 // undefined and we do not use PLT in this relocation. In such a case,
3850 // the branch is converted into an NOP.
3851
3852 template<bool big_endian>
3853 typename Arm_relocate_functions<big_endian>::Status
3854 Arm_relocate_functions<big_endian>::arm_branch_common(
3855 unsigned int r_type,
3856 const Relocate_info<32, big_endian>* relinfo,
3857 unsigned char* view,
3858 const Sized_symbol<32>* gsym,
3859 const Arm_relobj<big_endian>* object,
3860 unsigned int r_sym,
3861 const Symbol_value<32>* psymval,
3862 Arm_address address,
3863 Arm_address thumb_bit,
3864 bool is_weakly_undefined_without_plt)
3865 {
3866 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3867 Valtype* wv = reinterpret_cast<Valtype*>(view);
3868 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3869
3870 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3871 && ((val & 0x0f000000UL) == 0x0a000000UL);
3872 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3873 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3874 && ((val & 0x0f000000UL) == 0x0b000000UL);
3875 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3876 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3877
3878 // Check that the instruction is valid.
3879 if (r_type == elfcpp::R_ARM_CALL)
3880 {
3881 if (!insn_is_uncond_bl && !insn_is_blx)
3882 return This::STATUS_BAD_RELOC;
3883 }
3884 else if (r_type == elfcpp::R_ARM_JUMP24)
3885 {
3886 if (!insn_is_b && !insn_is_cond_bl)
3887 return This::STATUS_BAD_RELOC;
3888 }
3889 else if (r_type == elfcpp::R_ARM_PLT32)
3890 {
3891 if (!insn_is_any_branch)
3892 return This::STATUS_BAD_RELOC;
3893 }
3894 else if (r_type == elfcpp::R_ARM_XPC25)
3895 {
3896 // FIXME: AAELF document IH0044C does not say much about it other
3897 // than it being obsolete.
3898 if (!insn_is_any_branch)
3899 return This::STATUS_BAD_RELOC;
3900 }
3901 else
3902 gold_unreachable();
3903
3904 // A branch to an undefined weak symbol is turned into a jump to
3905 // the next instruction unless a PLT entry will be created.
3906 // Do the same for local undefined symbols.
3907 // The jump to the next instruction is optimized as a NOP depending
3908 // on the architecture.
3909 const Target_arm<big_endian>* arm_target =
3910 Target_arm<big_endian>::default_target();
3911 if (is_weakly_undefined_without_plt)
3912 {
3913 gold_assert(!parameters->options().relocatable());
3914 Valtype cond = val & 0xf0000000U;
3915 if (arm_target->may_use_arm_nop())
3916 val = cond | 0x0320f000;
3917 else
3918 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3919 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3920 return This::STATUS_OKAY;
3921 }
3922
3923 Valtype addend = Bits<26>::sign_extend32(val << 2);
3924 Valtype branch_target = psymval->value(object, addend);
3925 int32_t branch_offset = branch_target - address;
3926
3927 // We need a stub if the branch offset is too large or if we need
3928 // to switch mode.
3929 bool may_use_blx = arm_target->may_use_v5t_interworking();
3930 Reloc_stub* stub = NULL;
3931
3932 if (!parameters->options().relocatable()
3933 && (Bits<26>::has_overflow32(branch_offset)
3934 || ((thumb_bit != 0)
3935 && !(may_use_blx && r_type == elfcpp::R_ARM_CALL))))
3936 {
3937 Valtype unadjusted_branch_target = psymval->value(object, 0);
3938
3939 Stub_type stub_type =
3940 Reloc_stub::stub_type_for_reloc(r_type, address,
3941 unadjusted_branch_target,
3942 (thumb_bit != 0));
3943 if (stub_type != arm_stub_none)
3944 {
3945 Stub_table<big_endian>* stub_table =
3946 object->stub_table(relinfo->data_shndx);
3947 gold_assert(stub_table != NULL);
3948
3949 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3950 stub = stub_table->find_reloc_stub(stub_key);
3951 gold_assert(stub != NULL);
3952 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3953 branch_target = stub_table->address() + stub->offset() + addend;
3954 branch_offset = branch_target - address;
3955 gold_assert(!Bits<26>::has_overflow32(branch_offset));
3956 }
3957 }
3958
3959 // At this point, if we still need to switch mode, the instruction
3960 // must either be a BLX or a BL that can be converted to a BLX.
3961 if (thumb_bit != 0)
3962 {
3963 // Turn BL to BLX.
3964 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3965 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3966 }
3967
3968 val = Bits<32>::bit_select32(val, (branch_offset >> 2), 0xffffffUL);
3969 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3970 return (Bits<26>::has_overflow32(branch_offset)
3971 ? This::STATUS_OVERFLOW
3972 : This::STATUS_OKAY);
3973 }
3974
3975 // Relocate THUMB long branches. This handles relocation types
3976 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3977 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3978 // undefined and we do not use PLT in this relocation. In such a case,
3979 // the branch is converted into an NOP.
3980
3981 template<bool big_endian>
3982 typename Arm_relocate_functions<big_endian>::Status
3983 Arm_relocate_functions<big_endian>::thumb_branch_common(
3984 unsigned int r_type,
3985 const Relocate_info<32, big_endian>* relinfo,
3986 unsigned char* view,
3987 const Sized_symbol<32>* gsym,
3988 const Arm_relobj<big_endian>* object,
3989 unsigned int r_sym,
3990 const Symbol_value<32>* psymval,
3991 Arm_address address,
3992 Arm_address thumb_bit,
3993 bool is_weakly_undefined_without_plt)
3994 {
3995 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3996 Valtype* wv = reinterpret_cast<Valtype*>(view);
3997 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3998 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3999
4000 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
4001 // into account.
4002 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
4003 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
4004
4005 // Check that the instruction is valid.
4006 if (r_type == elfcpp::R_ARM_THM_CALL)
4007 {
4008 if (!is_bl_insn && !is_blx_insn)
4009 return This::STATUS_BAD_RELOC;
4010 }
4011 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
4012 {
4013 // This cannot be a BLX.
4014 if (!is_bl_insn)
4015 return This::STATUS_BAD_RELOC;
4016 }
4017 else if (r_type == elfcpp::R_ARM_THM_XPC22)
4018 {
4019 // Check for Thumb to Thumb call.
4020 if (!is_blx_insn)
4021 return This::STATUS_BAD_RELOC;
4022 if (thumb_bit != 0)
4023 {
4024 gold_warning(_("%s: Thumb BLX instruction targets "
4025 "thumb function '%s'."),
4026 object->name().c_str(),
4027 (gsym ? gsym->name() : "(local)"));
4028 // Convert BLX to BL.
4029 lower_insn |= 0x1000U;
4030 }
4031 }
4032 else
4033 gold_unreachable();
4034
4035 // A branch to an undefined weak symbol is turned into a jump to
4036 // the next instruction unless a PLT entry will be created.
4037 // The jump to the next instruction is optimized as a NOP.W for
4038 // Thumb-2 enabled architectures.
4039 const Target_arm<big_endian>* arm_target =
4040 Target_arm<big_endian>::default_target();
4041 if (is_weakly_undefined_without_plt)
4042 {
4043 gold_assert(!parameters->options().relocatable());
4044 if (arm_target->may_use_thumb2_nop())
4045 {
4046 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
4047 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
4048 }
4049 else
4050 {
4051 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
4052 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
4053 }
4054 return This::STATUS_OKAY;
4055 }
4056
4057 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
4058 Arm_address branch_target = psymval->value(object, addend);
4059
4060 // For BLX, bit 1 of target address comes from bit 1 of base address.
4061 bool may_use_blx = arm_target->may_use_v5t_interworking();
4062 if (thumb_bit == 0 && may_use_blx)
4063 branch_target = Bits<32>::bit_select32(branch_target, address, 0x2);
4064
4065 int32_t branch_offset = branch_target - address;
4066
4067 // We need a stub if the branch offset is too large or if we need
4068 // to switch mode.
4069 bool thumb2 = arm_target->using_thumb2();
4070 if (!parameters->options().relocatable()
4071 && ((!thumb2 && Bits<23>::has_overflow32(branch_offset))
4072 || (thumb2 && Bits<25>::has_overflow32(branch_offset))
4073 || ((thumb_bit == 0)
4074 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4075 || r_type == elfcpp::R_ARM_THM_JUMP24))))
4076 {
4077 Arm_address unadjusted_branch_target = psymval->value(object, 0);
4078
4079 Stub_type stub_type =
4080 Reloc_stub::stub_type_for_reloc(r_type, address,
4081 unadjusted_branch_target,
4082 (thumb_bit != 0));
4083
4084 if (stub_type != arm_stub_none)
4085 {
4086 Stub_table<big_endian>* stub_table =
4087 object->stub_table(relinfo->data_shndx);
4088 gold_assert(stub_table != NULL);
4089
4090 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
4091 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
4092 gold_assert(stub != NULL);
4093 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
4094 branch_target = stub_table->address() + stub->offset() + addend;
4095 if (thumb_bit == 0 && may_use_blx)
4096 branch_target = Bits<32>::bit_select32(branch_target, address, 0x2);
4097 branch_offset = branch_target - address;
4098 }
4099 }
4100
4101 // At this point, if we still need to switch mode, the instruction
4102 // must either be a BLX or a BL that can be converted to a BLX.
4103 if (thumb_bit == 0)
4104 {
4105 gold_assert(may_use_blx
4106 && (r_type == elfcpp::R_ARM_THM_CALL
4107 || r_type == elfcpp::R_ARM_THM_XPC22));
4108 // Make sure this is a BLX.
4109 lower_insn &= ~0x1000U;
4110 }
4111 else
4112 {
4113 // Make sure this is a BL.
4114 lower_insn |= 0x1000U;
4115 }
4116
4117 // For a BLX instruction, make sure that the relocation is rounded up
4118 // to a word boundary. This follows the semantics of the instruction
4119 // which specifies that bit 1 of the target address will come from bit
4120 // 1 of the base address.
4121 if ((lower_insn & 0x5000U) == 0x4000U)
4122 gold_assert((branch_offset & 3) == 0);
4123
4124 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
4125 // We use the Thumb-2 encoding, which is safe even if dealing with
4126 // a Thumb-1 instruction by virtue of our overflow check above. */
4127 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
4128 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
4129
4130 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4131 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4132
4133 gold_assert(!Bits<25>::has_overflow32(branch_offset));
4134
4135 return ((thumb2
4136 ? Bits<25>::has_overflow32(branch_offset)
4137 : Bits<23>::has_overflow32(branch_offset))
4138 ? This::STATUS_OVERFLOW
4139 : This::STATUS_OKAY);
4140 }
4141
4142 // Relocate THUMB-2 long conditional branches.
4143 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
4144 // undefined and we do not use PLT in this relocation. In such a case,
4145 // the branch is converted into an NOP.
4146
4147 template<bool big_endian>
4148 typename Arm_relocate_functions<big_endian>::Status
4149 Arm_relocate_functions<big_endian>::thm_jump19(
4150 unsigned char* view,
4151 const Arm_relobj<big_endian>* object,
4152 const Symbol_value<32>* psymval,
4153 Arm_address address,
4154 Arm_address thumb_bit)
4155 {
4156 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
4157 Valtype* wv = reinterpret_cast<Valtype*>(view);
4158 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
4159 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
4160 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
4161
4162 Arm_address branch_target = psymval->value(object, addend);
4163 int32_t branch_offset = branch_target - address;
4164
4165 // ??? Should handle interworking? GCC might someday try to
4166 // use this for tail calls.
4167 // FIXME: We do support thumb entry to PLT yet.
4168 if (thumb_bit == 0)
4169 {
4170 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
4171 return This::STATUS_BAD_RELOC;
4172 }
4173
4174 // Put RELOCATION back into the insn.
4175 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
4176 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
4177
4178 // Put the relocated value back in the object file:
4179 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4180 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4181
4182 return (Bits<21>::has_overflow32(branch_offset)
4183 ? This::STATUS_OVERFLOW
4184 : This::STATUS_OKAY);
4185 }
4186
4187 // Get the GOT section, creating it if necessary.
4188
4189 template<bool big_endian>
4190 Arm_output_data_got<big_endian>*
4191 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
4192 {
4193 if (this->got_ == NULL)
4194 {
4195 gold_assert(symtab != NULL && layout != NULL);
4196
4197 // When using -z now, we can treat .got as a relro section.
4198 // Without -z now, it is modified after program startup by lazy
4199 // PLT relocations.
4200 bool is_got_relro = parameters->options().now();
4201 Output_section_order got_order = (is_got_relro
4202 ? ORDER_RELRO_LAST
4203 : ORDER_DATA);
4204
4205 // Unlike some targets (.e.g x86), ARM does not use separate .got and
4206 // .got.plt sections in output. The output .got section contains both
4207 // PLT and non-PLT GOT entries.
4208 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
4209
4210 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4211 (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
4212 this->got_, got_order, is_got_relro);
4213
4214 // The old GNU linker creates a .got.plt section. We just
4215 // create another set of data in the .got section. Note that we
4216 // always create a PLT if we create a GOT, although the PLT
4217 // might be empty.
4218 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
4219 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4220 (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
4221 this->got_plt_, got_order, is_got_relro);
4222
4223 // The first three entries are reserved.
4224 this->got_plt_->set_current_data_size(3 * 4);
4225
4226 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
4227 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
4228 Symbol_table::PREDEFINED,
4229 this->got_plt_,
4230 0, 0, elfcpp::STT_OBJECT,
4231 elfcpp::STB_LOCAL,
4232 elfcpp::STV_HIDDEN, 0,
4233 false, false);
4234 }
4235 return this->got_;
4236 }
4237
4238 // Get the dynamic reloc section, creating it if necessary.
4239
4240 template<bool big_endian>
4241 typename Target_arm<big_endian>::Reloc_section*
4242 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
4243 {
4244 if (this->rel_dyn_ == NULL)
4245 {
4246 gold_assert(layout != NULL);
4247 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
4248 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
4249 elfcpp::SHF_ALLOC, this->rel_dyn_,
4250 ORDER_DYNAMIC_RELOCS, false);
4251 }
4252 return this->rel_dyn_;
4253 }
4254
4255 // Insn_template methods.
4256
4257 // Return byte size of an instruction template.
4258
4259 size_t
4260 Insn_template::size() const
4261 {
4262 switch (this->type())
4263 {
4264 case THUMB16_TYPE:
4265 case THUMB16_SPECIAL_TYPE:
4266 return 2;
4267 case ARM_TYPE:
4268 case THUMB32_TYPE:
4269 case DATA_TYPE:
4270 return 4;
4271 default:
4272 gold_unreachable();
4273 }
4274 }
4275
4276 // Return alignment of an instruction template.
4277
4278 unsigned
4279 Insn_template::alignment() const
4280 {
4281 switch (this->type())
4282 {
4283 case THUMB16_TYPE:
4284 case THUMB16_SPECIAL_TYPE:
4285 case THUMB32_TYPE:
4286 return 2;
4287 case ARM_TYPE:
4288 case DATA_TYPE:
4289 return 4;
4290 default:
4291 gold_unreachable();
4292 }
4293 }
4294
4295 // Stub_template methods.
4296
4297 Stub_template::Stub_template(
4298 Stub_type type, const Insn_template* insns,
4299 size_t insn_count)
4300 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4301 entry_in_thumb_mode_(false), relocs_()
4302 {
4303 off_t offset = 0;
4304
4305 // Compute byte size and alignment of stub template.
4306 for (size_t i = 0; i < insn_count; i++)
4307 {
4308 unsigned insn_alignment = insns[i].alignment();
4309 size_t insn_size = insns[i].size();
4310 gold_assert((offset & (insn_alignment - 1)) == 0);
4311 this->alignment_ = std::max(this->alignment_, insn_alignment);
4312 switch (insns[i].type())
4313 {
4314 case Insn_template::THUMB16_TYPE:
4315 case Insn_template::THUMB16_SPECIAL_TYPE:
4316 if (i == 0)
4317 this->entry_in_thumb_mode_ = true;
4318 break;
4319
4320 case Insn_template::THUMB32_TYPE:
4321 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4322 this->relocs_.push_back(Reloc(i, offset));
4323 if (i == 0)
4324 this->entry_in_thumb_mode_ = true;
4325 break;
4326
4327 case Insn_template::ARM_TYPE:
4328 // Handle cases where the target is encoded within the
4329 // instruction.
4330 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4331 this->relocs_.push_back(Reloc(i, offset));
4332 break;
4333
4334 case Insn_template::DATA_TYPE:
4335 // Entry point cannot be data.
4336 gold_assert(i != 0);
4337 this->relocs_.push_back(Reloc(i, offset));
4338 break;
4339
4340 default:
4341 gold_unreachable();
4342 }
4343 offset += insn_size;
4344 }
4345 this->size_ = offset;
4346 }
4347
4348 // Stub methods.
4349
4350 // Template to implement do_write for a specific target endianness.
4351
4352 template<bool big_endian>
4353 void inline
4354 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4355 {
4356 const Stub_template* stub_template = this->stub_template();
4357 const Insn_template* insns = stub_template->insns();
4358
4359 // FIXME: We do not handle BE8 encoding yet.
4360 unsigned char* pov = view;
4361 for (size_t i = 0; i < stub_template->insn_count(); i++)
4362 {
4363 switch (insns[i].type())
4364 {
4365 case Insn_template::THUMB16_TYPE:
4366 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4367 break;
4368 case Insn_template::THUMB16_SPECIAL_TYPE:
4369 elfcpp::Swap<16, big_endian>::writeval(
4370 pov,
4371 this->thumb16_special(i));
4372 break;
4373 case Insn_template::THUMB32_TYPE:
4374 {
4375 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4376 uint32_t lo = insns[i].data() & 0xffff;
4377 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4378 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4379 }
4380 break;
4381 case Insn_template::ARM_TYPE:
4382 case Insn_template::DATA_TYPE:
4383 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4384 break;
4385 default:
4386 gold_unreachable();
4387 }
4388 pov += insns[i].size();
4389 }
4390 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4391 }
4392
4393 // Reloc_stub::Key methods.
4394
4395 // Dump a Key as a string for debugging.
4396
4397 std::string
4398 Reloc_stub::Key::name() const
4399 {
4400 if (this->r_sym_ == invalid_index)
4401 {
4402 // Global symbol key name
4403 // <stub-type>:<symbol name>:<addend>.
4404 const std::string sym_name = this->u_.symbol->name();
4405 // We need to print two hex number and two colons. So just add 100 bytes
4406 // to the symbol name size.
4407 size_t len = sym_name.size() + 100;
4408 char* buffer = new char[len];
4409 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4410 sym_name.c_str(), this->addend_);
4411 gold_assert(c > 0 && c < static_cast<int>(len));
4412 delete[] buffer;
4413 return std::string(buffer);
4414 }
4415 else
4416 {
4417 // local symbol key name
4418 // <stub-type>:<object>:<r_sym>:<addend>.
4419 const size_t len = 200;
4420 char buffer[len];
4421 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4422 this->u_.relobj, this->r_sym_, this->addend_);
4423 gold_assert(c > 0 && c < static_cast<int>(len));
4424 return std::string(buffer);
4425 }
4426 }
4427
4428 // Reloc_stub methods.
4429
4430 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4431 // LOCATION to DESTINATION.
4432 // This code is based on the arm_type_of_stub function in
4433 // bfd/elf32-arm.c. We have changed the interface a little to keep the Stub
4434 // class simple.
4435
4436 Stub_type
4437 Reloc_stub::stub_type_for_reloc(
4438 unsigned int r_type,
4439 Arm_address location,
4440 Arm_address destination,
4441 bool target_is_thumb)
4442 {
4443 Stub_type stub_type = arm_stub_none;
4444
4445 // This is a bit ugly but we want to avoid using a templated class for
4446 // big and little endianities.
4447 bool may_use_blx;
4448 bool should_force_pic_veneer;
4449 bool thumb2;
4450 bool thumb_only;
4451 if (parameters->target().is_big_endian())
4452 {
4453 const Target_arm<true>* big_endian_target =
4454 Target_arm<true>::default_target();
4455 may_use_blx = big_endian_target->may_use_v5t_interworking();
4456 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4457 thumb2 = big_endian_target->using_thumb2();
4458 thumb_only = big_endian_target->using_thumb_only();
4459 }
4460 else
4461 {
4462 const Target_arm<false>* little_endian_target =
4463 Target_arm<false>::default_target();
4464 may_use_blx = little_endian_target->may_use_v5t_interworking();
4465 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4466 thumb2 = little_endian_target->using_thumb2();
4467 thumb_only = little_endian_target->using_thumb_only();
4468 }
4469
4470 int64_t branch_offset;
4471 bool output_is_position_independent =
4472 parameters->options().output_is_position_independent();
4473 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4474 {
4475 // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
4476 // base address (instruction address + 4).
4477 if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
4478 destination = Bits<32>::bit_select32(destination, location, 0x2);
4479 branch_offset = static_cast<int64_t>(destination) - location;
4480
4481 // Handle cases where:
4482 // - this call goes too far (different Thumb/Thumb2 max
4483 // distance)
4484 // - it's a Thumb->Arm call and blx is not available, or it's a
4485 // Thumb->Arm branch (not bl). A stub is needed in this case.
4486 if ((!thumb2
4487 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4488 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4489 || (thumb2
4490 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4491 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4492 || ((!target_is_thumb)
4493 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4494 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4495 {
4496 if (target_is_thumb)
4497 {
4498 // Thumb to thumb.
4499 if (!thumb_only)
4500 {
4501 stub_type = (output_is_position_independent
4502 || should_force_pic_veneer)
4503 // PIC stubs.
4504 ? ((may_use_blx
4505 && (r_type == elfcpp::R_ARM_THM_CALL))
4506 // V5T and above. Stub starts with ARM code, so
4507 // we must be able to switch mode before
4508 // reaching it, which is only possible for 'bl'
4509 // (ie R_ARM_THM_CALL relocation).
4510 ? arm_stub_long_branch_any_thumb_pic
4511 // On V4T, use Thumb code only.
4512 : arm_stub_long_branch_v4t_thumb_thumb_pic)
4513
4514 // non-PIC stubs.
4515 : ((may_use_blx
4516 && (r_type == elfcpp::R_ARM_THM_CALL))
4517 ? arm_stub_long_branch_any_any // V5T and above.
4518 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
4519 }
4520 else
4521 {
4522 stub_type = (output_is_position_independent
4523 || should_force_pic_veneer)
4524 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4525 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4526 }
4527 }
4528 else
4529 {
4530 // Thumb to arm.
4531
4532 // FIXME: We should check that the input section is from an
4533 // object that has interwork enabled.
4534
4535 stub_type = (output_is_position_independent
4536 || should_force_pic_veneer)
4537 // PIC stubs.
4538 ? ((may_use_blx
4539 && (r_type == elfcpp::R_ARM_THM_CALL))
4540 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4541 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4542
4543 // non-PIC stubs.
4544 : ((may_use_blx
4545 && (r_type == elfcpp::R_ARM_THM_CALL))
4546 ? arm_stub_long_branch_any_any // V5T and above.
4547 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4548
4549 // Handle v4t short branches.
4550 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4551 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4552 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4553 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4554 }
4555 }
4556 }
4557 else if (r_type == elfcpp::R_ARM_CALL
4558 || r_type == elfcpp::R_ARM_JUMP24
4559 || r_type == elfcpp::R_ARM_PLT32)
4560 {
4561 branch_offset = static_cast<int64_t>(destination) - location;
4562 if (target_is_thumb)
4563 {
4564 // Arm to thumb.
4565
4566 // FIXME: We should check that the input section is from an
4567 // object that has interwork enabled.
4568
4569 // We have an extra 2-bytes reach because of
4570 // the mode change (bit 24 (H) of BLX encoding).
4571 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4572 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4573 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4574 || (r_type == elfcpp::R_ARM_JUMP24)
4575 || (r_type == elfcpp::R_ARM_PLT32))
4576 {
4577 stub_type = (output_is_position_independent
4578 || should_force_pic_veneer)
4579 // PIC stubs.
4580 ? (may_use_blx
4581 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4582 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4583
4584 // non-PIC stubs.
4585 : (may_use_blx
4586 ? arm_stub_long_branch_any_any // V5T and above.
4587 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4588 }
4589 }
4590 else
4591 {
4592 // Arm to arm.
4593 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4594 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4595 {
4596 stub_type = (output_is_position_independent
4597 || should_force_pic_veneer)
4598 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4599 : arm_stub_long_branch_any_any; /// non-PIC.
4600 }
4601 }
4602 }
4603
4604 return stub_type;
4605 }
4606
4607 // Cortex_a8_stub methods.
4608
4609 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4610 // I is the position of the instruction template in the stub template.
4611
4612 uint16_t
4613 Cortex_a8_stub::do_thumb16_special(size_t i)
4614 {
4615 // The only use of this is to copy condition code from a conditional
4616 // branch being worked around to the corresponding conditional branch in
4617 // to the stub.
4618 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4619 && i == 0);
4620 uint16_t data = this->stub_template()->insns()[i].data();
4621 gold_assert((data & 0xff00U) == 0xd000U);
4622 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4623 return data;
4624 }
4625
4626 // Stub_factory methods.
4627
4628 Stub_factory::Stub_factory()
4629 {
4630 // The instruction template sequences are declared as static
4631 // objects and initialized first time the constructor runs.
4632
4633 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4634 // to reach the stub if necessary.
4635 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4636 {
4637 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4638 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4639 // dcd R_ARM_ABS32(X)
4640 };
4641
4642 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4643 // available.
4644 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4645 {
4646 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4647 Insn_template::arm_insn(0xe12fff1c), // bx ip
4648 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4649 // dcd R_ARM_ABS32(X)
4650 };
4651
4652 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4653 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4654 {
4655 Insn_template::thumb16_insn(0xb401), // push {r0}
4656 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4657 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4658 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4659 Insn_template::thumb16_insn(0x4760), // bx ip
4660 Insn_template::thumb16_insn(0xbf00), // nop
4661 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4662 // dcd R_ARM_ABS32(X)
4663 };
4664
4665 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4666 // allowed.
4667 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4668 {
4669 Insn_template::thumb16_insn(0x4778), // bx pc
4670 Insn_template::thumb16_insn(0x46c0), // nop
4671 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4672 Insn_template::arm_insn(0xe12fff1c), // bx ip
4673 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4674 // dcd R_ARM_ABS32(X)
4675 };
4676
4677 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4678 // available.
4679 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4680 {
4681 Insn_template::thumb16_insn(0x4778), // bx pc
4682 Insn_template::thumb16_insn(0x46c0), // nop
4683 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4684 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4685 // dcd R_ARM_ABS32(X)
4686 };
4687
4688 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4689 // one, when the destination is close enough.
4690 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4691 {
4692 Insn_template::thumb16_insn(0x4778), // bx pc
4693 Insn_template::thumb16_insn(0x46c0), // nop
4694 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4695 };
4696
4697 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4698 // blx to reach the stub if necessary.
4699 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4700 {
4701 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4702 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4703 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4704 // dcd R_ARM_REL32(X-4)
4705 };
4706
4707 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4708 // blx to reach the stub if necessary. We can not add into pc;
4709 // it is not guaranteed to mode switch (different in ARMv6 and
4710 // ARMv7).
4711 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4712 {
4713 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4714 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4715 Insn_template::arm_insn(0xe12fff1c), // bx ip
4716 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4717 // dcd R_ARM_REL32(X)
4718 };
4719
4720 // V4T ARM -> ARM long branch stub, PIC.
4721 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4722 {
4723 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4724 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4725 Insn_template::arm_insn(0xe12fff1c), // bx ip
4726 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4727 // dcd R_ARM_REL32(X)
4728 };
4729
4730 // V4T Thumb -> ARM long branch stub, PIC.
4731 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4732 {
4733 Insn_template::thumb16_insn(0x4778), // bx pc
4734 Insn_template::thumb16_insn(0x46c0), // nop
4735 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4736 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4737 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4738 // dcd R_ARM_REL32(X)
4739 };
4740
4741 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4742 // architectures.
4743 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4744 {
4745 Insn_template::thumb16_insn(0xb401), // push {r0}
4746 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4747 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4748 Insn_template::thumb16_insn(0x4484), // add ip, r0
4749 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4750 Insn_template::thumb16_insn(0x4760), // bx ip
4751 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4752 // dcd R_ARM_REL32(X)
4753 };
4754
4755 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4756 // allowed.
4757 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4758 {
4759 Insn_template::thumb16_insn(0x4778), // bx pc
4760 Insn_template::thumb16_insn(0x46c0), // nop
4761 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4762 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4763 Insn_template::arm_insn(0xe12fff1c), // bx ip
4764 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4765 // dcd R_ARM_REL32(X)
4766 };
4767
4768 // Cortex-A8 erratum-workaround stubs.
4769
4770 // Stub used for conditional branches (which may be beyond +/-1MB away,
4771 // so we can't use a conditional branch to reach this stub).
4772
4773 // original code:
4774 //
4775 // b<cond> X
4776 // after:
4777 //
4778 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4779 {
4780 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4781 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4782 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4783 // b.w X
4784 };
4785
4786 // Stub used for b.w and bl.w instructions.
4787
4788 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4789 {
4790 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4791 };
4792
4793 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4794 {
4795 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4796 };
4797
4798 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4799 // instruction (which switches to ARM mode) to point to this stub. Jump to
4800 // the real destination using an ARM-mode branch.
4801 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4802 {
4803 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4804 };
4805
4806 // Stub used to provide an interworking for R_ARM_V4BX relocation
4807 // (bx r[n] instruction).
4808 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4809 {
4810 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4811 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4812 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4813 };
4814
4815 // Fill in the stub template look-up table. Stub templates are constructed
4816 // per instance of Stub_factory for fast look-up without locking
4817 // in a thread-enabled environment.
4818
4819 this->stub_templates_[arm_stub_none] =
4820 new Stub_template(arm_stub_none, NULL, 0);
4821
4822 #define DEF_STUB(x) \
4823 do \
4824 { \
4825 size_t array_size \
4826 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4827 Stub_type type = arm_stub_##x; \
4828 this->stub_templates_[type] = \
4829 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4830 } \
4831 while (0);
4832
4833 DEF_STUBS
4834 #undef DEF_STUB
4835 }
4836
4837 // Stub_table methods.
4838
4839 // Remove all Cortex-A8 stub.
4840
4841 template<bool big_endian>
4842 void
4843 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4844 {
4845 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4846 p != this->cortex_a8_stubs_.end();
4847 ++p)
4848 delete p->second;
4849 this->cortex_a8_stubs_.clear();
4850 }
4851
4852 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4853
4854 template<bool big_endian>
4855 void
4856 Stub_table<big_endian>::relocate_stub(
4857 Stub* stub,
4858 const Relocate_info<32, big_endian>* relinfo,
4859 Target_arm<big_endian>* arm_target,
4860 Output_section* output_section,
4861 unsigned char* view,
4862 Arm_address address,
4863 section_size_type view_size)
4864 {
4865 const Stub_template* stub_template = stub->stub_template();
4866 if (stub_template->reloc_count() != 0)
4867 {
4868 // Adjust view to cover the stub only.
4869 section_size_type offset = stub->offset();
4870 section_size_type stub_size = stub_template->size();
4871 gold_assert(offset + stub_size <= view_size);
4872
4873 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4874 address + offset, stub_size);
4875 }
4876 }
4877
4878 // Relocate all stubs in this stub table.
4879
4880 template<bool big_endian>
4881 void
4882 Stub_table<big_endian>::relocate_stubs(
4883 const Relocate_info<32, big_endian>* relinfo,
4884 Target_arm<big_endian>* arm_target,
4885 Output_section* output_section,
4886 unsigned char* view,
4887 Arm_address address,
4888 section_size_type view_size)
4889 {
4890 // If we are passed a view bigger than the stub table's. we need to
4891 // adjust the view.
4892 gold_assert(address == this->address()
4893 && (view_size
4894 == static_cast<section_size_type>(this->data_size())));
4895
4896 // Relocate all relocation stubs.
4897 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4898 p != this->reloc_stubs_.end();
4899 ++p)
4900 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4901 address, view_size);
4902
4903 // Relocate all Cortex-A8 stubs.
4904 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4905 p != this->cortex_a8_stubs_.end();
4906 ++p)
4907 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4908 address, view_size);
4909
4910 // Relocate all ARM V4BX stubs.
4911 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4912 p != this->arm_v4bx_stubs_.end();
4913 ++p)
4914 {
4915 if (*p != NULL)
4916 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4917 address, view_size);
4918 }
4919 }
4920
4921 // Write out the stubs to file.
4922
4923 template<bool big_endian>
4924 void
4925 Stub_table<big_endian>::do_write(Output_file* of)
4926 {
4927 off_t offset = this->offset();
4928 const section_size_type oview_size =
4929 convert_to_section_size_type(this->data_size());
4930 unsigned char* const oview = of->get_output_view(offset, oview_size);
4931
4932 // Write relocation stubs.
4933 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4934 p != this->reloc_stubs_.end();
4935 ++p)
4936 {
4937 Reloc_stub* stub = p->second;
4938 Arm_address address = this->address() + stub->offset();
4939 gold_assert(address
4940 == align_address(address,
4941 stub->stub_template()->alignment()));
4942 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4943 big_endian);
4944 }
4945
4946 // Write Cortex-A8 stubs.
4947 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4948 p != this->cortex_a8_stubs_.end();
4949 ++p)
4950 {
4951 Cortex_a8_stub* stub = p->second;
4952 Arm_address address = this->address() + stub->offset();
4953 gold_assert(address
4954 == align_address(address,
4955 stub->stub_template()->alignment()));
4956 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4957 big_endian);
4958 }
4959
4960 // Write ARM V4BX relocation stubs.
4961 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4962 p != this->arm_v4bx_stubs_.end();
4963 ++p)
4964 {
4965 if (*p == NULL)
4966 continue;
4967
4968 Arm_address address = this->address() + (*p)->offset();
4969 gold_assert(address
4970 == align_address(address,
4971 (*p)->stub_template()->alignment()));
4972 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4973 big_endian);
4974 }
4975
4976 of->write_output_view(this->offset(), oview_size, oview);
4977 }
4978
4979 // Update the data size and address alignment of the stub table at the end
4980 // of a relaxation pass. Return true if either the data size or the
4981 // alignment changed in this relaxation pass.
4982
4983 template<bool big_endian>
4984 bool
4985 Stub_table<big_endian>::update_data_size_and_addralign()
4986 {
4987 // Go over all stubs in table to compute data size and address alignment.
4988 off_t size = this->reloc_stubs_size_;
4989 unsigned addralign = this->reloc_stubs_addralign_;
4990
4991 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4992 p != this->cortex_a8_stubs_.end();
4993 ++p)
4994 {
4995 const Stub_template* stub_template = p->second->stub_template();
4996 addralign = std::max(addralign, stub_template->alignment());
4997 size = (align_address(size, stub_template->alignment())
4998 + stub_template->size());
4999 }
5000
5001 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
5002 p != this->arm_v4bx_stubs_.end();
5003 ++p)
5004 {
5005 if (*p == NULL)
5006 continue;
5007
5008 const Stub_template* stub_template = (*p)->stub_template();
5009 addralign = std::max(addralign, stub_template->alignment());
5010 size = (align_address(size, stub_template->alignment())
5011 + stub_template->size());
5012 }
5013
5014 // Check if either data size or alignment changed in this pass.
5015 // Update prev_data_size_ and prev_addralign_. These will be used
5016 // as the current data size and address alignment for the next pass.
5017 bool changed = size != this->prev_data_size_;
5018 this->prev_data_size_ = size;
5019
5020 if (addralign != this->prev_addralign_)
5021 changed = true;
5022 this->prev_addralign_ = addralign;
5023
5024 return changed;
5025 }
5026
5027 // Finalize the stubs. This sets the offsets of the stubs within the stub
5028 // table. It also marks all input sections needing Cortex-A8 workaround.
5029
5030 template<bool big_endian>
5031 void
5032 Stub_table<big_endian>::finalize_stubs()
5033 {
5034 off_t off = this->reloc_stubs_size_;
5035 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
5036 p != this->cortex_a8_stubs_.end();
5037 ++p)
5038 {
5039 Cortex_a8_stub* stub = p->second;
5040 const Stub_template* stub_template = stub->stub_template();
5041 uint64_t stub_addralign = stub_template->alignment();
5042 off = align_address(off, stub_addralign);
5043 stub->set_offset(off);
5044 off += stub_template->size();
5045
5046 // Mark input section so that we can determine later if a code section
5047 // needs the Cortex-A8 workaround quickly.
5048 Arm_relobj<big_endian>* arm_relobj =
5049 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
5050 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
5051 }
5052
5053 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
5054 p != this->arm_v4bx_stubs_.end();
5055 ++p)
5056 {
5057 if (*p == NULL)
5058 continue;
5059
5060 const Stub_template* stub_template = (*p)->stub_template();
5061 uint64_t stub_addralign = stub_template->alignment();
5062 off = align_address(off, stub_addralign);
5063 (*p)->set_offset(off);
5064 off += stub_template->size();
5065 }
5066
5067 gold_assert(off <= this->prev_data_size_);
5068 }
5069
5070 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
5071 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
5072 // of the address range seen by the linker.
5073
5074 template<bool big_endian>
5075 void
5076 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
5077 Target_arm<big_endian>* arm_target,
5078 unsigned char* view,
5079 Arm_address view_address,
5080 section_size_type view_size)
5081 {
5082 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
5083 for (Cortex_a8_stub_list::const_iterator p =
5084 this->cortex_a8_stubs_.lower_bound(view_address);
5085 ((p != this->cortex_a8_stubs_.end())
5086 && (p->first < (view_address + view_size)));
5087 ++p)
5088 {
5089 // We do not store the THUMB bit in the LSB of either the branch address
5090 // or the stub offset. There is no need to strip the LSB.
5091 Arm_address branch_address = p->first;
5092 const Cortex_a8_stub* stub = p->second;
5093 Arm_address stub_address = this->address() + stub->offset();
5094
5095 // Offset of the branch instruction relative to this view.
5096 section_size_type offset =
5097 convert_to_section_size_type(branch_address - view_address);
5098 gold_assert((offset + 4) <= view_size);
5099
5100 arm_target->apply_cortex_a8_workaround(stub, stub_address,
5101 view + offset, branch_address);
5102 }
5103 }
5104
5105 // Arm_input_section methods.
5106
5107 // Initialize an Arm_input_section.
5108
5109 template<bool big_endian>
5110 void
5111 Arm_input_section<big_endian>::init()
5112 {
5113 Relobj* relobj = this->relobj();
5114 unsigned int shndx = this->shndx();
5115
5116 // We have to cache original size, alignment and contents to avoid locking
5117 // the original file.
5118 this->original_addralign_ =
5119 convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
5120
5121 // This is not efficient but we expect only a small number of relaxed
5122 // input sections for stubs.
5123 section_size_type section_size;
5124 const unsigned char* section_contents =
5125 relobj->section_contents(shndx, &section_size, false);
5126 this->original_size_ =
5127 convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
5128
5129 gold_assert(this->original_contents_ == NULL);
5130 this->original_contents_ = new unsigned char[section_size];
5131 memcpy(this->original_contents_, section_contents, section_size);
5132
5133 // We want to make this look like the original input section after
5134 // output sections are finalized.
5135 Output_section* os = relobj->output_section(shndx);
5136 off_t offset = relobj->output_section_offset(shndx);
5137 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
5138 this->set_address(os->address() + offset);
5139 this->set_file_offset(os->offset() + offset);
5140
5141 this->set_current_data_size(this->original_size_);
5142 this->finalize_data_size();
5143 }
5144
5145 template<bool big_endian>
5146 void
5147 Arm_input_section<big_endian>::do_write(Output_file* of)
5148 {
5149 // We have to write out the original section content.
5150 gold_assert(this->original_contents_ != NULL);
5151 of->write(this->offset(), this->original_contents_,
5152 this->original_size_);
5153
5154 // If this owns a stub table and it is not empty, write it.
5155 if (this->is_stub_table_owner() && !this->stub_table_->empty())
5156 this->stub_table_->write(of);
5157 }
5158
5159 // Finalize data size.
5160
5161 template<bool big_endian>
5162 void
5163 Arm_input_section<big_endian>::set_final_data_size()
5164 {
5165 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5166
5167 if (this->is_stub_table_owner())
5168 {
5169 this->stub_table_->finalize_data_size();
5170 off = align_address(off, this->stub_table_->addralign());
5171 off += this->stub_table_->data_size();
5172 }
5173 this->set_data_size(off);
5174 }
5175
5176 // Reset address and file offset.
5177
5178 template<bool big_endian>
5179 void
5180 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
5181 {
5182 // Size of the original input section contents.
5183 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5184
5185 // If this is a stub table owner, account for the stub table size.
5186 if (this->is_stub_table_owner())
5187 {
5188 Stub_table<big_endian>* stub_table = this->stub_table_;
5189
5190 // Reset the stub table's address and file offset. The
5191 // current data size for child will be updated after that.
5192 stub_table_->reset_address_and_file_offset();
5193 off = align_address(off, stub_table_->addralign());
5194 off += stub_table->current_data_size();
5195 }
5196
5197 this->set_current_data_size(off);
5198 }
5199
5200 // Arm_exidx_cantunwind methods.
5201
5202 // Write this to Output file OF for a fixed endianness.
5203
5204 template<bool big_endian>
5205 void
5206 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
5207 {
5208 off_t offset = this->offset();
5209 const section_size_type oview_size = 8;
5210 unsigned char* const oview = of->get_output_view(offset, oview_size);
5211
5212 Output_section* os = this->relobj_->output_section(this->shndx_);
5213 gold_assert(os != NULL);
5214
5215 Arm_relobj<big_endian>* arm_relobj =
5216 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
5217 Arm_address output_offset =
5218 arm_relobj->get_output_section_offset(this->shndx_);
5219 Arm_address section_start;
5220 section_size_type section_size;
5221
5222 // Find out the end of the text section referred by this.
5223 if (output_offset != Arm_relobj<big_endian>::invalid_address)
5224 {
5225 section_start = os->address() + output_offset;
5226 const Arm_exidx_input_section* exidx_input_section =
5227 arm_relobj->exidx_input_section_by_link(this->shndx_);
5228 gold_assert(exidx_input_section != NULL);
5229 section_size =
5230 convert_to_section_size_type(exidx_input_section->text_size());
5231 }
5232 else
5233 {
5234 // Currently this only happens for a relaxed section.
5235 const Output_relaxed_input_section* poris =
5236 os->find_relaxed_input_section(this->relobj_, this->shndx_);
5237 gold_assert(poris != NULL);
5238 section_start = poris->address();
5239 section_size = convert_to_section_size_type(poris->data_size());
5240 }
5241
5242 // We always append this to the end of an EXIDX section.
5243 Arm_address output_address = section_start + section_size;
5244
5245 // Write out the entry. The first word either points to the beginning
5246 // or after the end of a text section. The second word is the special
5247 // EXIDX_CANTUNWIND value.
5248 uint32_t prel31_offset = output_address - this->address();
5249 if (Bits<31>::has_overflow32(offset))
5250 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
5251 elfcpp::Swap_unaligned<32, big_endian>::writeval(oview,
5252 prel31_offset & 0x7fffffffU);
5253 elfcpp::Swap_unaligned<32, big_endian>::writeval(oview + 4,
5254 elfcpp::EXIDX_CANTUNWIND);
5255
5256 of->write_output_view(this->offset(), oview_size, oview);
5257 }
5258
5259 // Arm_exidx_merged_section methods.
5260
5261 // Constructor for Arm_exidx_merged_section.
5262 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5263 // SECTION_OFFSET_MAP points to a section offset map describing how
5264 // parts of the input section are mapped to output. DELETED_BYTES is
5265 // the number of bytes deleted from the EXIDX input section.
5266
5267 Arm_exidx_merged_section::Arm_exidx_merged_section(
5268 const Arm_exidx_input_section& exidx_input_section,
5269 const Arm_exidx_section_offset_map& section_offset_map,
5270 uint32_t deleted_bytes)
5271 : Output_relaxed_input_section(exidx_input_section.relobj(),
5272 exidx_input_section.shndx(),
5273 exidx_input_section.addralign()),
5274 exidx_input_section_(exidx_input_section),
5275 section_offset_map_(section_offset_map)
5276 {
5277 // If we retain or discard the whole EXIDX input section, we would
5278 // not be here.
5279 gold_assert(deleted_bytes != 0
5280 && deleted_bytes != this->exidx_input_section_.size());
5281
5282 // Fix size here so that we do not need to implement set_final_data_size.
5283 uint32_t size = exidx_input_section.size() - deleted_bytes;
5284 this->set_data_size(size);
5285 this->fix_data_size();
5286
5287 // Allocate buffer for section contents and build contents.
5288 this->section_contents_ = new unsigned char[size];
5289 }
5290
5291 // Build the contents of a merged EXIDX output section.
5292
5293 void
5294 Arm_exidx_merged_section::build_contents(
5295 const unsigned char* original_contents,
5296 section_size_type original_size)
5297 {
5298 // Go over spans of input offsets and write only those that are not
5299 // discarded.
5300 section_offset_type in_start = 0;
5301 section_offset_type out_start = 0;
5302 section_offset_type in_max =
5303 convert_types<section_offset_type>(original_size);
5304 section_offset_type out_max =
5305 convert_types<section_offset_type>(this->data_size());
5306 for (Arm_exidx_section_offset_map::const_iterator p =
5307 this->section_offset_map_.begin();
5308 p != this->section_offset_map_.end();
5309 ++p)
5310 {
5311 section_offset_type in_end = p->first;
5312 gold_assert(in_end >= in_start);
5313 section_offset_type out_end = p->second;
5314 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5315 if (out_end != -1)
5316 {
5317 size_t out_chunk_size =
5318 convert_types<size_t>(out_end - out_start + 1);
5319
5320 gold_assert(out_chunk_size == in_chunk_size
5321 && in_end < in_max && out_end < out_max);
5322
5323 memcpy(this->section_contents_ + out_start,
5324 original_contents + in_start,
5325 out_chunk_size);
5326 out_start += out_chunk_size;
5327 }
5328 in_start += in_chunk_size;
5329 }
5330 }
5331
5332 // Given an input OBJECT, an input section index SHNDX within that
5333 // object, and an OFFSET relative to the start of that input
5334 // section, return whether or not the corresponding offset within
5335 // the output section is known. If this function returns true, it
5336 // sets *POUTPUT to the output offset. The value -1 indicates that
5337 // this input offset is being discarded.
5338
5339 bool
5340 Arm_exidx_merged_section::do_output_offset(
5341 const Relobj* relobj,
5342 unsigned int shndx,
5343 section_offset_type offset,
5344 section_offset_type* poutput) const
5345 {
5346 // We only handle offsets for the original EXIDX input section.
5347 if (relobj != this->exidx_input_section_.relobj()
5348 || shndx != this->exidx_input_section_.shndx())
5349 return false;
5350
5351 section_offset_type section_size =
5352 convert_types<section_offset_type>(this->exidx_input_section_.size());
5353 if (offset < 0 || offset >= section_size)
5354 // Input offset is out of valid range.
5355 *poutput = -1;
5356 else
5357 {
5358 // We need to look up the section offset map to determine the output
5359 // offset. Find the reference point in map that is first offset
5360 // bigger than or equal to this offset.
5361 Arm_exidx_section_offset_map::const_iterator p =
5362 this->section_offset_map_.lower_bound(offset);
5363
5364 // The section offset maps are build such that this should not happen if
5365 // input offset is in the valid range.
5366 gold_assert(p != this->section_offset_map_.end());
5367
5368 // We need to check if this is dropped.
5369 section_offset_type ref = p->first;
5370 section_offset_type mapped_ref = p->second;
5371
5372 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5373 // Offset is present in output.
5374 *poutput = mapped_ref + (offset - ref);
5375 else
5376 // Offset is discarded owing to EXIDX entry merging.
5377 *poutput = -1;
5378 }
5379
5380 return true;
5381 }
5382
5383 // Write this to output file OF.
5384
5385 void
5386 Arm_exidx_merged_section::do_write(Output_file* of)
5387 {
5388 off_t offset = this->offset();
5389 const section_size_type oview_size = this->data_size();
5390 unsigned char* const oview = of->get_output_view(offset, oview_size);
5391
5392 Output_section* os = this->relobj()->output_section(this->shndx());
5393 gold_assert(os != NULL);
5394
5395 memcpy(oview, this->section_contents_, oview_size);
5396 of->write_output_view(this->offset(), oview_size, oview);
5397 }
5398
5399 // Arm_exidx_fixup methods.
5400
5401 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5402 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5403 // points to the end of the last seen EXIDX section.
5404
5405 void
5406 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5407 {
5408 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5409 && this->last_input_section_ != NULL)
5410 {
5411 Relobj* relobj = this->last_input_section_->relobj();
5412 unsigned int text_shndx = this->last_input_section_->link();
5413 Arm_exidx_cantunwind* cantunwind =
5414 new Arm_exidx_cantunwind(relobj, text_shndx);
5415 this->exidx_output_section_->add_output_section_data(cantunwind);
5416 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5417 }
5418 }
5419
5420 // Process an EXIDX section entry in input. Return whether this entry
5421 // can be deleted in the output. SECOND_WORD in the second word of the
5422 // EXIDX entry.
5423
5424 bool
5425 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5426 {
5427 bool delete_entry;
5428 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5429 {
5430 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5431 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5432 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5433 }
5434 else if ((second_word & 0x80000000) != 0)
5435 {
5436 // Inlined unwinding data. Merge if equal to previous.
5437 delete_entry = (merge_exidx_entries_
5438 && this->last_unwind_type_ == UT_INLINED_ENTRY
5439 && this->last_inlined_entry_ == second_word);
5440 this->last_unwind_type_ = UT_INLINED_ENTRY;
5441 this->last_inlined_entry_ = second_word;
5442 }
5443 else
5444 {
5445 // Normal table entry. In theory we could merge these too,
5446 // but duplicate entries are likely to be much less common.
5447 delete_entry = false;
5448 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5449 }
5450 return delete_entry;
5451 }
5452
5453 // Update the current section offset map during EXIDX section fix-up.
5454 // If there is no map, create one. INPUT_OFFSET is the offset of a
5455 // reference point, DELETED_BYTES is the number of deleted by in the
5456 // section so far. If DELETE_ENTRY is true, the reference point and
5457 // all offsets after the previous reference point are discarded.
5458
5459 void
5460 Arm_exidx_fixup::update_offset_map(
5461 section_offset_type input_offset,
5462 section_size_type deleted_bytes,
5463 bool delete_entry)
5464 {
5465 if (this->section_offset_map_ == NULL)
5466 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5467 section_offset_type output_offset;
5468 if (delete_entry)
5469 output_offset = Arm_exidx_input_section::invalid_offset;
5470 else
5471 output_offset = input_offset - deleted_bytes;
5472 (*this->section_offset_map_)[input_offset] = output_offset;
5473 }
5474
5475 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5476 // bytes deleted. SECTION_CONTENTS points to the contents of the EXIDX
5477 // section and SECTION_SIZE is the number of bytes pointed by SECTION_CONTENTS.
5478 // If some entries are merged, also store a pointer to a newly created
5479 // Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The caller
5480 // owns the map and is responsible for releasing it after use.
5481
5482 template<bool big_endian>
5483 uint32_t
5484 Arm_exidx_fixup::process_exidx_section(
5485 const Arm_exidx_input_section* exidx_input_section,
5486 const unsigned char* section_contents,
5487 section_size_type section_size,
5488 Arm_exidx_section_offset_map** psection_offset_map)
5489 {
5490 Relobj* relobj = exidx_input_section->relobj();
5491 unsigned shndx = exidx_input_section->shndx();
5492
5493 if ((section_size % 8) != 0)
5494 {
5495 // Something is wrong with this section. Better not touch it.
5496 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5497 relobj->name().c_str(), shndx);
5498 this->last_input_section_ = exidx_input_section;
5499 this->last_unwind_type_ = UT_NONE;
5500 return 0;
5501 }
5502
5503 uint32_t deleted_bytes = 0;
5504 bool prev_delete_entry = false;
5505 gold_assert(this->section_offset_map_ == NULL);
5506
5507 for (section_size_type i = 0; i < section_size; i += 8)
5508 {
5509 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5510 const Valtype* wv =
5511 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5512 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5513
5514 bool delete_entry = this->process_exidx_entry(second_word);
5515
5516 // Entry deletion causes changes in output offsets. We use a std::map
5517 // to record these. And entry (x, y) means input offset x
5518 // is mapped to output offset y. If y is invalid_offset, then x is
5519 // dropped in the output. Because of the way std::map::lower_bound
5520 // works, we record the last offset in a region w.r.t to keeping or
5521 // dropping. If there is no entry (x0, y0) for an input offset x0,
5522 // the output offset y0 of it is determined by the output offset y1 of
5523 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5524 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Otherwise, y1
5525 // y0 is also -1.
5526 if (delete_entry != prev_delete_entry && i != 0)
5527 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5528
5529 // Update total deleted bytes for this entry.
5530 if (delete_entry)
5531 deleted_bytes += 8;
5532
5533 prev_delete_entry = delete_entry;
5534 }
5535
5536 // If section offset map is not NULL, make an entry for the end of
5537 // section.
5538 if (this->section_offset_map_ != NULL)
5539 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5540
5541 *psection_offset_map = this->section_offset_map_;
5542 this->section_offset_map_ = NULL;
5543 this->last_input_section_ = exidx_input_section;
5544
5545 // Set the first output text section so that we can link the EXIDX output
5546 // section to it. Ignore any EXIDX input section that is completely merged.
5547 if (this->first_output_text_section_ == NULL
5548 && deleted_bytes != section_size)
5549 {
5550 unsigned int link = exidx_input_section->link();
5551 Output_section* os = relobj->output_section(link);
5552 gold_assert(os != NULL);
5553 this->first_output_text_section_ = os;
5554 }
5555
5556 return deleted_bytes;
5557 }
5558
5559 // Arm_output_section methods.
5560
5561 // Create a stub group for input sections from BEGIN to END. OWNER
5562 // points to the input section to be the owner a new stub table.
5563
5564 template<bool big_endian>
5565 void
5566 Arm_output_section<big_endian>::create_stub_group(
5567 Input_section_list::const_iterator begin,
5568 Input_section_list::const_iterator end,
5569 Input_section_list::const_iterator owner,
5570 Target_arm<big_endian>* target,
5571 std::vector<Output_relaxed_input_section*>* new_relaxed_sections,
5572 const Task* task)
5573 {
5574 // We use a different kind of relaxed section in an EXIDX section.
5575 // The static casting from Output_relaxed_input_section to
5576 // Arm_input_section is invalid in an EXIDX section. We are okay
5577 // because we should not be calling this for an EXIDX section.
5578 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5579
5580 // Currently we convert ordinary input sections into relaxed sections only
5581 // at this point but we may want to support creating relaxed input section
5582 // very early. So we check here to see if owner is already a relaxed
5583 // section.
5584
5585 Arm_input_section<big_endian>* arm_input_section;
5586 if (owner->is_relaxed_input_section())
5587 {
5588 arm_input_section =
5589 Arm_input_section<big_endian>::as_arm_input_section(
5590 owner->relaxed_input_section());
5591 }
5592 else
5593 {
5594 gold_assert(owner->is_input_section());
5595 // Create a new relaxed input section. We need to lock the original
5596 // file.
5597 Task_lock_obj<Object> tl(task, owner->relobj());
5598 arm_input_section =
5599 target->new_arm_input_section(owner->relobj(), owner->shndx());
5600 new_relaxed_sections->push_back(arm_input_section);
5601 }
5602
5603 // Create a stub table.
5604 Stub_table<big_endian>* stub_table =
5605 target->new_stub_table(arm_input_section);
5606
5607 arm_input_section->set_stub_table(stub_table);
5608
5609 Input_section_list::const_iterator p = begin;
5610 Input_section_list::const_iterator prev_p;
5611
5612 // Look for input sections or relaxed input sections in [begin ... end].
5613 do
5614 {
5615 if (p->is_input_section() || p->is_relaxed_input_section())
5616 {
5617 // The stub table information for input sections live
5618 // in their objects.
5619 Arm_relobj<big_endian>* arm_relobj =
5620 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5621 arm_relobj->set_stub_table(p->shndx(), stub_table);
5622 }
5623 prev_p = p++;
5624 }
5625 while (prev_p != end);
5626 }
5627
5628 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5629 // of stub groups. We grow a stub group by adding input section until the
5630 // size is just below GROUP_SIZE. The last input section will be converted
5631 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5632 // input section after the stub table, effectively double the group size.
5633 //
5634 // This is similar to the group_sections() function in elf32-arm.c but is
5635 // implemented differently.
5636
5637 template<bool big_endian>
5638 void
5639 Arm_output_section<big_endian>::group_sections(
5640 section_size_type group_size,
5641 bool stubs_always_after_branch,
5642 Target_arm<big_endian>* target,
5643 const Task* task)
5644 {
5645 // We only care about sections containing code.
5646 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5647 return;
5648
5649 // States for grouping.
5650 typedef enum
5651 {
5652 // No group is being built.
5653 NO_GROUP,
5654 // A group is being built but the stub table is not found yet.
5655 // We keep group a stub group until the size is just under GROUP_SIZE.
5656 // The last input section in the group will be used as the stub table.
5657 FINDING_STUB_SECTION,
5658 // A group is being built and we have already found a stub table.
5659 // We enter this state to grow a stub group by adding input section
5660 // after the stub table. This effectively doubles the group size.
5661 HAS_STUB_SECTION
5662 } State;
5663
5664 // Any newly created relaxed sections are stored here.
5665 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5666
5667 State state = NO_GROUP;
5668 section_size_type off = 0;
5669 section_size_type group_begin_offset = 0;
5670 section_size_type group_end_offset = 0;
5671 section_size_type stub_table_end_offset = 0;
5672 Input_section_list::const_iterator group_begin =
5673 this->input_sections().end();
5674 Input_section_list::const_iterator stub_table =
5675 this->input_sections().end();
5676 Input_section_list::const_iterator group_end = this->input_sections().end();
5677 for (Input_section_list::const_iterator p = this->input_sections().begin();
5678 p != this->input_sections().end();
5679 ++p)
5680 {
5681 section_size_type section_begin_offset =
5682 align_address(off, p->addralign());
5683 section_size_type section_end_offset =
5684 section_begin_offset + p->data_size();
5685
5686 // Check to see if we should group the previously seen sections.
5687 switch (state)
5688 {
5689 case NO_GROUP:
5690 break;
5691
5692 case FINDING_STUB_SECTION:
5693 // Adding this section makes the group larger than GROUP_SIZE.
5694 if (section_end_offset - group_begin_offset >= group_size)
5695 {
5696 if (stubs_always_after_branch)
5697 {
5698 gold_assert(group_end != this->input_sections().end());
5699 this->create_stub_group(group_begin, group_end, group_end,
5700 target, &new_relaxed_sections,
5701 task);
5702 state = NO_GROUP;
5703 }
5704 else
5705 {
5706 // But wait, there's more! Input sections up to
5707 // stub_group_size bytes after the stub table can be
5708 // handled by it too.
5709 state = HAS_STUB_SECTION;
5710 stub_table = group_end;
5711 stub_table_end_offset = group_end_offset;
5712 }
5713 }
5714 break;
5715
5716 case HAS_STUB_SECTION:
5717 // Adding this section makes the post stub-section group larger
5718 // than GROUP_SIZE.
5719 if (section_end_offset - stub_table_end_offset >= group_size)
5720 {
5721 gold_assert(group_end != this->input_sections().end());
5722 this->create_stub_group(group_begin, group_end, stub_table,
5723 target, &new_relaxed_sections, task);
5724 state = NO_GROUP;
5725 }
5726 break;
5727
5728 default:
5729 gold_unreachable();
5730 }
5731
5732 // If we see an input section and currently there is no group, start
5733 // a new one. Skip any empty sections. We look at the data size
5734 // instead of calling p->relobj()->section_size() to avoid locking.
5735 if ((p->is_input_section() || p->is_relaxed_input_section())
5736 && (p->data_size() != 0))
5737 {
5738 if (state == NO_GROUP)
5739 {
5740 state = FINDING_STUB_SECTION;
5741 group_begin = p;
5742 group_begin_offset = section_begin_offset;
5743 }
5744
5745 // Keep track of the last input section seen.
5746 group_end = p;
5747 group_end_offset = section_end_offset;
5748 }
5749
5750 off = section_end_offset;
5751 }
5752
5753 // Create a stub group for any ungrouped sections.
5754 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5755 {
5756 gold_assert(group_end != this->input_sections().end());
5757 this->create_stub_group(group_begin, group_end,
5758 (state == FINDING_STUB_SECTION
5759 ? group_end
5760 : stub_table),
5761 target, &new_relaxed_sections, task);
5762 }
5763
5764 // Convert input section into relaxed input section in a batch.
5765 if (!new_relaxed_sections.empty())
5766 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5767
5768 // Update the section offsets
5769 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5770 {
5771 Arm_relobj<big_endian>* arm_relobj =
5772 Arm_relobj<big_endian>::as_arm_relobj(
5773 new_relaxed_sections[i]->relobj());
5774 unsigned int shndx = new_relaxed_sections[i]->shndx();
5775 // Tell Arm_relobj that this input section is converted.
5776 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5777 }
5778 }
5779
5780 // Append non empty text sections in this to LIST in ascending
5781 // order of their position in this.
5782
5783 template<bool big_endian>
5784 void
5785 Arm_output_section<big_endian>::append_text_sections_to_list(
5786 Text_section_list* list)
5787 {
5788 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5789
5790 for (Input_section_list::const_iterator p = this->input_sections().begin();
5791 p != this->input_sections().end();
5792 ++p)
5793 {
5794 // We only care about plain or relaxed input sections. We also
5795 // ignore any merged sections.
5796 if (p->is_input_section() || p->is_relaxed_input_section())
5797 list->push_back(Text_section_list::value_type(p->relobj(),
5798 p->shndx()));
5799 }
5800 }
5801
5802 template<bool big_endian>
5803 void
5804 Arm_output_section<big_endian>::fix_exidx_coverage(
5805 Layout* layout,
5806 const Text_section_list& sorted_text_sections,
5807 Symbol_table* symtab,
5808 bool merge_exidx_entries,
5809 const Task* task)
5810 {
5811 // We should only do this for the EXIDX output section.
5812 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5813
5814 // We don't want the relaxation loop to undo these changes, so we discard
5815 // the current saved states and take another one after the fix-up.
5816 this->discard_states();
5817
5818 // Remove all input sections.
5819 uint64_t address = this->address();
5820 typedef std::list<Output_section::Input_section> Input_section_list;
5821 Input_section_list input_sections;
5822 this->reset_address_and_file_offset();
5823 this->get_input_sections(address, std::string(""), &input_sections);
5824
5825 if (!this->input_sections().empty())
5826 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5827
5828 // Go through all the known input sections and record them.
5829 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5830 typedef Unordered_map<Section_id, const Output_section::Input_section*,
5831 Section_id_hash> Text_to_exidx_map;
5832 Text_to_exidx_map text_to_exidx_map;
5833 for (Input_section_list::const_iterator p = input_sections.begin();
5834 p != input_sections.end();
5835 ++p)
5836 {
5837 // This should never happen. At this point, we should only see
5838 // plain EXIDX input sections.
5839 gold_assert(!p->is_relaxed_input_section());
5840 text_to_exidx_map[Section_id(p->relobj(), p->shndx())] = &(*p);
5841 }
5842
5843 Arm_exidx_fixup exidx_fixup(this, merge_exidx_entries);
5844
5845 // Go over the sorted text sections.
5846 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5847 Section_id_set processed_input_sections;
5848 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5849 p != sorted_text_sections.end();
5850 ++p)
5851 {
5852 Relobj* relobj = p->first;
5853 unsigned int shndx = p->second;
5854
5855 Arm_relobj<big_endian>* arm_relobj =
5856 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5857 const Arm_exidx_input_section* exidx_input_section =
5858 arm_relobj->exidx_input_section_by_link(shndx);
5859
5860 // If this text section has no EXIDX section or if the EXIDX section
5861 // has errors, force an EXIDX_CANTUNWIND entry pointing to the end
5862 // of the last seen EXIDX section.
5863 if (exidx_input_section == NULL || exidx_input_section->has_errors())
5864 {
5865 exidx_fixup.add_exidx_cantunwind_as_needed();
5866 continue;
5867 }
5868
5869 Relobj* exidx_relobj = exidx_input_section->relobj();
5870 unsigned int exidx_shndx = exidx_input_section->shndx();
5871 Section_id sid(exidx_relobj, exidx_shndx);
5872 Text_to_exidx_map::const_iterator iter = text_to_exidx_map.find(sid);
5873 if (iter == text_to_exidx_map.end())
5874 {
5875 // This is odd. We have not seen this EXIDX input section before.
5876 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5877 // issue a warning instead. We assume the user knows what he
5878 // or she is doing. Otherwise, this is an error.
5879 if (layout->script_options()->saw_sections_clause())
5880 gold_warning(_("unwinding may not work because EXIDX input section"
5881 " %u of %s is not in EXIDX output section"),
5882 exidx_shndx, exidx_relobj->name().c_str());
5883 else
5884 gold_error(_("unwinding may not work because EXIDX input section"
5885 " %u of %s is not in EXIDX output section"),
5886 exidx_shndx, exidx_relobj->name().c_str());
5887
5888 exidx_fixup.add_exidx_cantunwind_as_needed();
5889 continue;
5890 }
5891
5892 // We need to access the contents of the EXIDX section, lock the
5893 // object here.
5894 Task_lock_obj<Object> tl(task, exidx_relobj);
5895 section_size_type exidx_size;
5896 const unsigned char* exidx_contents =
5897 exidx_relobj->section_contents(exidx_shndx, &exidx_size, false);
5898
5899 // Fix up coverage and append input section to output data list.
5900 Arm_exidx_section_offset_map* section_offset_map = NULL;
5901 uint32_t deleted_bytes =
5902 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5903 exidx_contents,
5904 exidx_size,
5905 &section_offset_map);
5906
5907 if (deleted_bytes == exidx_input_section->size())
5908 {
5909 // The whole EXIDX section got merged. Remove it from output.
5910 gold_assert(section_offset_map == NULL);
5911 exidx_relobj->set_output_section(exidx_shndx, NULL);
5912
5913 // All local symbols defined in this input section will be dropped.
5914 // We need to adjust output local symbol count.
5915 arm_relobj->set_output_local_symbol_count_needs_update();
5916 }
5917 else if (deleted_bytes > 0)
5918 {
5919 // Some entries are merged. We need to convert this EXIDX input
5920 // section into a relaxed section.
5921 gold_assert(section_offset_map != NULL);
5922
5923 Arm_exidx_merged_section* merged_section =
5924 new Arm_exidx_merged_section(*exidx_input_section,
5925 *section_offset_map, deleted_bytes);
5926 merged_section->build_contents(exidx_contents, exidx_size);
5927
5928 const std::string secname = exidx_relobj->section_name(exidx_shndx);
5929 this->add_relaxed_input_section(layout, merged_section, secname);
5930 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5931
5932 // All local symbols defined in discarded portions of this input
5933 // section will be dropped. We need to adjust output local symbol
5934 // count.
5935 arm_relobj->set_output_local_symbol_count_needs_update();
5936 }
5937 else
5938 {
5939 // Just add back the EXIDX input section.
5940 gold_assert(section_offset_map == NULL);
5941 const Output_section::Input_section* pis = iter->second;
5942 gold_assert(pis->is_input_section());
5943 this->add_script_input_section(*pis);
5944 }
5945
5946 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5947 }
5948
5949 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5950 exidx_fixup.add_exidx_cantunwind_as_needed();
5951
5952 // Remove any known EXIDX input sections that are not processed.
5953 for (Input_section_list::const_iterator p = input_sections.begin();
5954 p != input_sections.end();
5955 ++p)
5956 {
5957 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5958 == processed_input_sections.end())
5959 {
5960 // We discard a known EXIDX section because its linked
5961 // text section has been folded by ICF. We also discard an
5962 // EXIDX section with error, the output does not matter in this
5963 // case. We do this to avoid triggering asserts.
5964 Arm_relobj<big_endian>* arm_relobj =
5965 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5966 const Arm_exidx_input_section* exidx_input_section =
5967 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5968 gold_assert(exidx_input_section != NULL);
5969 if (!exidx_input_section->has_errors())
5970 {
5971 unsigned int text_shndx = exidx_input_section->link();
5972 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5973 }
5974
5975 // Remove this from link. We also need to recount the
5976 // local symbols.
5977 p->relobj()->set_output_section(p->shndx(), NULL);
5978 arm_relobj->set_output_local_symbol_count_needs_update();
5979 }
5980 }
5981
5982 // Link exidx output section to the first seen output section and
5983 // set correct entry size.
5984 this->set_link_section(exidx_fixup.first_output_text_section());
5985 this->set_entsize(8);
5986
5987 // Make changes permanent.
5988 this->save_states();
5989 this->set_section_offsets_need_adjustment();
5990 }
5991
5992 // Link EXIDX output sections to text output sections.
5993
5994 template<bool big_endian>
5995 void
5996 Arm_output_section<big_endian>::set_exidx_section_link()
5997 {
5998 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5999 if (!this->input_sections().empty())
6000 {
6001 Input_section_list::const_iterator p = this->input_sections().begin();
6002 Arm_relobj<big_endian>* arm_relobj =
6003 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
6004 unsigned exidx_shndx = p->shndx();
6005 const Arm_exidx_input_section* exidx_input_section =
6006 arm_relobj->exidx_input_section_by_shndx(exidx_shndx);
6007 gold_assert(exidx_input_section != NULL);
6008 unsigned int text_shndx = exidx_input_section->link();
6009 Output_section* os = arm_relobj->output_section(text_shndx);
6010 this->set_link_section(os);
6011 }
6012 }
6013
6014 // Arm_relobj methods.
6015
6016 // Determine if an input section is scannable for stub processing. SHDR is
6017 // the header of the section and SHNDX is the section index. OS is the output
6018 // section for the input section and SYMTAB is the global symbol table used to
6019 // look up ICF information.
6020
6021 template<bool big_endian>
6022 bool
6023 Arm_relobj<big_endian>::section_is_scannable(
6024 const elfcpp::Shdr<32, big_endian>& shdr,
6025 unsigned int shndx,
6026 const Output_section* os,
6027 const Symbol_table* symtab)
6028 {
6029 // Skip any empty sections, unallocated sections or sections whose
6030 // type are not SHT_PROGBITS.
6031 if (shdr.get_sh_size() == 0
6032 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
6033 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
6034 return false;
6035
6036 // Skip any discarded or ICF'ed sections.
6037 if (os == NULL || symtab->is_section_folded(this, shndx))
6038 return false;
6039
6040 // If this requires special offset handling, check to see if it is
6041 // a relaxed section. If this is not, then it is a merged section that
6042 // we cannot handle.
6043 if (this->is_output_section_offset_invalid(shndx))
6044 {
6045 const Output_relaxed_input_section* poris =
6046 os->find_relaxed_input_section(this, shndx);
6047 if (poris == NULL)
6048 return false;
6049 }
6050
6051 return true;
6052 }
6053
6054 // Determine if we want to scan the SHNDX-th section for relocation stubs.
6055 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
6056
6057 template<bool big_endian>
6058 bool
6059 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
6060 const elfcpp::Shdr<32, big_endian>& shdr,
6061 const Relobj::Output_sections& out_sections,
6062 const Symbol_table* symtab,
6063 const unsigned char* pshdrs)
6064 {
6065 unsigned int sh_type = shdr.get_sh_type();
6066 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
6067 return false;
6068
6069 // Ignore empty section.
6070 off_t sh_size = shdr.get_sh_size();
6071 if (sh_size == 0)
6072 return false;
6073
6074 // Ignore reloc section with unexpected symbol table. The
6075 // error will be reported in the final link.
6076 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
6077 return false;
6078
6079 unsigned int reloc_size;
6080 if (sh_type == elfcpp::SHT_REL)
6081 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6082 else
6083 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6084
6085 // Ignore reloc section with unexpected entsize or uneven size.
6086 // The error will be reported in the final link.
6087 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
6088 return false;
6089
6090 // Ignore reloc section with bad info. This error will be
6091 // reported in the final link.
6092 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
6093 if (index >= this->shnum())
6094 return false;
6095
6096 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6097 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
6098 return this->section_is_scannable(text_shdr, index,
6099 out_sections[index], symtab);
6100 }
6101
6102 // Return the output address of either a plain input section or a relaxed
6103 // input section. SHNDX is the section index. We define and use this
6104 // instead of calling Output_section::output_address because that is slow
6105 // for large output.
6106
6107 template<bool big_endian>
6108 Arm_address
6109 Arm_relobj<big_endian>::simple_input_section_output_address(
6110 unsigned int shndx,
6111 Output_section* os)
6112 {
6113 if (this->is_output_section_offset_invalid(shndx))
6114 {
6115 const Output_relaxed_input_section* poris =
6116 os->find_relaxed_input_section(this, shndx);
6117 // We do not handle merged sections here.
6118 gold_assert(poris != NULL);
6119 return poris->address();
6120 }
6121 else
6122 return os->address() + this->get_output_section_offset(shndx);
6123 }
6124
6125 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
6126 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
6127
6128 template<bool big_endian>
6129 bool
6130 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
6131 const elfcpp::Shdr<32, big_endian>& shdr,
6132 unsigned int shndx,
6133 Output_section* os,
6134 const Symbol_table* symtab)
6135 {
6136 if (!this->section_is_scannable(shdr, shndx, os, symtab))
6137 return false;
6138
6139 // If the section does not cross any 4K-boundaries, it does not need to
6140 // be scanned.
6141 Arm_address address = this->simple_input_section_output_address(shndx, os);
6142 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
6143 return false;
6144
6145 return true;
6146 }
6147
6148 // Scan a section for Cortex-A8 workaround.
6149
6150 template<bool big_endian>
6151 void
6152 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
6153 const elfcpp::Shdr<32, big_endian>& shdr,
6154 unsigned int shndx,
6155 Output_section* os,
6156 Target_arm<big_endian>* arm_target)
6157 {
6158 // Look for the first mapping symbol in this section. It should be
6159 // at (shndx, 0).
6160 Mapping_symbol_position section_start(shndx, 0);
6161 typename Mapping_symbols_info::const_iterator p =
6162 this->mapping_symbols_info_.lower_bound(section_start);
6163
6164 // There are no mapping symbols for this section. Treat it as a data-only
6165 // section. Issue a warning if section is marked as containing
6166 // instructions.
6167 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
6168 {
6169 if ((this->section_flags(shndx) & elfcpp::SHF_EXECINSTR) != 0)
6170 gold_warning(_("cannot scan executable section %u of %s for Cortex-A8 "
6171 "erratum because it has no mapping symbols."),
6172 shndx, this->name().c_str());
6173 return;
6174 }
6175
6176 Arm_address output_address =
6177 this->simple_input_section_output_address(shndx, os);
6178
6179 // Get the section contents.
6180 section_size_type input_view_size = 0;
6181 const unsigned char* input_view =
6182 this->section_contents(shndx, &input_view_size, false);
6183
6184 // We need to go through the mapping symbols to determine what to
6185 // scan. There are two reasons. First, we should look at THUMB code and
6186 // THUMB code only. Second, we only want to look at the 4K-page boundary
6187 // to speed up the scanning.
6188
6189 while (p != this->mapping_symbols_info_.end()
6190 && p->first.first == shndx)
6191 {
6192 typename Mapping_symbols_info::const_iterator next =
6193 this->mapping_symbols_info_.upper_bound(p->first);
6194
6195 // Only scan part of a section with THUMB code.
6196 if (p->second == 't')
6197 {
6198 // Determine the end of this range.
6199 section_size_type span_start =
6200 convert_to_section_size_type(p->first.second);
6201 section_size_type span_end;
6202 if (next != this->mapping_symbols_info_.end()
6203 && next->first.first == shndx)
6204 span_end = convert_to_section_size_type(next->first.second);
6205 else
6206 span_end = convert_to_section_size_type(shdr.get_sh_size());
6207
6208 if (((span_start + output_address) & ~0xfffUL)
6209 != ((span_end + output_address - 1) & ~0xfffUL))
6210 {
6211 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
6212 span_start, span_end,
6213 input_view,
6214 output_address);
6215 }
6216 }
6217
6218 p = next;
6219 }
6220 }
6221
6222 // Scan relocations for stub generation.
6223
6224 template<bool big_endian>
6225 void
6226 Arm_relobj<big_endian>::scan_sections_for_stubs(
6227 Target_arm<big_endian>* arm_target,
6228 const Symbol_table* symtab,
6229 const Layout* layout)
6230 {
6231 unsigned int shnum = this->shnum();
6232 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6233
6234 // Read the section headers.
6235 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6236 shnum * shdr_size,
6237 true, true);
6238
6239 // To speed up processing, we set up hash tables for fast lookup of
6240 // input offsets to output addresses.
6241 this->initialize_input_to_output_maps();
6242
6243 const Relobj::Output_sections& out_sections(this->output_sections());
6244
6245 Relocate_info<32, big_endian> relinfo;
6246 relinfo.symtab = symtab;
6247 relinfo.layout = layout;
6248 relinfo.object = this;
6249
6250 // Do relocation stubs scanning.
6251 const unsigned char* p = pshdrs + shdr_size;
6252 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6253 {
6254 const elfcpp::Shdr<32, big_endian> shdr(p);
6255 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
6256 pshdrs))
6257 {
6258 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
6259 Arm_address output_offset = this->get_output_section_offset(index);
6260 Arm_address output_address;
6261 if (output_offset != invalid_address)
6262 output_address = out_sections[index]->address() + output_offset;
6263 else
6264 {
6265 // Currently this only happens for a relaxed section.
6266 const Output_relaxed_input_section* poris =
6267 out_sections[index]->find_relaxed_input_section(this, index);
6268 gold_assert(poris != NULL);
6269 output_address = poris->address();
6270 }
6271
6272 // Get the relocations.
6273 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
6274 shdr.get_sh_size(),
6275 true, false);
6276
6277 // Get the section contents. This does work for the case in which
6278 // we modify the contents of an input section. We need to pass the
6279 // output view under such circumstances.
6280 section_size_type input_view_size = 0;
6281 const unsigned char* input_view =
6282 this->section_contents(index, &input_view_size, false);
6283
6284 relinfo.reloc_shndx = i;
6285 relinfo.data_shndx = index;
6286 unsigned int sh_type = shdr.get_sh_type();
6287 unsigned int reloc_size;
6288 if (sh_type == elfcpp::SHT_REL)
6289 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6290 else
6291 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6292
6293 Output_section* os = out_sections[index];
6294 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
6295 shdr.get_sh_size() / reloc_size,
6296 os,
6297 output_offset == invalid_address,
6298 input_view, output_address,
6299 input_view_size);
6300 }
6301 }
6302
6303 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
6304 // after its relocation section, if there is one, is processed for
6305 // relocation stubs. Merging this loop with the one above would have been
6306 // complicated since we would have had to make sure that relocation stub
6307 // scanning is done first.
6308 if (arm_target->fix_cortex_a8())
6309 {
6310 const unsigned char* p = pshdrs + shdr_size;
6311 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6312 {
6313 const elfcpp::Shdr<32, big_endian> shdr(p);
6314 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
6315 out_sections[i],
6316 symtab))
6317 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
6318 arm_target);
6319 }
6320 }
6321
6322 // After we've done the relocations, we release the hash tables,
6323 // since we no longer need them.
6324 this->free_input_to_output_maps();
6325 }
6326
6327 // Count the local symbols. The ARM backend needs to know if a symbol
6328 // is a THUMB function or not. For global symbols, it is easy because
6329 // the Symbol object keeps the ELF symbol type. For local symbol it is
6330 // harder because we cannot access this information. So we override the
6331 // do_count_local_symbol in parent and scan local symbols to mark
6332 // THUMB functions. This is not the most efficient way but I do not want to
6333 // slow down other ports by calling a per symbol target hook inside
6334 // Sized_relobj_file<size, big_endian>::do_count_local_symbols.
6335
6336 template<bool big_endian>
6337 void
6338 Arm_relobj<big_endian>::do_count_local_symbols(
6339 Stringpool_template<char>* pool,
6340 Stringpool_template<char>* dynpool)
6341 {
6342 // We need to fix-up the values of any local symbols whose type are
6343 // STT_ARM_TFUNC.
6344
6345 // Ask parent to count the local symbols.
6346 Sized_relobj_file<32, big_endian>::do_count_local_symbols(pool, dynpool);
6347 const unsigned int loccount = this->local_symbol_count();
6348 if (loccount == 0)
6349 return;
6350
6351 // Initialize the thumb function bit-vector.
6352 std::vector<bool> empty_vector(loccount, false);
6353 this->local_symbol_is_thumb_function_.swap(empty_vector);
6354
6355 // Read the symbol table section header.
6356 const unsigned int symtab_shndx = this->symtab_shndx();
6357 elfcpp::Shdr<32, big_endian>
6358 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6359 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6360
6361 // Read the local symbols.
6362 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6363 gold_assert(loccount == symtabshdr.get_sh_info());
6364 off_t locsize = loccount * sym_size;
6365 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6366 locsize, true, true);
6367
6368 // For mapping symbol processing, we need to read the symbol names.
6369 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6370 if (strtab_shndx >= this->shnum())
6371 {
6372 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6373 return;
6374 }
6375
6376 elfcpp::Shdr<32, big_endian>
6377 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6378 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6379 {
6380 this->error(_("symbol table name section has wrong type: %u"),
6381 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6382 return;
6383 }
6384 const char* pnames =
6385 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6386 strtabshdr.get_sh_size(),
6387 false, false));
6388
6389 // Loop over the local symbols and mark any local symbols pointing
6390 // to THUMB functions.
6391
6392 // Skip the first dummy symbol.
6393 psyms += sym_size;
6394 typename Sized_relobj_file<32, big_endian>::Local_values* plocal_values =
6395 this->local_values();
6396 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6397 {
6398 elfcpp::Sym<32, big_endian> sym(psyms);
6399 elfcpp::STT st_type = sym.get_st_type();
6400 Symbol_value<32>& lv((*plocal_values)[i]);
6401 Arm_address input_value = lv.input_value();
6402
6403 // Check to see if this is a mapping symbol.
6404 const char* sym_name = pnames + sym.get_st_name();
6405 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6406 {
6407 bool is_ordinary;
6408 unsigned int input_shndx =
6409 this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
6410 gold_assert(is_ordinary);
6411
6412 // Strip of LSB in case this is a THUMB symbol.
6413 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6414 this->mapping_symbols_info_[msp] = sym_name[1];
6415 }
6416
6417 if (st_type == elfcpp::STT_ARM_TFUNC
6418 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6419 {
6420 // This is a THUMB function. Mark this and canonicalize the
6421 // symbol value by setting LSB.
6422 this->local_symbol_is_thumb_function_[i] = true;
6423 if ((input_value & 1) == 0)
6424 lv.set_input_value(input_value | 1);
6425 }
6426 }
6427 }
6428
6429 // Relocate sections.
6430 template<bool big_endian>
6431 void
6432 Arm_relobj<big_endian>::do_relocate_sections(
6433 const Symbol_table* symtab,
6434 const Layout* layout,
6435 const unsigned char* pshdrs,
6436 Output_file* of,
6437 typename Sized_relobj_file<32, big_endian>::Views* pviews)
6438 {
6439 // Call parent to relocate sections.
6440 Sized_relobj_file<32, big_endian>::do_relocate_sections(symtab, layout,
6441 pshdrs, of, pviews);
6442
6443 // We do not generate stubs if doing a relocatable link.
6444 if (parameters->options().relocatable())
6445 return;
6446
6447 // Relocate stub tables.
6448 unsigned int shnum = this->shnum();
6449
6450 Target_arm<big_endian>* arm_target =
6451 Target_arm<big_endian>::default_target();
6452
6453 Relocate_info<32, big_endian> relinfo;
6454 relinfo.symtab = symtab;
6455 relinfo.layout = layout;
6456 relinfo.object = this;
6457
6458 for (unsigned int i = 1; i < shnum; ++i)
6459 {
6460 Arm_input_section<big_endian>* arm_input_section =
6461 arm_target->find_arm_input_section(this, i);
6462
6463 if (arm_input_section != NULL
6464 && arm_input_section->is_stub_table_owner()
6465 && !arm_input_section->stub_table()->empty())
6466 {
6467 // We cannot discard a section if it owns a stub table.
6468 Output_section* os = this->output_section(i);
6469 gold_assert(os != NULL);
6470
6471 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6472 relinfo.reloc_shdr = NULL;
6473 relinfo.data_shndx = i;
6474 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6475
6476 gold_assert((*pviews)[i].view != NULL);
6477
6478 // We are passed the output section view. Adjust it to cover the
6479 // stub table only.
6480 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6481 gold_assert((stub_table->address() >= (*pviews)[i].address)
6482 && ((stub_table->address() + stub_table->data_size())
6483 <= (*pviews)[i].address + (*pviews)[i].view_size));
6484
6485 off_t offset = stub_table->address() - (*pviews)[i].address;
6486 unsigned char* view = (*pviews)[i].view + offset;
6487 Arm_address address = stub_table->address();
6488 section_size_type view_size = stub_table->data_size();
6489
6490 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6491 view_size);
6492 }
6493
6494 // Apply Cortex A8 workaround if applicable.
6495 if (this->section_has_cortex_a8_workaround(i))
6496 {
6497 unsigned char* view = (*pviews)[i].view;
6498 Arm_address view_address = (*pviews)[i].address;
6499 section_size_type view_size = (*pviews)[i].view_size;
6500 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6501
6502 // Adjust view to cover section.
6503 Output_section* os = this->output_section(i);
6504 gold_assert(os != NULL);
6505 Arm_address section_address =
6506 this->simple_input_section_output_address(i, os);
6507 uint64_t section_size = this->section_size(i);
6508
6509 gold_assert(section_address >= view_address
6510 && ((section_address + section_size)
6511 <= (view_address + view_size)));
6512
6513 unsigned char* section_view = view + (section_address - view_address);
6514
6515 // Apply the Cortex-A8 workaround to the output address range
6516 // corresponding to this input section.
6517 stub_table->apply_cortex_a8_workaround_to_address_range(
6518 arm_target,
6519 section_view,
6520 section_address,
6521 section_size);
6522 }
6523 }
6524 }
6525
6526 // Find the linked text section of an EXIDX section by looking at the first
6527 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6528 // must be linked to its associated code section via the sh_link field of
6529 // its section header. However, some tools are broken and the link is not
6530 // always set. LD just drops such an EXIDX section silently, causing the
6531 // associated code not unwindabled. Here we try a little bit harder to
6532 // discover the linked code section.
6533 //
6534 // PSHDR points to the section header of a relocation section of an EXIDX
6535 // section. If we can find a linked text section, return true and
6536 // store the text section index in the location PSHNDX. Otherwise
6537 // return false.
6538
6539 template<bool big_endian>
6540 bool
6541 Arm_relobj<big_endian>::find_linked_text_section(
6542 const unsigned char* pshdr,
6543 const unsigned char* psyms,
6544 unsigned int* pshndx)
6545 {
6546 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6547
6548 // If there is no relocation, we cannot find the linked text section.
6549 size_t reloc_size;
6550 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6551 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6552 else
6553 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6554 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6555
6556 // Get the relocations.
6557 const unsigned char* prelocs =
6558 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6559
6560 // Find the REL31 relocation for the first word of the first EXIDX entry.
6561 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6562 {
6563 Arm_address r_offset;
6564 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6565 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6566 {
6567 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6568 r_info = reloc.get_r_info();
6569 r_offset = reloc.get_r_offset();
6570 }
6571 else
6572 {
6573 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6574 r_info = reloc.get_r_info();
6575 r_offset = reloc.get_r_offset();
6576 }
6577
6578 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6579 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6580 continue;
6581
6582 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6583 if (r_sym == 0
6584 || r_sym >= this->local_symbol_count()
6585 || r_offset != 0)
6586 continue;
6587
6588 // This is the relocation for the first word of the first EXIDX entry.
6589 // We expect to see a local section symbol.
6590 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6591 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6592 if (sym.get_st_type() == elfcpp::STT_SECTION)
6593 {
6594 bool is_ordinary;
6595 *pshndx =
6596 this->adjust_sym_shndx(r_sym, sym.get_st_shndx(), &is_ordinary);
6597 gold_assert(is_ordinary);
6598 return true;
6599 }
6600 else
6601 return false;
6602 }
6603
6604 return false;
6605 }
6606
6607 // Make an EXIDX input section object for an EXIDX section whose index is
6608 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6609 // is the section index of the linked text section.
6610
6611 template<bool big_endian>
6612 void
6613 Arm_relobj<big_endian>::make_exidx_input_section(
6614 unsigned int shndx,
6615 const elfcpp::Shdr<32, big_endian>& shdr,
6616 unsigned int text_shndx,
6617 const elfcpp::Shdr<32, big_endian>& text_shdr)
6618 {
6619 // Create an Arm_exidx_input_section object for this EXIDX section.
6620 Arm_exidx_input_section* exidx_input_section =
6621 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6622 shdr.get_sh_addralign(),
6623 text_shdr.get_sh_size());
6624
6625 gold_assert(this->exidx_section_map_[shndx] == NULL);
6626 this->exidx_section_map_[shndx] = exidx_input_section;
6627
6628 if (text_shndx == elfcpp::SHN_UNDEF || text_shndx >= this->shnum())
6629 {
6630 gold_error(_("EXIDX section %s(%u) links to invalid section %u in %s"),
6631 this->section_name(shndx).c_str(), shndx, text_shndx,
6632 this->name().c_str());
6633 exidx_input_section->set_has_errors();
6634 }
6635 else if (this->exidx_section_map_[text_shndx] != NULL)
6636 {
6637 unsigned other_exidx_shndx =
6638 this->exidx_section_map_[text_shndx]->shndx();
6639 gold_error(_("EXIDX sections %s(%u) and %s(%u) both link to text section"
6640 "%s(%u) in %s"),
6641 this->section_name(shndx).c_str(), shndx,
6642 this->section_name(other_exidx_shndx).c_str(),
6643 other_exidx_shndx, this->section_name(text_shndx).c_str(),
6644 text_shndx, this->name().c_str());
6645 exidx_input_section->set_has_errors();
6646 }
6647 else
6648 this->exidx_section_map_[text_shndx] = exidx_input_section;
6649
6650 // Check section flags of text section.
6651 if ((text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
6652 {
6653 gold_error(_("EXIDX section %s(%u) links to non-allocated section %s(%u) "
6654 " in %s"),
6655 this->section_name(shndx).c_str(), shndx,
6656 this->section_name(text_shndx).c_str(), text_shndx,
6657 this->name().c_str());
6658 exidx_input_section->set_has_errors();
6659 }
6660 else if ((text_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) == 0)
6661 // I would like to make this an error but currently ld just ignores
6662 // this.
6663 gold_warning(_("EXIDX section %s(%u) links to non-executable section "
6664 "%s(%u) in %s"),
6665 this->section_name(shndx).c_str(), shndx,
6666 this->section_name(text_shndx).c_str(), text_shndx,
6667 this->name().c_str());
6668 }
6669
6670 // Read the symbol information.
6671
6672 template<bool big_endian>
6673 void
6674 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6675 {
6676 // Call parent class to read symbol information.
6677 Sized_relobj_file<32, big_endian>::do_read_symbols(sd);
6678
6679 // If this input file is a binary file, it has no processor
6680 // specific flags and attributes section.
6681 Input_file::Format format = this->input_file()->format();
6682 if (format != Input_file::FORMAT_ELF)
6683 {
6684 gold_assert(format == Input_file::FORMAT_BINARY);
6685 this->merge_flags_and_attributes_ = false;
6686 return;
6687 }
6688
6689 // Read processor-specific flags in ELF file header.
6690 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6691 elfcpp::Elf_sizes<32>::ehdr_size,
6692 true, false);
6693 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6694 this->processor_specific_flags_ = ehdr.get_e_flags();
6695
6696 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6697 // sections.
6698 std::vector<unsigned int> deferred_exidx_sections;
6699 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6700 const unsigned char* pshdrs = sd->section_headers->data();
6701 const unsigned char* ps = pshdrs + shdr_size;
6702 bool must_merge_flags_and_attributes = false;
6703 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6704 {
6705 elfcpp::Shdr<32, big_endian> shdr(ps);
6706
6707 // Sometimes an object has no contents except the section name string
6708 // table and an empty symbol table with the undefined symbol. We
6709 // don't want to merge processor-specific flags from such an object.
6710 if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
6711 {
6712 // Symbol table is not empty.
6713 const elfcpp::Elf_types<32>::Elf_WXword sym_size =
6714 elfcpp::Elf_sizes<32>::sym_size;
6715 if (shdr.get_sh_size() > sym_size)
6716 must_merge_flags_and_attributes = true;
6717 }
6718 else if (shdr.get_sh_type() != elfcpp::SHT_STRTAB)
6719 // If this is neither an empty symbol table nor a string table,
6720 // be conservative.
6721 must_merge_flags_and_attributes = true;
6722
6723 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6724 {
6725 gold_assert(this->attributes_section_data_ == NULL);
6726 section_offset_type section_offset = shdr.get_sh_offset();
6727 section_size_type section_size =
6728 convert_to_section_size_type(shdr.get_sh_size());
6729 const unsigned char* view =
6730 this->get_view(section_offset, section_size, true, false);
6731 this->attributes_section_data_ =
6732 new Attributes_section_data(view, section_size);
6733 }
6734 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6735 {
6736 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6737 if (text_shndx == elfcpp::SHN_UNDEF)
6738 deferred_exidx_sections.push_back(i);
6739 else
6740 {
6741 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6742 + text_shndx * shdr_size);
6743 this->make_exidx_input_section(i, shdr, text_shndx, text_shdr);
6744 }
6745 // EHABI 4.4.1 requires that SHF_LINK_ORDER flag to be set.
6746 if ((shdr.get_sh_flags() & elfcpp::SHF_LINK_ORDER) == 0)
6747 gold_warning(_("SHF_LINK_ORDER not set in EXIDX section %s of %s"),
6748 this->section_name(i).c_str(), this->name().c_str());
6749 }
6750 }
6751
6752 // This is rare.
6753 if (!must_merge_flags_and_attributes)
6754 {
6755 gold_assert(deferred_exidx_sections.empty());
6756 this->merge_flags_and_attributes_ = false;
6757 return;
6758 }
6759
6760 // Some tools are broken and they do not set the link of EXIDX sections.
6761 // We look at the first relocation to figure out the linked sections.
6762 if (!deferred_exidx_sections.empty())
6763 {
6764 // We need to go over the section headers again to find the mapping
6765 // from sections being relocated to their relocation sections. This is
6766 // a bit inefficient as we could do that in the loop above. However,
6767 // we do not expect any deferred EXIDX sections normally. So we do not
6768 // want to slow down the most common path.
6769 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6770 Reloc_map reloc_map;
6771 ps = pshdrs + shdr_size;
6772 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6773 {
6774 elfcpp::Shdr<32, big_endian> shdr(ps);
6775 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6776 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6777 {
6778 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6779 if (info_shndx >= this->shnum())
6780 gold_error(_("relocation section %u has invalid info %u"),
6781 i, info_shndx);
6782 Reloc_map::value_type value(info_shndx, i);
6783 std::pair<Reloc_map::iterator, bool> result =
6784 reloc_map.insert(value);
6785 if (!result.second)
6786 gold_error(_("section %u has multiple relocation sections "
6787 "%u and %u"),
6788 info_shndx, i, reloc_map[info_shndx]);
6789 }
6790 }
6791
6792 // Read the symbol table section header.
6793 const unsigned int symtab_shndx = this->symtab_shndx();
6794 elfcpp::Shdr<32, big_endian>
6795 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6796 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6797
6798 // Read the local symbols.
6799 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6800 const unsigned int loccount = this->local_symbol_count();
6801 gold_assert(loccount == symtabshdr.get_sh_info());
6802 off_t locsize = loccount * sym_size;
6803 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6804 locsize, true, true);
6805
6806 // Process the deferred EXIDX sections.
6807 for (unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6808 {
6809 unsigned int shndx = deferred_exidx_sections[i];
6810 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6811 unsigned int text_shndx = elfcpp::SHN_UNDEF;
6812 Reloc_map::const_iterator it = reloc_map.find(shndx);
6813 if (it != reloc_map.end())
6814 find_linked_text_section(pshdrs + it->second * shdr_size,
6815 psyms, &text_shndx);
6816 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6817 + text_shndx * shdr_size);
6818 this->make_exidx_input_section(shndx, shdr, text_shndx, text_shdr);
6819 }
6820 }
6821 }
6822
6823 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6824 // sections for unwinding. These sections are referenced implicitly by
6825 // text sections linked in the section headers. If we ignore these implicit
6826 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6827 // will be garbage-collected incorrectly. Hence we override the same function
6828 // in the base class to handle these implicit references.
6829
6830 template<bool big_endian>
6831 void
6832 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6833 Layout* layout,
6834 Read_relocs_data* rd)
6835 {
6836 // First, call base class method to process relocations in this object.
6837 Sized_relobj_file<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6838
6839 // If --gc-sections is not specified, there is nothing more to do.
6840 // This happens when --icf is used but --gc-sections is not.
6841 if (!parameters->options().gc_sections())
6842 return;
6843
6844 unsigned int shnum = this->shnum();
6845 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6846 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6847 shnum * shdr_size,
6848 true, true);
6849
6850 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6851 // to these from the linked text sections.
6852 const unsigned char* ps = pshdrs + shdr_size;
6853 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6854 {
6855 elfcpp::Shdr<32, big_endian> shdr(ps);
6856 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6857 {
6858 // Found an .ARM.exidx section, add it to the set of reachable
6859 // sections from its linked text section.
6860 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6861 symtab->gc()->add_reference(this, text_shndx, this, i);
6862 }
6863 }
6864 }
6865
6866 // Update output local symbol count. Owing to EXIDX entry merging, some local
6867 // symbols will be removed in output. Adjust output local symbol count
6868 // accordingly. We can only changed the static output local symbol count. It
6869 // is too late to change the dynamic symbols.
6870
6871 template<bool big_endian>
6872 void
6873 Arm_relobj<big_endian>::update_output_local_symbol_count()
6874 {
6875 // Caller should check that this needs updating. We want caller checking
6876 // because output_local_symbol_count_needs_update() is most likely inlined.
6877 gold_assert(this->output_local_symbol_count_needs_update_);
6878
6879 gold_assert(this->symtab_shndx() != -1U);
6880 if (this->symtab_shndx() == 0)
6881 {
6882 // This object has no symbols. Weird but legal.
6883 return;
6884 }
6885
6886 // Read the symbol table section header.
6887 const unsigned int symtab_shndx = this->symtab_shndx();
6888 elfcpp::Shdr<32, big_endian>
6889 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6890 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6891
6892 // Read the local symbols.
6893 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6894 const unsigned int loccount = this->local_symbol_count();
6895 gold_assert(loccount == symtabshdr.get_sh_info());
6896 off_t locsize = loccount * sym_size;
6897 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6898 locsize, true, true);
6899
6900 // Loop over the local symbols.
6901
6902 typedef typename Sized_relobj_file<32, big_endian>::Output_sections
6903 Output_sections;
6904 const Output_sections& out_sections(this->output_sections());
6905 unsigned int shnum = this->shnum();
6906 unsigned int count = 0;
6907 // Skip the first, dummy, symbol.
6908 psyms += sym_size;
6909 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6910 {
6911 elfcpp::Sym<32, big_endian> sym(psyms);
6912
6913 Symbol_value<32>& lv((*this->local_values())[i]);
6914
6915 // This local symbol was already discarded by do_count_local_symbols.
6916 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6917 continue;
6918
6919 bool is_ordinary;
6920 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6921 &is_ordinary);
6922
6923 if (shndx < shnum)
6924 {
6925 Output_section* os = out_sections[shndx];
6926
6927 // This local symbol no longer has an output section. Discard it.
6928 if (os == NULL)
6929 {
6930 lv.set_no_output_symtab_entry();
6931 continue;
6932 }
6933
6934 // Currently we only discard parts of EXIDX input sections.
6935 // We explicitly check for a merged EXIDX input section to avoid
6936 // calling Output_section_data::output_offset unless necessary.
6937 if ((this->get_output_section_offset(shndx) == invalid_address)
6938 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6939 {
6940 section_offset_type output_offset =
6941 os->output_offset(this, shndx, lv.input_value());
6942 if (output_offset == -1)
6943 {
6944 // This symbol is defined in a part of an EXIDX input section
6945 // that is discarded due to entry merging.
6946 lv.set_no_output_symtab_entry();
6947 continue;
6948 }
6949 }
6950 }
6951
6952 ++count;
6953 }
6954
6955 this->set_output_local_symbol_count(count);
6956 this->output_local_symbol_count_needs_update_ = false;
6957 }
6958
6959 // Arm_dynobj methods.
6960
6961 // Read the symbol information.
6962
6963 template<bool big_endian>
6964 void
6965 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6966 {
6967 // Call parent class to read symbol information.
6968 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6969
6970 // Read processor-specific flags in ELF file header.
6971 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6972 elfcpp::Elf_sizes<32>::ehdr_size,
6973 true, false);
6974 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6975 this->processor_specific_flags_ = ehdr.get_e_flags();
6976
6977 // Read the attributes section if there is one.
6978 // We read from the end because gas seems to put it near the end of
6979 // the section headers.
6980 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6981 const unsigned char* ps =
6982 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6983 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6984 {
6985 elfcpp::Shdr<32, big_endian> shdr(ps);
6986 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6987 {
6988 section_offset_type section_offset = shdr.get_sh_offset();
6989 section_size_type section_size =
6990 convert_to_section_size_type(shdr.get_sh_size());
6991 const unsigned char* view =
6992 this->get_view(section_offset, section_size, true, false);
6993 this->attributes_section_data_ =
6994 new Attributes_section_data(view, section_size);
6995 break;
6996 }
6997 }
6998 }
6999
7000 // Stub_addend_reader methods.
7001
7002 // Read the addend of a REL relocation of type R_TYPE at VIEW.
7003
7004 template<bool big_endian>
7005 elfcpp::Elf_types<32>::Elf_Swxword
7006 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
7007 unsigned int r_type,
7008 const unsigned char* view,
7009 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
7010 {
7011 typedef class Arm_relocate_functions<big_endian> RelocFuncs;
7012
7013 switch (r_type)
7014 {
7015 case elfcpp::R_ARM_CALL:
7016 case elfcpp::R_ARM_JUMP24:
7017 case elfcpp::R_ARM_PLT32:
7018 {
7019 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
7020 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
7021 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
7022 return Bits<26>::sign_extend32(val << 2);
7023 }
7024
7025 case elfcpp::R_ARM_THM_CALL:
7026 case elfcpp::R_ARM_THM_JUMP24:
7027 case elfcpp::R_ARM_THM_XPC22:
7028 {
7029 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
7030 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
7031 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
7032 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
7033 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
7034 }
7035
7036 case elfcpp::R_ARM_THM_JUMP19:
7037 {
7038 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
7039 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
7040 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
7041 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
7042 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
7043 }
7044
7045 default:
7046 gold_unreachable();
7047 }
7048 }
7049
7050 // Arm_output_data_got methods.
7051
7052 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
7053 // The first one is initialized to be 1, which is the module index for
7054 // the main executable and the second one 0. A reloc of the type
7055 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
7056 // be applied by gold. GSYM is a global symbol.
7057 //
7058 template<bool big_endian>
7059 void
7060 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
7061 unsigned int got_type,
7062 Symbol* gsym)
7063 {
7064 if (gsym->has_got_offset(got_type))
7065 return;
7066
7067 // We are doing a static link. Just mark it as belong to module 1,
7068 // the executable.
7069 unsigned int got_offset = this->add_constant(1);
7070 gsym->set_got_offset(got_type, got_offset);
7071 got_offset = this->add_constant(0);
7072 this->static_relocs_.push_back(Static_reloc(got_offset,
7073 elfcpp::R_ARM_TLS_DTPOFF32,
7074 gsym));
7075 }
7076
7077 // Same as the above but for a local symbol.
7078
7079 template<bool big_endian>
7080 void
7081 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
7082 unsigned int got_type,
7083 Sized_relobj_file<32, big_endian>* object,
7084 unsigned int index)
7085 {
7086 if (object->local_has_got_offset(index, got_type))
7087 return;
7088
7089 // We are doing a static link. Just mark it as belong to module 1,
7090 // the executable.
7091 unsigned int got_offset = this->add_constant(1);
7092 object->set_local_got_offset(index, got_type, got_offset);
7093 got_offset = this->add_constant(0);
7094 this->static_relocs_.push_back(Static_reloc(got_offset,
7095 elfcpp::R_ARM_TLS_DTPOFF32,
7096 object, index));
7097 }
7098
7099 template<bool big_endian>
7100 void
7101 Arm_output_data_got<big_endian>::do_write(Output_file* of)
7102 {
7103 // Call parent to write out GOT.
7104 Output_data_got<32, big_endian>::do_write(of);
7105
7106 // We are done if there is no fix up.
7107 if (this->static_relocs_.empty())
7108 return;
7109
7110 gold_assert(parameters->doing_static_link());
7111
7112 const off_t offset = this->offset();
7113 const section_size_type oview_size =
7114 convert_to_section_size_type(this->data_size());
7115 unsigned char* const oview = of->get_output_view(offset, oview_size);
7116
7117 Output_segment* tls_segment = this->layout_->tls_segment();
7118 gold_assert(tls_segment != NULL);
7119
7120 // The thread pointer $tp points to the TCB, which is followed by the
7121 // TLS. So we need to adjust $tp relative addressing by this amount.
7122 Arm_address aligned_tcb_size =
7123 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
7124
7125 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
7126 {
7127 Static_reloc& reloc(this->static_relocs_[i]);
7128
7129 Arm_address value;
7130 if (!reloc.symbol_is_global())
7131 {
7132 Sized_relobj_file<32, big_endian>* object = reloc.relobj();
7133 const Symbol_value<32>* psymval =
7134 reloc.relobj()->local_symbol(reloc.index());
7135
7136 // We are doing static linking. Issue an error and skip this
7137 // relocation if the symbol is undefined or in a discarded_section.
7138 bool is_ordinary;
7139 unsigned int shndx = psymval->input_shndx(&is_ordinary);
7140 if ((shndx == elfcpp::SHN_UNDEF)
7141 || (is_ordinary
7142 && shndx != elfcpp::SHN_UNDEF
7143 && !object->is_section_included(shndx)
7144 && !this->symbol_table_->is_section_folded(object, shndx)))
7145 {
7146 gold_error(_("undefined or discarded local symbol %u from "
7147 " object %s in GOT"),
7148 reloc.index(), reloc.relobj()->name().c_str());
7149 continue;
7150 }
7151
7152 value = psymval->value(object, 0);
7153 }
7154 else
7155 {
7156 const Symbol* gsym = reloc.symbol();
7157 gold_assert(gsym != NULL);
7158 if (gsym->is_forwarder())
7159 gsym = this->symbol_table_->resolve_forwards(gsym);
7160
7161 // We are doing static linking. Issue an error and skip this
7162 // relocation if the symbol is undefined or in a discarded_section
7163 // unless it is a weakly_undefined symbol.
7164 if ((gsym->is_defined_in_discarded_section()
7165 || gsym->is_undefined())
7166 && !gsym->is_weak_undefined())
7167 {
7168 gold_error(_("undefined or discarded symbol %s in GOT"),
7169 gsym->name());
7170 continue;
7171 }
7172
7173 if (!gsym->is_weak_undefined())
7174 {
7175 const Sized_symbol<32>* sym =
7176 static_cast<const Sized_symbol<32>*>(gsym);
7177 value = sym->value();
7178 }
7179 else
7180 value = 0;
7181 }
7182
7183 unsigned got_offset = reloc.got_offset();
7184 gold_assert(got_offset < oview_size);
7185
7186 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
7187 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
7188 Valtype x;
7189 switch (reloc.r_type())
7190 {
7191 case elfcpp::R_ARM_TLS_DTPOFF32:
7192 x = value;
7193 break;
7194 case elfcpp::R_ARM_TLS_TPOFF32:
7195 x = value + aligned_tcb_size;
7196 break;
7197 default:
7198 gold_unreachable();
7199 }
7200 elfcpp::Swap<32, big_endian>::writeval(wv, x);
7201 }
7202
7203 of->write_output_view(offset, oview_size, oview);
7204 }
7205
7206 // A class to handle the PLT data.
7207 // This is an abstract base class that handles most of the linker details
7208 // but does not know the actual contents of PLT entries. The derived
7209 // classes below fill in those details.
7210
7211 template<bool big_endian>
7212 class Output_data_plt_arm : public Output_section_data
7213 {
7214 public:
7215 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
7216 Reloc_section;
7217
7218 Output_data_plt_arm(Layout*, uint64_t addralign, Output_data_space*);
7219
7220 // Add an entry to the PLT.
7221 void
7222 add_entry(Symbol* gsym);
7223
7224 // Return the .rel.plt section data.
7225 const Reloc_section*
7226 rel_plt() const
7227 { return this->rel_; }
7228
7229 // Return the number of PLT entries.
7230 unsigned int
7231 entry_count() const
7232 { return this->count_; }
7233
7234 // Return the offset of the first non-reserved PLT entry.
7235 unsigned int
7236 first_plt_entry_offset() const
7237 { return this->do_first_plt_entry_offset(); }
7238
7239 // Return the size of a PLT entry.
7240 unsigned int
7241 get_plt_entry_size() const
7242 { return this->do_get_plt_entry_size(); }
7243
7244 protected:
7245 // Fill in the first PLT entry.
7246 void
7247 fill_first_plt_entry(unsigned char* pov,
7248 Arm_address got_address,
7249 Arm_address plt_address)
7250 { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
7251
7252 void
7253 fill_plt_entry(unsigned char* pov,
7254 Arm_address got_address,
7255 Arm_address plt_address,
7256 unsigned int got_offset,
7257 unsigned int plt_offset)
7258 { do_fill_plt_entry(pov, got_address, plt_address, got_offset, plt_offset); }
7259
7260 virtual unsigned int
7261 do_first_plt_entry_offset() const = 0;
7262
7263 virtual unsigned int
7264 do_get_plt_entry_size() const = 0;
7265
7266 virtual void
7267 do_fill_first_plt_entry(unsigned char* pov,
7268 Arm_address got_address,
7269 Arm_address plt_address) = 0;
7270
7271 virtual void
7272 do_fill_plt_entry(unsigned char* pov,
7273 Arm_address got_address,
7274 Arm_address plt_address,
7275 unsigned int got_offset,
7276 unsigned int plt_offset) = 0;
7277
7278 void
7279 do_adjust_output_section(Output_section* os);
7280
7281 // Write to a map file.
7282 void
7283 do_print_to_mapfile(Mapfile* mapfile) const
7284 { mapfile->print_output_data(this, _("** PLT")); }
7285
7286 private:
7287 // Set the final size.
7288 void
7289 set_final_data_size()
7290 {
7291 this->set_data_size(this->first_plt_entry_offset()
7292 + this->count_ * this->get_plt_entry_size());
7293 }
7294
7295 // Write out the PLT data.
7296 void
7297 do_write(Output_file*);
7298
7299 // The reloc section.
7300 Reloc_section* rel_;
7301 // The .got.plt section.
7302 Output_data_space* got_plt_;
7303 // The number of PLT entries.
7304 unsigned int count_;
7305 };
7306
7307 // Create the PLT section. The ordinary .got section is an argument,
7308 // since we need to refer to the start. We also create our own .got
7309 // section just for PLT entries.
7310
7311 template<bool big_endian>
7312 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
7313 uint64_t addralign,
7314 Output_data_space* got_plt)
7315 : Output_section_data(addralign), got_plt_(got_plt), count_(0)
7316 {
7317 this->rel_ = new Reloc_section(false);
7318 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
7319 elfcpp::SHF_ALLOC, this->rel_,
7320 ORDER_DYNAMIC_PLT_RELOCS, false);
7321 }
7322
7323 template<bool big_endian>
7324 void
7325 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
7326 {
7327 os->set_entsize(0);
7328 }
7329
7330 // Add an entry to the PLT.
7331
7332 template<bool big_endian>
7333 void
7334 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
7335 {
7336 gold_assert(!gsym->has_plt_offset());
7337
7338 // Note that when setting the PLT offset we skip the initial
7339 // reserved PLT entry.
7340 gsym->set_plt_offset((this->count_) * this->get_plt_entry_size()
7341 + this->first_plt_entry_offset());
7342
7343 ++this->count_;
7344
7345 section_offset_type got_offset = this->got_plt_->current_data_size();
7346
7347 // Every PLT entry needs a GOT entry which points back to the PLT
7348 // entry (this will be changed by the dynamic linker, normally
7349 // lazily when the function is called).
7350 this->got_plt_->set_current_data_size(got_offset + 4);
7351
7352 // Every PLT entry needs a reloc.
7353 gsym->set_needs_dynsym_entry();
7354 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
7355 got_offset);
7356
7357 // Note that we don't need to save the symbol. The contents of the
7358 // PLT are independent of which symbols are used. The symbols only
7359 // appear in the relocations.
7360 }
7361
7362 template<bool big_endian>
7363 class Output_data_plt_arm_standard : public Output_data_plt_arm<big_endian>
7364 {
7365 public:
7366 Output_data_plt_arm_standard(Layout* layout, Output_data_space* got_plt)
7367 : Output_data_plt_arm<big_endian>(layout, 4, got_plt)
7368 { }
7369
7370 protected:
7371 // Return the offset of the first non-reserved PLT entry.
7372 virtual unsigned int
7373 do_first_plt_entry_offset() const
7374 { return sizeof(first_plt_entry); }
7375
7376 // Return the size of a PLT entry.
7377 virtual unsigned int
7378 do_get_plt_entry_size() const
7379 { return sizeof(plt_entry); }
7380
7381 virtual void
7382 do_fill_first_plt_entry(unsigned char* pov,
7383 Arm_address got_address,
7384 Arm_address plt_address);
7385
7386 virtual void
7387 do_fill_plt_entry(unsigned char* pov,
7388 Arm_address got_address,
7389 Arm_address plt_address,
7390 unsigned int got_offset,
7391 unsigned int plt_offset);
7392
7393 private:
7394 // Template for the first PLT entry.
7395 static const uint32_t first_plt_entry[5];
7396
7397 // Template for subsequent PLT entries.
7398 static const uint32_t plt_entry[3];
7399 };
7400
7401 // ARM PLTs.
7402 // FIXME: This is not very flexible. Right now this has only been tested
7403 // on armv5te. If we are to support additional architecture features like
7404 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
7405
7406 // The first entry in the PLT.
7407 template<bool big_endian>
7408 const uint32_t Output_data_plt_arm_standard<big_endian>::first_plt_entry[5] =
7409 {
7410 0xe52de004, // str lr, [sp, #-4]!
7411 0xe59fe004, // ldr lr, [pc, #4]
7412 0xe08fe00e, // add lr, pc, lr
7413 0xe5bef008, // ldr pc, [lr, #8]!
7414 0x00000000, // &GOT[0] - .
7415 };
7416
7417 template<bool big_endian>
7418 void
7419 Output_data_plt_arm_standard<big_endian>::do_fill_first_plt_entry(
7420 unsigned char* pov,
7421 Arm_address got_address,
7422 Arm_address plt_address)
7423 {
7424 // Write first PLT entry. All but the last word are constants.
7425 const size_t num_first_plt_words = (sizeof(first_plt_entry)
7426 / sizeof(plt_entry[0]));
7427 for (size_t i = 0; i < num_first_plt_words - 1; i++)
7428 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
7429 // Last word in first PLT entry is &GOT[0] - .
7430 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
7431 got_address - (plt_address + 16));
7432 }
7433
7434 // Subsequent entries in the PLT.
7435
7436 template<bool big_endian>
7437 const uint32_t Output_data_plt_arm_standard<big_endian>::plt_entry[3] =
7438 {
7439 0xe28fc600, // add ip, pc, #0xNN00000
7440 0xe28cca00, // add ip, ip, #0xNN000
7441 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
7442 };
7443
7444 template<bool big_endian>
7445 void
7446 Output_data_plt_arm_standard<big_endian>::do_fill_plt_entry(
7447 unsigned char* pov,
7448 Arm_address got_address,
7449 Arm_address plt_address,
7450 unsigned int got_offset,
7451 unsigned int plt_offset)
7452 {
7453 int32_t offset = ((got_address + got_offset)
7454 - (plt_address + plt_offset + 8));
7455
7456 gold_assert(offset >= 0 && offset < 0x0fffffff);
7457 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
7458 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
7459 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
7460 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
7461 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
7462 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7463 }
7464
7465 // Write out the PLT. This uses the hand-coded instructions above,
7466 // and adjusts them as needed. This is all specified by the arm ELF
7467 // Processor Supplement.
7468
7469 template<bool big_endian>
7470 void
7471 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
7472 {
7473 const off_t offset = this->offset();
7474 const section_size_type oview_size =
7475 convert_to_section_size_type(this->data_size());
7476 unsigned char* const oview = of->get_output_view(offset, oview_size);
7477
7478 const off_t got_file_offset = this->got_plt_->offset();
7479 const section_size_type got_size =
7480 convert_to_section_size_type(this->got_plt_->data_size());
7481 unsigned char* const got_view = of->get_output_view(got_file_offset,
7482 got_size);
7483 unsigned char* pov = oview;
7484
7485 Arm_address plt_address = this->address();
7486 Arm_address got_address = this->got_plt_->address();
7487
7488 // Write first PLT entry.
7489 this->fill_first_plt_entry(pov, got_address, plt_address);
7490 pov += this->first_plt_entry_offset();
7491
7492 unsigned char* got_pov = got_view;
7493
7494 memset(got_pov, 0, 12);
7495 got_pov += 12;
7496
7497 unsigned int plt_offset = this->first_plt_entry_offset();
7498 unsigned int got_offset = 12;
7499 const unsigned int count = this->count_;
7500 for (unsigned int i = 0;
7501 i < count;
7502 ++i,
7503 pov += this->get_plt_entry_size(),
7504 got_pov += 4,
7505 plt_offset += this->get_plt_entry_size(),
7506 got_offset += 4)
7507 {
7508 // Set and adjust the PLT entry itself.
7509 this->fill_plt_entry(pov, got_address, plt_address,
7510 got_offset, plt_offset);
7511
7512 // Set the entry in the GOT.
7513 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7514 }
7515
7516 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7517 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7518
7519 of->write_output_view(offset, oview_size, oview);
7520 of->write_output_view(got_file_offset, got_size, got_view);
7521 }
7522
7523 // Create a PLT entry for a global symbol.
7524
7525 template<bool big_endian>
7526 void
7527 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7528 Symbol* gsym)
7529 {
7530 if (gsym->has_plt_offset())
7531 return;
7532
7533 if (this->plt_ == NULL)
7534 {
7535 // Create the GOT sections first.
7536 this->got_section(symtab, layout);
7537
7538 this->plt_ = this->make_data_plt(layout, this->got_plt_);
7539
7540 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7541 (elfcpp::SHF_ALLOC
7542 | elfcpp::SHF_EXECINSTR),
7543 this->plt_, ORDER_PLT, false);
7544 }
7545 this->plt_->add_entry(gsym);
7546 }
7547
7548 // Return the number of entries in the PLT.
7549
7550 template<bool big_endian>
7551 unsigned int
7552 Target_arm<big_endian>::plt_entry_count() const
7553 {
7554 if (this->plt_ == NULL)
7555 return 0;
7556 return this->plt_->entry_count();
7557 }
7558
7559 // Return the offset of the first non-reserved PLT entry.
7560
7561 template<bool big_endian>
7562 unsigned int
7563 Target_arm<big_endian>::first_plt_entry_offset() const
7564 {
7565 return this->plt_->first_plt_entry_offset();
7566 }
7567
7568 // Return the size of each PLT entry.
7569
7570 template<bool big_endian>
7571 unsigned int
7572 Target_arm<big_endian>::plt_entry_size() const
7573 {
7574 return this->plt_->get_plt_entry_size();
7575 }
7576
7577 // Get the section to use for TLS_DESC relocations.
7578
7579 template<bool big_endian>
7580 typename Target_arm<big_endian>::Reloc_section*
7581 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7582 {
7583 return this->plt_section()->rel_tls_desc(layout);
7584 }
7585
7586 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7587
7588 template<bool big_endian>
7589 void
7590 Target_arm<big_endian>::define_tls_base_symbol(
7591 Symbol_table* symtab,
7592 Layout* layout)
7593 {
7594 if (this->tls_base_symbol_defined_)
7595 return;
7596
7597 Output_segment* tls_segment = layout->tls_segment();
7598 if (tls_segment != NULL)
7599 {
7600 bool is_exec = parameters->options().output_is_executable();
7601 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7602 Symbol_table::PREDEFINED,
7603 tls_segment, 0, 0,
7604 elfcpp::STT_TLS,
7605 elfcpp::STB_LOCAL,
7606 elfcpp::STV_HIDDEN, 0,
7607 (is_exec
7608 ? Symbol::SEGMENT_END
7609 : Symbol::SEGMENT_START),
7610 true);
7611 }
7612 this->tls_base_symbol_defined_ = true;
7613 }
7614
7615 // Create a GOT entry for the TLS module index.
7616
7617 template<bool big_endian>
7618 unsigned int
7619 Target_arm<big_endian>::got_mod_index_entry(
7620 Symbol_table* symtab,
7621 Layout* layout,
7622 Sized_relobj_file<32, big_endian>* object)
7623 {
7624 if (this->got_mod_index_offset_ == -1U)
7625 {
7626 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7627 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7628 unsigned int got_offset;
7629 if (!parameters->doing_static_link())
7630 {
7631 got_offset = got->add_constant(0);
7632 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7633 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7634 got_offset);
7635 }
7636 else
7637 {
7638 // We are doing a static link. Just mark it as belong to module 1,
7639 // the executable.
7640 got_offset = got->add_constant(1);
7641 }
7642
7643 got->add_constant(0);
7644 this->got_mod_index_offset_ = got_offset;
7645 }
7646 return this->got_mod_index_offset_;
7647 }
7648
7649 // Optimize the TLS relocation type based on what we know about the
7650 // symbol. IS_FINAL is true if the final address of this symbol is
7651 // known at link time.
7652
7653 template<bool big_endian>
7654 tls::Tls_optimization
7655 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7656 {
7657 // FIXME: Currently we do not do any TLS optimization.
7658 return tls::TLSOPT_NONE;
7659 }
7660
7661 // Get the Reference_flags for a particular relocation.
7662
7663 template<bool big_endian>
7664 int
7665 Target_arm<big_endian>::Scan::get_reference_flags(unsigned int r_type)
7666 {
7667 switch (r_type)
7668 {
7669 case elfcpp::R_ARM_NONE:
7670 case elfcpp::R_ARM_V4BX:
7671 case elfcpp::R_ARM_GNU_VTENTRY:
7672 case elfcpp::R_ARM_GNU_VTINHERIT:
7673 // No symbol reference.
7674 return 0;
7675
7676 case elfcpp::R_ARM_ABS32:
7677 case elfcpp::R_ARM_ABS16:
7678 case elfcpp::R_ARM_ABS12:
7679 case elfcpp::R_ARM_THM_ABS5:
7680 case elfcpp::R_ARM_ABS8:
7681 case elfcpp::R_ARM_BASE_ABS:
7682 case elfcpp::R_ARM_MOVW_ABS_NC:
7683 case elfcpp::R_ARM_MOVT_ABS:
7684 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7685 case elfcpp::R_ARM_THM_MOVT_ABS:
7686 case elfcpp::R_ARM_ABS32_NOI:
7687 return Symbol::ABSOLUTE_REF;
7688
7689 case elfcpp::R_ARM_REL32:
7690 case elfcpp::R_ARM_LDR_PC_G0:
7691 case elfcpp::R_ARM_SBREL32:
7692 case elfcpp::R_ARM_THM_PC8:
7693 case elfcpp::R_ARM_BASE_PREL:
7694 case elfcpp::R_ARM_MOVW_PREL_NC:
7695 case elfcpp::R_ARM_MOVT_PREL:
7696 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7697 case elfcpp::R_ARM_THM_MOVT_PREL:
7698 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7699 case elfcpp::R_ARM_THM_PC12:
7700 case elfcpp::R_ARM_REL32_NOI:
7701 case elfcpp::R_ARM_ALU_PC_G0_NC:
7702 case elfcpp::R_ARM_ALU_PC_G0:
7703 case elfcpp::R_ARM_ALU_PC_G1_NC:
7704 case elfcpp::R_ARM_ALU_PC_G1:
7705 case elfcpp::R_ARM_ALU_PC_G2:
7706 case elfcpp::R_ARM_LDR_PC_G1:
7707 case elfcpp::R_ARM_LDR_PC_G2:
7708 case elfcpp::R_ARM_LDRS_PC_G0:
7709 case elfcpp::R_ARM_LDRS_PC_G1:
7710 case elfcpp::R_ARM_LDRS_PC_G2:
7711 case elfcpp::R_ARM_LDC_PC_G0:
7712 case elfcpp::R_ARM_LDC_PC_G1:
7713 case elfcpp::R_ARM_LDC_PC_G2:
7714 case elfcpp::R_ARM_ALU_SB_G0_NC:
7715 case elfcpp::R_ARM_ALU_SB_G0:
7716 case elfcpp::R_ARM_ALU_SB_G1_NC:
7717 case elfcpp::R_ARM_ALU_SB_G1:
7718 case elfcpp::R_ARM_ALU_SB_G2:
7719 case elfcpp::R_ARM_LDR_SB_G0:
7720 case elfcpp::R_ARM_LDR_SB_G1:
7721 case elfcpp::R_ARM_LDR_SB_G2:
7722 case elfcpp::R_ARM_LDRS_SB_G0:
7723 case elfcpp::R_ARM_LDRS_SB_G1:
7724 case elfcpp::R_ARM_LDRS_SB_G2:
7725 case elfcpp::R_ARM_LDC_SB_G0:
7726 case elfcpp::R_ARM_LDC_SB_G1:
7727 case elfcpp::R_ARM_LDC_SB_G2:
7728 case elfcpp::R_ARM_MOVW_BREL_NC:
7729 case elfcpp::R_ARM_MOVT_BREL:
7730 case elfcpp::R_ARM_MOVW_BREL:
7731 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7732 case elfcpp::R_ARM_THM_MOVT_BREL:
7733 case elfcpp::R_ARM_THM_MOVW_BREL:
7734 case elfcpp::R_ARM_GOTOFF32:
7735 case elfcpp::R_ARM_GOTOFF12:
7736 case elfcpp::R_ARM_SBREL31:
7737 return Symbol::RELATIVE_REF;
7738
7739 case elfcpp::R_ARM_PLT32:
7740 case elfcpp::R_ARM_CALL:
7741 case elfcpp::R_ARM_JUMP24:
7742 case elfcpp::R_ARM_THM_CALL:
7743 case elfcpp::R_ARM_THM_JUMP24:
7744 case elfcpp::R_ARM_THM_JUMP19:
7745 case elfcpp::R_ARM_THM_JUMP6:
7746 case elfcpp::R_ARM_THM_JUMP11:
7747 case elfcpp::R_ARM_THM_JUMP8:
7748 // R_ARM_PREL31 is not used to relocate call/jump instructions but
7749 // in unwind tables. It may point to functions via PLTs.
7750 // So we treat it like call/jump relocations above.
7751 case elfcpp::R_ARM_PREL31:
7752 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
7753
7754 case elfcpp::R_ARM_GOT_BREL:
7755 case elfcpp::R_ARM_GOT_ABS:
7756 case elfcpp::R_ARM_GOT_PREL:
7757 // Absolute in GOT.
7758 return Symbol::ABSOLUTE_REF;
7759
7760 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7761 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7762 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7763 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7764 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7765 return Symbol::TLS_REF;
7766
7767 case elfcpp::R_ARM_TARGET1:
7768 case elfcpp::R_ARM_TARGET2:
7769 case elfcpp::R_ARM_COPY:
7770 case elfcpp::R_ARM_GLOB_DAT:
7771 case elfcpp::R_ARM_JUMP_SLOT:
7772 case elfcpp::R_ARM_RELATIVE:
7773 case elfcpp::R_ARM_PC24:
7774 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7775 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7776 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7777 default:
7778 // Not expected. We will give an error later.
7779 return 0;
7780 }
7781 }
7782
7783 // Report an unsupported relocation against a local symbol.
7784
7785 template<bool big_endian>
7786 void
7787 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7788 Sized_relobj_file<32, big_endian>* object,
7789 unsigned int r_type)
7790 {
7791 gold_error(_("%s: unsupported reloc %u against local symbol"),
7792 object->name().c_str(), r_type);
7793 }
7794
7795 // We are about to emit a dynamic relocation of type R_TYPE. If the
7796 // dynamic linker does not support it, issue an error. The GNU linker
7797 // only issues a non-PIC error for an allocated read-only section.
7798 // Here we know the section is allocated, but we don't know that it is
7799 // read-only. But we check for all the relocation types which the
7800 // glibc dynamic linker supports, so it seems appropriate to issue an
7801 // error even if the section is not read-only.
7802
7803 template<bool big_endian>
7804 void
7805 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7806 unsigned int r_type)
7807 {
7808 switch (r_type)
7809 {
7810 // These are the relocation types supported by glibc for ARM.
7811 case elfcpp::R_ARM_RELATIVE:
7812 case elfcpp::R_ARM_COPY:
7813 case elfcpp::R_ARM_GLOB_DAT:
7814 case elfcpp::R_ARM_JUMP_SLOT:
7815 case elfcpp::R_ARM_ABS32:
7816 case elfcpp::R_ARM_ABS32_NOI:
7817 case elfcpp::R_ARM_PC24:
7818 // FIXME: The following 3 types are not supported by Android's dynamic
7819 // linker.
7820 case elfcpp::R_ARM_TLS_DTPMOD32:
7821 case elfcpp::R_ARM_TLS_DTPOFF32:
7822 case elfcpp::R_ARM_TLS_TPOFF32:
7823 return;
7824
7825 default:
7826 {
7827 // This prevents us from issuing more than one error per reloc
7828 // section. But we can still wind up issuing more than one
7829 // error per object file.
7830 if (this->issued_non_pic_error_)
7831 return;
7832 const Arm_reloc_property* reloc_property =
7833 arm_reloc_property_table->get_reloc_property(r_type);
7834 gold_assert(reloc_property != NULL);
7835 object->error(_("requires unsupported dynamic reloc %s; "
7836 "recompile with -fPIC"),
7837 reloc_property->name().c_str());
7838 this->issued_non_pic_error_ = true;
7839 return;
7840 }
7841
7842 case elfcpp::R_ARM_NONE:
7843 gold_unreachable();
7844 }
7845 }
7846
7847 // Scan a relocation for a local symbol.
7848 // FIXME: This only handles a subset of relocation types used by Android
7849 // on ARM v5te devices.
7850
7851 template<bool big_endian>
7852 inline void
7853 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7854 Layout* layout,
7855 Target_arm* target,
7856 Sized_relobj_file<32, big_endian>* object,
7857 unsigned int data_shndx,
7858 Output_section* output_section,
7859 const elfcpp::Rel<32, big_endian>& reloc,
7860 unsigned int r_type,
7861 const elfcpp::Sym<32, big_endian>& lsym,
7862 bool is_discarded)
7863 {
7864 if (is_discarded)
7865 return;
7866
7867 r_type = get_real_reloc_type(r_type);
7868 switch (r_type)
7869 {
7870 case elfcpp::R_ARM_NONE:
7871 case elfcpp::R_ARM_V4BX:
7872 case elfcpp::R_ARM_GNU_VTENTRY:
7873 case elfcpp::R_ARM_GNU_VTINHERIT:
7874 break;
7875
7876 case elfcpp::R_ARM_ABS32:
7877 case elfcpp::R_ARM_ABS32_NOI:
7878 // If building a shared library (or a position-independent
7879 // executable), we need to create a dynamic relocation for
7880 // this location. The relocation applied at link time will
7881 // apply the link-time value, so we flag the location with
7882 // an R_ARM_RELATIVE relocation so the dynamic loader can
7883 // relocate it easily.
7884 if (parameters->options().output_is_position_independent())
7885 {
7886 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7887 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7888 // If we are to add more other reloc types than R_ARM_ABS32,
7889 // we need to add check_non_pic(object, r_type) here.
7890 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7891 output_section, data_shndx,
7892 reloc.get_r_offset());
7893 }
7894 break;
7895
7896 case elfcpp::R_ARM_ABS16:
7897 case elfcpp::R_ARM_ABS12:
7898 case elfcpp::R_ARM_THM_ABS5:
7899 case elfcpp::R_ARM_ABS8:
7900 case elfcpp::R_ARM_BASE_ABS:
7901 case elfcpp::R_ARM_MOVW_ABS_NC:
7902 case elfcpp::R_ARM_MOVT_ABS:
7903 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7904 case elfcpp::R_ARM_THM_MOVT_ABS:
7905 // If building a shared library (or a position-independent
7906 // executable), we need to create a dynamic relocation for
7907 // this location. Because the addend needs to remain in the
7908 // data section, we need to be careful not to apply this
7909 // relocation statically.
7910 if (parameters->options().output_is_position_independent())
7911 {
7912 check_non_pic(object, r_type);
7913 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7914 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7915 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7916 rel_dyn->add_local(object, r_sym, r_type, output_section,
7917 data_shndx, reloc.get_r_offset());
7918 else
7919 {
7920 gold_assert(lsym.get_st_value() == 0);
7921 unsigned int shndx = lsym.get_st_shndx();
7922 bool is_ordinary;
7923 shndx = object->adjust_sym_shndx(r_sym, shndx,
7924 &is_ordinary);
7925 if (!is_ordinary)
7926 object->error(_("section symbol %u has bad shndx %u"),
7927 r_sym, shndx);
7928 else
7929 rel_dyn->add_local_section(object, shndx,
7930 r_type, output_section,
7931 data_shndx, reloc.get_r_offset());
7932 }
7933 }
7934 break;
7935
7936 case elfcpp::R_ARM_REL32:
7937 case elfcpp::R_ARM_LDR_PC_G0:
7938 case elfcpp::R_ARM_SBREL32:
7939 case elfcpp::R_ARM_THM_CALL:
7940 case elfcpp::R_ARM_THM_PC8:
7941 case elfcpp::R_ARM_BASE_PREL:
7942 case elfcpp::R_ARM_PLT32:
7943 case elfcpp::R_ARM_CALL:
7944 case elfcpp::R_ARM_JUMP24:
7945 case elfcpp::R_ARM_THM_JUMP24:
7946 case elfcpp::R_ARM_SBREL31:
7947 case elfcpp::R_ARM_PREL31:
7948 case elfcpp::R_ARM_MOVW_PREL_NC:
7949 case elfcpp::R_ARM_MOVT_PREL:
7950 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7951 case elfcpp::R_ARM_THM_MOVT_PREL:
7952 case elfcpp::R_ARM_THM_JUMP19:
7953 case elfcpp::R_ARM_THM_JUMP6:
7954 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7955 case elfcpp::R_ARM_THM_PC12:
7956 case elfcpp::R_ARM_REL32_NOI:
7957 case elfcpp::R_ARM_ALU_PC_G0_NC:
7958 case elfcpp::R_ARM_ALU_PC_G0:
7959 case elfcpp::R_ARM_ALU_PC_G1_NC:
7960 case elfcpp::R_ARM_ALU_PC_G1:
7961 case elfcpp::R_ARM_ALU_PC_G2:
7962 case elfcpp::R_ARM_LDR_PC_G1:
7963 case elfcpp::R_ARM_LDR_PC_G2:
7964 case elfcpp::R_ARM_LDRS_PC_G0:
7965 case elfcpp::R_ARM_LDRS_PC_G1:
7966 case elfcpp::R_ARM_LDRS_PC_G2:
7967 case elfcpp::R_ARM_LDC_PC_G0:
7968 case elfcpp::R_ARM_LDC_PC_G1:
7969 case elfcpp::R_ARM_LDC_PC_G2:
7970 case elfcpp::R_ARM_ALU_SB_G0_NC:
7971 case elfcpp::R_ARM_ALU_SB_G0:
7972 case elfcpp::R_ARM_ALU_SB_G1_NC:
7973 case elfcpp::R_ARM_ALU_SB_G1:
7974 case elfcpp::R_ARM_ALU_SB_G2:
7975 case elfcpp::R_ARM_LDR_SB_G0:
7976 case elfcpp::R_ARM_LDR_SB_G1:
7977 case elfcpp::R_ARM_LDR_SB_G2:
7978 case elfcpp::R_ARM_LDRS_SB_G0:
7979 case elfcpp::R_ARM_LDRS_SB_G1:
7980 case elfcpp::R_ARM_LDRS_SB_G2:
7981 case elfcpp::R_ARM_LDC_SB_G0:
7982 case elfcpp::R_ARM_LDC_SB_G1:
7983 case elfcpp::R_ARM_LDC_SB_G2:
7984 case elfcpp::R_ARM_MOVW_BREL_NC:
7985 case elfcpp::R_ARM_MOVT_BREL:
7986 case elfcpp::R_ARM_MOVW_BREL:
7987 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7988 case elfcpp::R_ARM_THM_MOVT_BREL:
7989 case elfcpp::R_ARM_THM_MOVW_BREL:
7990 case elfcpp::R_ARM_THM_JUMP11:
7991 case elfcpp::R_ARM_THM_JUMP8:
7992 // We don't need to do anything for a relative addressing relocation
7993 // against a local symbol if it does not reference the GOT.
7994 break;
7995
7996 case elfcpp::R_ARM_GOTOFF32:
7997 case elfcpp::R_ARM_GOTOFF12:
7998 // We need a GOT section:
7999 target->got_section(symtab, layout);
8000 break;
8001
8002 case elfcpp::R_ARM_GOT_BREL:
8003 case elfcpp::R_ARM_GOT_PREL:
8004 {
8005 // The symbol requires a GOT entry.
8006 Arm_output_data_got<big_endian>* got =
8007 target->got_section(symtab, layout);
8008 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
8009 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
8010 {
8011 // If we are generating a shared object, we need to add a
8012 // dynamic RELATIVE relocation for this symbol's GOT entry.
8013 if (parameters->options().output_is_position_independent())
8014 {
8015 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8016 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
8017 rel_dyn->add_local_relative(
8018 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
8019 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
8020 }
8021 }
8022 }
8023 break;
8024
8025 case elfcpp::R_ARM_TARGET1:
8026 case elfcpp::R_ARM_TARGET2:
8027 // This should have been mapped to another type already.
8028 // Fall through.
8029 case elfcpp::R_ARM_COPY:
8030 case elfcpp::R_ARM_GLOB_DAT:
8031 case elfcpp::R_ARM_JUMP_SLOT:
8032 case elfcpp::R_ARM_RELATIVE:
8033 // These are relocations which should only be seen by the
8034 // dynamic linker, and should never be seen here.
8035 gold_error(_("%s: unexpected reloc %u in object file"),
8036 object->name().c_str(), r_type);
8037 break;
8038
8039
8040 // These are initial TLS relocs, which are expected when
8041 // linking.
8042 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8043 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8044 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8045 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8046 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8047 {
8048 bool output_is_shared = parameters->options().shared();
8049 const tls::Tls_optimization optimized_type
8050 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
8051 r_type);
8052 switch (r_type)
8053 {
8054 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8055 if (optimized_type == tls::TLSOPT_NONE)
8056 {
8057 // Create a pair of GOT entries for the module index and
8058 // dtv-relative offset.
8059 Arm_output_data_got<big_endian>* got
8060 = target->got_section(symtab, layout);
8061 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
8062 unsigned int shndx = lsym.get_st_shndx();
8063 bool is_ordinary;
8064 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
8065 if (!is_ordinary)
8066 {
8067 object->error(_("local symbol %u has bad shndx %u"),
8068 r_sym, shndx);
8069 break;
8070 }
8071
8072 if (!parameters->doing_static_link())
8073 got->add_local_pair_with_rel(object, r_sym, shndx,
8074 GOT_TYPE_TLS_PAIR,
8075 target->rel_dyn_section(layout),
8076 elfcpp::R_ARM_TLS_DTPMOD32);
8077 else
8078 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
8079 object, r_sym);
8080 }
8081 else
8082 // FIXME: TLS optimization not supported yet.
8083 gold_unreachable();
8084 break;
8085
8086 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8087 if (optimized_type == tls::TLSOPT_NONE)
8088 {
8089 // Create a GOT entry for the module index.
8090 target->got_mod_index_entry(symtab, layout, object);
8091 }
8092 else
8093 // FIXME: TLS optimization not supported yet.
8094 gold_unreachable();
8095 break;
8096
8097 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8098 break;
8099
8100 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8101 layout->set_has_static_tls();
8102 if (optimized_type == tls::TLSOPT_NONE)
8103 {
8104 // Create a GOT entry for the tp-relative offset.
8105 Arm_output_data_got<big_endian>* got
8106 = target->got_section(symtab, layout);
8107 unsigned int r_sym =
8108 elfcpp::elf_r_sym<32>(reloc.get_r_info());
8109 if (!parameters->doing_static_link())
8110 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
8111 target->rel_dyn_section(layout),
8112 elfcpp::R_ARM_TLS_TPOFF32);
8113 else if (!object->local_has_got_offset(r_sym,
8114 GOT_TYPE_TLS_OFFSET))
8115 {
8116 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
8117 unsigned int got_offset =
8118 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
8119 got->add_static_reloc(got_offset,
8120 elfcpp::R_ARM_TLS_TPOFF32, object,
8121 r_sym);
8122 }
8123 }
8124 else
8125 // FIXME: TLS optimization not supported yet.
8126 gold_unreachable();
8127 break;
8128
8129 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8130 layout->set_has_static_tls();
8131 if (output_is_shared)
8132 {
8133 // We need to create a dynamic relocation.
8134 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
8135 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
8136 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8137 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
8138 output_section, data_shndx,
8139 reloc.get_r_offset());
8140 }
8141 break;
8142
8143 default:
8144 gold_unreachable();
8145 }
8146 }
8147 break;
8148
8149 case elfcpp::R_ARM_PC24:
8150 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
8151 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
8152 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
8153 default:
8154 unsupported_reloc_local(object, r_type);
8155 break;
8156 }
8157 }
8158
8159 // Report an unsupported relocation against a global symbol.
8160
8161 template<bool big_endian>
8162 void
8163 Target_arm<big_endian>::Scan::unsupported_reloc_global(
8164 Sized_relobj_file<32, big_endian>* object,
8165 unsigned int r_type,
8166 Symbol* gsym)
8167 {
8168 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
8169 object->name().c_str(), r_type, gsym->demangled_name().c_str());
8170 }
8171
8172 template<bool big_endian>
8173 inline bool
8174 Target_arm<big_endian>::Scan::possible_function_pointer_reloc(
8175 unsigned int r_type)
8176 {
8177 switch (r_type)
8178 {
8179 case elfcpp::R_ARM_PC24:
8180 case elfcpp::R_ARM_THM_CALL:
8181 case elfcpp::R_ARM_PLT32:
8182 case elfcpp::R_ARM_CALL:
8183 case elfcpp::R_ARM_JUMP24:
8184 case elfcpp::R_ARM_THM_JUMP24:
8185 case elfcpp::R_ARM_SBREL31:
8186 case elfcpp::R_ARM_PREL31:
8187 case elfcpp::R_ARM_THM_JUMP19:
8188 case elfcpp::R_ARM_THM_JUMP6:
8189 case elfcpp::R_ARM_THM_JUMP11:
8190 case elfcpp::R_ARM_THM_JUMP8:
8191 // All the relocations above are branches except SBREL31 and PREL31.
8192 return false;
8193
8194 default:
8195 // Be conservative and assume this is a function pointer.
8196 return true;
8197 }
8198 }
8199
8200 template<bool big_endian>
8201 inline bool
8202 Target_arm<big_endian>::Scan::local_reloc_may_be_function_pointer(
8203 Symbol_table*,
8204 Layout*,
8205 Target_arm<big_endian>* target,
8206 Sized_relobj_file<32, big_endian>*,
8207 unsigned int,
8208 Output_section*,
8209 const elfcpp::Rel<32, big_endian>&,
8210 unsigned int r_type,
8211 const elfcpp::Sym<32, big_endian>&)
8212 {
8213 r_type = target->get_real_reloc_type(r_type);
8214 return possible_function_pointer_reloc(r_type);
8215 }
8216
8217 template<bool big_endian>
8218 inline bool
8219 Target_arm<big_endian>::Scan::global_reloc_may_be_function_pointer(
8220 Symbol_table*,
8221 Layout*,
8222 Target_arm<big_endian>* target,
8223 Sized_relobj_file<32, big_endian>*,
8224 unsigned int,
8225 Output_section*,
8226 const elfcpp::Rel<32, big_endian>&,
8227 unsigned int r_type,
8228 Symbol* gsym)
8229 {
8230 // GOT is not a function.
8231 if (strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
8232 return false;
8233
8234 r_type = target->get_real_reloc_type(r_type);
8235 return possible_function_pointer_reloc(r_type);
8236 }
8237
8238 // Scan a relocation for a global symbol.
8239
8240 template<bool big_endian>
8241 inline void
8242 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
8243 Layout* layout,
8244 Target_arm* target,
8245 Sized_relobj_file<32, big_endian>* object,
8246 unsigned int data_shndx,
8247 Output_section* output_section,
8248 const elfcpp::Rel<32, big_endian>& reloc,
8249 unsigned int r_type,
8250 Symbol* gsym)
8251 {
8252 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
8253 // section. We check here to avoid creating a dynamic reloc against
8254 // _GLOBAL_OFFSET_TABLE_.
8255 if (!target->has_got_section()
8256 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
8257 target->got_section(symtab, layout);
8258
8259 r_type = get_real_reloc_type(r_type);
8260 switch (r_type)
8261 {
8262 case elfcpp::R_ARM_NONE:
8263 case elfcpp::R_ARM_V4BX:
8264 case elfcpp::R_ARM_GNU_VTENTRY:
8265 case elfcpp::R_ARM_GNU_VTINHERIT:
8266 break;
8267
8268 case elfcpp::R_ARM_ABS32:
8269 case elfcpp::R_ARM_ABS16:
8270 case elfcpp::R_ARM_ABS12:
8271 case elfcpp::R_ARM_THM_ABS5:
8272 case elfcpp::R_ARM_ABS8:
8273 case elfcpp::R_ARM_BASE_ABS:
8274 case elfcpp::R_ARM_MOVW_ABS_NC:
8275 case elfcpp::R_ARM_MOVT_ABS:
8276 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8277 case elfcpp::R_ARM_THM_MOVT_ABS:
8278 case elfcpp::R_ARM_ABS32_NOI:
8279 // Absolute addressing relocations.
8280 {
8281 // Make a PLT entry if necessary.
8282 if (this->symbol_needs_plt_entry(gsym))
8283 {
8284 target->make_plt_entry(symtab, layout, gsym);
8285 // Since this is not a PC-relative relocation, we may be
8286 // taking the address of a function. In that case we need to
8287 // set the entry in the dynamic symbol table to the address of
8288 // the PLT entry.
8289 if (gsym->is_from_dynobj() && !parameters->options().shared())
8290 gsym->set_needs_dynsym_value();
8291 }
8292 // Make a dynamic relocation if necessary.
8293 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
8294 {
8295 if (gsym->may_need_copy_reloc())
8296 {
8297 target->copy_reloc(symtab, layout, object,
8298 data_shndx, output_section, gsym, reloc);
8299 }
8300 else if ((r_type == elfcpp::R_ARM_ABS32
8301 || r_type == elfcpp::R_ARM_ABS32_NOI)
8302 && gsym->can_use_relative_reloc(false))
8303 {
8304 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8305 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
8306 output_section, object,
8307 data_shndx, reloc.get_r_offset());
8308 }
8309 else
8310 {
8311 check_non_pic(object, r_type);
8312 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8313 rel_dyn->add_global(gsym, r_type, output_section, object,
8314 data_shndx, reloc.get_r_offset());
8315 }
8316 }
8317 }
8318 break;
8319
8320 case elfcpp::R_ARM_GOTOFF32:
8321 case elfcpp::R_ARM_GOTOFF12:
8322 // We need a GOT section.
8323 target->got_section(symtab, layout);
8324 break;
8325
8326 case elfcpp::R_ARM_REL32:
8327 case elfcpp::R_ARM_LDR_PC_G0:
8328 case elfcpp::R_ARM_SBREL32:
8329 case elfcpp::R_ARM_THM_PC8:
8330 case elfcpp::R_ARM_BASE_PREL:
8331 case elfcpp::R_ARM_MOVW_PREL_NC:
8332 case elfcpp::R_ARM_MOVT_PREL:
8333 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8334 case elfcpp::R_ARM_THM_MOVT_PREL:
8335 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8336 case elfcpp::R_ARM_THM_PC12:
8337 case elfcpp::R_ARM_REL32_NOI:
8338 case elfcpp::R_ARM_ALU_PC_G0_NC:
8339 case elfcpp::R_ARM_ALU_PC_G0:
8340 case elfcpp::R_ARM_ALU_PC_G1_NC:
8341 case elfcpp::R_ARM_ALU_PC_G1:
8342 case elfcpp::R_ARM_ALU_PC_G2:
8343 case elfcpp::R_ARM_LDR_PC_G1:
8344 case elfcpp::R_ARM_LDR_PC_G2:
8345 case elfcpp::R_ARM_LDRS_PC_G0:
8346 case elfcpp::R_ARM_LDRS_PC_G1:
8347 case elfcpp::R_ARM_LDRS_PC_G2:
8348 case elfcpp::R_ARM_LDC_PC_G0:
8349 case elfcpp::R_ARM_LDC_PC_G1:
8350 case elfcpp::R_ARM_LDC_PC_G2:
8351 case elfcpp::R_ARM_ALU_SB_G0_NC:
8352 case elfcpp::R_ARM_ALU_SB_G0:
8353 case elfcpp::R_ARM_ALU_SB_G1_NC:
8354 case elfcpp::R_ARM_ALU_SB_G1:
8355 case elfcpp::R_ARM_ALU_SB_G2:
8356 case elfcpp::R_ARM_LDR_SB_G0:
8357 case elfcpp::R_ARM_LDR_SB_G1:
8358 case elfcpp::R_ARM_LDR_SB_G2:
8359 case elfcpp::R_ARM_LDRS_SB_G0:
8360 case elfcpp::R_ARM_LDRS_SB_G1:
8361 case elfcpp::R_ARM_LDRS_SB_G2:
8362 case elfcpp::R_ARM_LDC_SB_G0:
8363 case elfcpp::R_ARM_LDC_SB_G1:
8364 case elfcpp::R_ARM_LDC_SB_G2:
8365 case elfcpp::R_ARM_MOVW_BREL_NC:
8366 case elfcpp::R_ARM_MOVT_BREL:
8367 case elfcpp::R_ARM_MOVW_BREL:
8368 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8369 case elfcpp::R_ARM_THM_MOVT_BREL:
8370 case elfcpp::R_ARM_THM_MOVW_BREL:
8371 // Relative addressing relocations.
8372 {
8373 // Make a dynamic relocation if necessary.
8374 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
8375 {
8376 if (target->may_need_copy_reloc(gsym))
8377 {
8378 target->copy_reloc(symtab, layout, object,
8379 data_shndx, output_section, gsym, reloc);
8380 }
8381 else
8382 {
8383 check_non_pic(object, r_type);
8384 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8385 rel_dyn->add_global(gsym, r_type, output_section, object,
8386 data_shndx, reloc.get_r_offset());
8387 }
8388 }
8389 }
8390 break;
8391
8392 case elfcpp::R_ARM_THM_CALL:
8393 case elfcpp::R_ARM_PLT32:
8394 case elfcpp::R_ARM_CALL:
8395 case elfcpp::R_ARM_JUMP24:
8396 case elfcpp::R_ARM_THM_JUMP24:
8397 case elfcpp::R_ARM_SBREL31:
8398 case elfcpp::R_ARM_PREL31:
8399 case elfcpp::R_ARM_THM_JUMP19:
8400 case elfcpp::R_ARM_THM_JUMP6:
8401 case elfcpp::R_ARM_THM_JUMP11:
8402 case elfcpp::R_ARM_THM_JUMP8:
8403 // All the relocation above are branches except for the PREL31 ones.
8404 // A PREL31 relocation can point to a personality function in a shared
8405 // library. In that case we want to use a PLT because we want to
8406 // call the personality routine and the dynamic linkers we care about
8407 // do not support dynamic PREL31 relocations. An REL31 relocation may
8408 // point to a function whose unwinding behaviour is being described but
8409 // we will not mistakenly generate a PLT for that because we should use
8410 // a local section symbol.
8411
8412 // If the symbol is fully resolved, this is just a relative
8413 // local reloc. Otherwise we need a PLT entry.
8414 if (gsym->final_value_is_known())
8415 break;
8416 // If building a shared library, we can also skip the PLT entry
8417 // if the symbol is defined in the output file and is protected
8418 // or hidden.
8419 if (gsym->is_defined()
8420 && !gsym->is_from_dynobj()
8421 && !gsym->is_preemptible())
8422 break;
8423 target->make_plt_entry(symtab, layout, gsym);
8424 break;
8425
8426 case elfcpp::R_ARM_GOT_BREL:
8427 case elfcpp::R_ARM_GOT_ABS:
8428 case elfcpp::R_ARM_GOT_PREL:
8429 {
8430 // The symbol requires a GOT entry.
8431 Arm_output_data_got<big_endian>* got =
8432 target->got_section(symtab, layout);
8433 if (gsym->final_value_is_known())
8434 got->add_global(gsym, GOT_TYPE_STANDARD);
8435 else
8436 {
8437 // If this symbol is not fully resolved, we need to add a
8438 // GOT entry with a dynamic relocation.
8439 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8440 if (gsym->is_from_dynobj()
8441 || gsym->is_undefined()
8442 || gsym->is_preemptible()
8443 || (gsym->visibility() == elfcpp::STV_PROTECTED
8444 && parameters->options().shared()))
8445 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
8446 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
8447 else
8448 {
8449 if (got->add_global(gsym, GOT_TYPE_STANDARD))
8450 rel_dyn->add_global_relative(
8451 gsym, elfcpp::R_ARM_RELATIVE, got,
8452 gsym->got_offset(GOT_TYPE_STANDARD));
8453 }
8454 }
8455 }
8456 break;
8457
8458 case elfcpp::R_ARM_TARGET1:
8459 case elfcpp::R_ARM_TARGET2:
8460 // These should have been mapped to other types already.
8461 // Fall through.
8462 case elfcpp::R_ARM_COPY:
8463 case elfcpp::R_ARM_GLOB_DAT:
8464 case elfcpp::R_ARM_JUMP_SLOT:
8465 case elfcpp::R_ARM_RELATIVE:
8466 // These are relocations which should only be seen by the
8467 // dynamic linker, and should never be seen here.
8468 gold_error(_("%s: unexpected reloc %u in object file"),
8469 object->name().c_str(), r_type);
8470 break;
8471
8472 // These are initial tls relocs, which are expected when
8473 // linking.
8474 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8475 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8476 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8477 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8478 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8479 {
8480 const bool is_final = gsym->final_value_is_known();
8481 const tls::Tls_optimization optimized_type
8482 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8483 switch (r_type)
8484 {
8485 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8486 if (optimized_type == tls::TLSOPT_NONE)
8487 {
8488 // Create a pair of GOT entries for the module index and
8489 // dtv-relative offset.
8490 Arm_output_data_got<big_endian>* got
8491 = target->got_section(symtab, layout);
8492 if (!parameters->doing_static_link())
8493 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
8494 target->rel_dyn_section(layout),
8495 elfcpp::R_ARM_TLS_DTPMOD32,
8496 elfcpp::R_ARM_TLS_DTPOFF32);
8497 else
8498 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
8499 }
8500 else
8501 // FIXME: TLS optimization not supported yet.
8502 gold_unreachable();
8503 break;
8504
8505 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8506 if (optimized_type == tls::TLSOPT_NONE)
8507 {
8508 // Create a GOT entry for the module index.
8509 target->got_mod_index_entry(symtab, layout, object);
8510 }
8511 else
8512 // FIXME: TLS optimization not supported yet.
8513 gold_unreachable();
8514 break;
8515
8516 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8517 break;
8518
8519 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8520 layout->set_has_static_tls();
8521 if (optimized_type == tls::TLSOPT_NONE)
8522 {
8523 // Create a GOT entry for the tp-relative offset.
8524 Arm_output_data_got<big_endian>* got
8525 = target->got_section(symtab, layout);
8526 if (!parameters->doing_static_link())
8527 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
8528 target->rel_dyn_section(layout),
8529 elfcpp::R_ARM_TLS_TPOFF32);
8530 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
8531 {
8532 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
8533 unsigned int got_offset =
8534 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
8535 got->add_static_reloc(got_offset,
8536 elfcpp::R_ARM_TLS_TPOFF32, gsym);
8537 }
8538 }
8539 else
8540 // FIXME: TLS optimization not supported yet.
8541 gold_unreachable();
8542 break;
8543
8544 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8545 layout->set_has_static_tls();
8546 if (parameters->options().shared())
8547 {
8548 // We need to create a dynamic relocation.
8549 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8550 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
8551 output_section, object,
8552 data_shndx, reloc.get_r_offset());
8553 }
8554 break;
8555
8556 default:
8557 gold_unreachable();
8558 }
8559 }
8560 break;
8561
8562 case elfcpp::R_ARM_PC24:
8563 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
8564 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
8565 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
8566 default:
8567 unsupported_reloc_global(object, r_type, gsym);
8568 break;
8569 }
8570 }
8571
8572 // Process relocations for gc.
8573
8574 template<bool big_endian>
8575 void
8576 Target_arm<big_endian>::gc_process_relocs(
8577 Symbol_table* symtab,
8578 Layout* layout,
8579 Sized_relobj_file<32, big_endian>* object,
8580 unsigned int data_shndx,
8581 unsigned int,
8582 const unsigned char* prelocs,
8583 size_t reloc_count,
8584 Output_section* output_section,
8585 bool needs_special_offset_handling,
8586 size_t local_symbol_count,
8587 const unsigned char* plocal_symbols)
8588 {
8589 typedef Target_arm<big_endian> Arm;
8590 typedef typename Target_arm<big_endian>::Scan Scan;
8591
8592 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan,
8593 typename Target_arm::Relocatable_size_for_reloc>(
8594 symtab,
8595 layout,
8596 this,
8597 object,
8598 data_shndx,
8599 prelocs,
8600 reloc_count,
8601 output_section,
8602 needs_special_offset_handling,
8603 local_symbol_count,
8604 plocal_symbols);
8605 }
8606
8607 // Scan relocations for a section.
8608
8609 template<bool big_endian>
8610 void
8611 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
8612 Layout* layout,
8613 Sized_relobj_file<32, big_endian>* object,
8614 unsigned int data_shndx,
8615 unsigned int sh_type,
8616 const unsigned char* prelocs,
8617 size_t reloc_count,
8618 Output_section* output_section,
8619 bool needs_special_offset_handling,
8620 size_t local_symbol_count,
8621 const unsigned char* plocal_symbols)
8622 {
8623 typedef typename Target_arm<big_endian>::Scan Scan;
8624 if (sh_type == elfcpp::SHT_RELA)
8625 {
8626 gold_error(_("%s: unsupported RELA reloc section"),
8627 object->name().c_str());
8628 return;
8629 }
8630
8631 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
8632 symtab,
8633 layout,
8634 this,
8635 object,
8636 data_shndx,
8637 prelocs,
8638 reloc_count,
8639 output_section,
8640 needs_special_offset_handling,
8641 local_symbol_count,
8642 plocal_symbols);
8643 }
8644
8645 // Finalize the sections.
8646
8647 template<bool big_endian>
8648 void
8649 Target_arm<big_endian>::do_finalize_sections(
8650 Layout* layout,
8651 const Input_objects* input_objects,
8652 Symbol_table*)
8653 {
8654 bool merged_any_attributes = false;
8655 // Merge processor-specific flags.
8656 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
8657 p != input_objects->relobj_end();
8658 ++p)
8659 {
8660 Arm_relobj<big_endian>* arm_relobj =
8661 Arm_relobj<big_endian>::as_arm_relobj(*p);
8662 if (arm_relobj->merge_flags_and_attributes())
8663 {
8664 this->merge_processor_specific_flags(
8665 arm_relobj->name(),
8666 arm_relobj->processor_specific_flags());
8667 this->merge_object_attributes(arm_relobj->name().c_str(),
8668 arm_relobj->attributes_section_data());
8669 merged_any_attributes = true;
8670 }
8671 }
8672
8673 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
8674 p != input_objects->dynobj_end();
8675 ++p)
8676 {
8677 Arm_dynobj<big_endian>* arm_dynobj =
8678 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
8679 this->merge_processor_specific_flags(
8680 arm_dynobj->name(),
8681 arm_dynobj->processor_specific_flags());
8682 this->merge_object_attributes(arm_dynobj->name().c_str(),
8683 arm_dynobj->attributes_section_data());
8684 merged_any_attributes = true;
8685 }
8686
8687 // Create an empty uninitialized attribute section if we still don't have it
8688 // at this moment. This happens if there is no attributes sections in all
8689 // inputs.
8690 if (this->attributes_section_data_ == NULL)
8691 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
8692
8693 const Object_attribute* cpu_arch_attr =
8694 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
8695 // Check if we need to use Cortex-A8 workaround.
8696 if (parameters->options().user_set_fix_cortex_a8())
8697 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
8698 else
8699 {
8700 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
8701 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
8702 // profile.
8703 const Object_attribute* cpu_arch_profile_attr =
8704 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
8705 this->fix_cortex_a8_ =
8706 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
8707 && (cpu_arch_profile_attr->int_value() == 'A'
8708 || cpu_arch_profile_attr->int_value() == 0));
8709 }
8710
8711 // Check if we can use V4BX interworking.
8712 // The V4BX interworking stub contains BX instruction,
8713 // which is not specified for some profiles.
8714 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
8715 && !this->may_use_v4t_interworking())
8716 gold_error(_("unable to provide V4BX reloc interworking fix up; "
8717 "the target profile does not support BX instruction"));
8718
8719 // Fill in some more dynamic tags.
8720 const Reloc_section* rel_plt = (this->plt_ == NULL
8721 ? NULL
8722 : this->plt_->rel_plt());
8723 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
8724 this->rel_dyn_, true, false);
8725
8726 // Emit any relocs we saved in an attempt to avoid generating COPY
8727 // relocs.
8728 if (this->copy_relocs_.any_saved_relocs())
8729 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8730
8731 // Handle the .ARM.exidx section.
8732 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8733
8734 if (!parameters->options().relocatable())
8735 {
8736 if (exidx_section != NULL
8737 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX)
8738 {
8739 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8740 // the .ARM.exidx section.
8741 if (!layout->script_options()->saw_phdrs_clause())
8742 {
8743 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0,
8744 0)
8745 == NULL);
8746 Output_segment* exidx_segment =
8747 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8748 exidx_segment->add_output_section_to_nonload(exidx_section,
8749 elfcpp::PF_R);
8750 }
8751 }
8752 }
8753
8754 // Create an .ARM.attributes section if we have merged any attributes
8755 // from inputs.
8756 if (merged_any_attributes)
8757 {
8758 Output_attributes_section_data* attributes_section =
8759 new Output_attributes_section_data(*this->attributes_section_data_);
8760 layout->add_output_section_data(".ARM.attributes",
8761 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8762 attributes_section, ORDER_INVALID,
8763 false);
8764 }
8765
8766 // Fix up links in section EXIDX headers.
8767 for (Layout::Section_list::const_iterator p = layout->section_list().begin();
8768 p != layout->section_list().end();
8769 ++p)
8770 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
8771 {
8772 Arm_output_section<big_endian>* os =
8773 Arm_output_section<big_endian>::as_arm_output_section(*p);
8774 os->set_exidx_section_link();
8775 }
8776 }
8777
8778 // Return whether a direct absolute static relocation needs to be applied.
8779 // In cases where Scan::local() or Scan::global() has created
8780 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8781 // of the relocation is carried in the data, and we must not
8782 // apply the static relocation.
8783
8784 template<bool big_endian>
8785 inline bool
8786 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8787 const Sized_symbol<32>* gsym,
8788 unsigned int r_type,
8789 bool is_32bit,
8790 Output_section* output_section)
8791 {
8792 // If the output section is not allocated, then we didn't call
8793 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8794 // the reloc here.
8795 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8796 return true;
8797
8798 int ref_flags = Scan::get_reference_flags(r_type);
8799
8800 // For local symbols, we will have created a non-RELATIVE dynamic
8801 // relocation only if (a) the output is position independent,
8802 // (b) the relocation is absolute (not pc- or segment-relative), and
8803 // (c) the relocation is not 32 bits wide.
8804 if (gsym == NULL)
8805 return !(parameters->options().output_is_position_independent()
8806 && (ref_flags & Symbol::ABSOLUTE_REF)
8807 && !is_32bit);
8808
8809 // For global symbols, we use the same helper routines used in the
8810 // scan pass. If we did not create a dynamic relocation, or if we
8811 // created a RELATIVE dynamic relocation, we should apply the static
8812 // relocation.
8813 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8814 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8815 && gsym->can_use_relative_reloc(ref_flags
8816 & Symbol::FUNCTION_CALL);
8817 return !has_dyn || is_rel;
8818 }
8819
8820 // Perform a relocation.
8821
8822 template<bool big_endian>
8823 inline bool
8824 Target_arm<big_endian>::Relocate::relocate(
8825 const Relocate_info<32, big_endian>* relinfo,
8826 Target_arm* target,
8827 Output_section* output_section,
8828 size_t relnum,
8829 const elfcpp::Rel<32, big_endian>& rel,
8830 unsigned int r_type,
8831 const Sized_symbol<32>* gsym,
8832 const Symbol_value<32>* psymval,
8833 unsigned char* view,
8834 Arm_address address,
8835 section_size_type view_size)
8836 {
8837 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8838
8839 r_type = get_real_reloc_type(r_type);
8840 const Arm_reloc_property* reloc_property =
8841 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8842 if (reloc_property == NULL)
8843 {
8844 std::string reloc_name =
8845 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8846 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8847 _("cannot relocate %s in object file"),
8848 reloc_name.c_str());
8849 return true;
8850 }
8851
8852 const Arm_relobj<big_endian>* object =
8853 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8854
8855 // If the final branch target of a relocation is THUMB instruction, this
8856 // is 1. Otherwise it is 0.
8857 Arm_address thumb_bit = 0;
8858 Symbol_value<32> symval;
8859 bool is_weakly_undefined_without_plt = false;
8860 bool have_got_offset = false;
8861 unsigned int got_offset = 0;
8862
8863 // If the relocation uses the GOT entry of a symbol instead of the symbol
8864 // itself, we don't care about whether the symbol is defined or what kind
8865 // of symbol it is.
8866 if (reloc_property->uses_got_entry())
8867 {
8868 // Get the GOT offset.
8869 // The GOT pointer points to the end of the GOT section.
8870 // We need to subtract the size of the GOT section to get
8871 // the actual offset to use in the relocation.
8872 // TODO: We should move GOT offset computing code in TLS relocations
8873 // to here.
8874 switch (r_type)
8875 {
8876 case elfcpp::R_ARM_GOT_BREL:
8877 case elfcpp::R_ARM_GOT_PREL:
8878 if (gsym != NULL)
8879 {
8880 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8881 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8882 - target->got_size());
8883 }
8884 else
8885 {
8886 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8887 gold_assert(object->local_has_got_offset(r_sym,
8888 GOT_TYPE_STANDARD));
8889 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8890 - target->got_size());
8891 }
8892 have_got_offset = true;
8893 break;
8894
8895 default:
8896 break;
8897 }
8898 }
8899 else if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8900 {
8901 if (gsym != NULL)
8902 {
8903 // This is a global symbol. Determine if we use PLT and if the
8904 // final target is THUMB.
8905 if (gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
8906 {
8907 // This uses a PLT, change the symbol value.
8908 symval.set_output_value(target->plt_section()->address()
8909 + gsym->plt_offset());
8910 psymval = &symval;
8911 }
8912 else if (gsym->is_weak_undefined())
8913 {
8914 // This is a weakly undefined symbol and we do not use PLT
8915 // for this relocation. A branch targeting this symbol will
8916 // be converted into an NOP.
8917 is_weakly_undefined_without_plt = true;
8918 }
8919 else if (gsym->is_undefined() && reloc_property->uses_symbol())
8920 {
8921 // This relocation uses the symbol value but the symbol is
8922 // undefined. Exit early and have the caller reporting an
8923 // error.
8924 return true;
8925 }
8926 else
8927 {
8928 // Set thumb bit if symbol:
8929 // -Has type STT_ARM_TFUNC or
8930 // -Has type STT_FUNC, is defined and with LSB in value set.
8931 thumb_bit =
8932 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8933 || (gsym->type() == elfcpp::STT_FUNC
8934 && !gsym->is_undefined()
8935 && ((psymval->value(object, 0) & 1) != 0)))
8936 ? 1
8937 : 0);
8938 }
8939 }
8940 else
8941 {
8942 // This is a local symbol. Determine if the final target is THUMB.
8943 // We saved this information when all the local symbols were read.
8944 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8945 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8946 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8947 }
8948 }
8949 else
8950 {
8951 // This is a fake relocation synthesized for a stub. It does not have
8952 // a real symbol. We just look at the LSB of the symbol value to
8953 // determine if the target is THUMB or not.
8954 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8955 }
8956
8957 // Strip LSB if this points to a THUMB target.
8958 if (thumb_bit != 0
8959 && reloc_property->uses_thumb_bit()
8960 && ((psymval->value(object, 0) & 1) != 0))
8961 {
8962 Arm_address stripped_value =
8963 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8964 symval.set_output_value(stripped_value);
8965 psymval = &symval;
8966 }
8967
8968 // To look up relocation stubs, we need to pass the symbol table index of
8969 // a local symbol.
8970 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8971
8972 // Get the addressing origin of the output segment defining the
8973 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8974 Arm_address sym_origin = 0;
8975 if (reloc_property->uses_symbol_base())
8976 {
8977 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8978 // R_ARM_BASE_ABS with the NULL symbol will give the
8979 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8980 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8981 sym_origin = target->got_plt_section()->address();
8982 else if (gsym == NULL)
8983 sym_origin = 0;
8984 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8985 sym_origin = gsym->output_segment()->vaddr();
8986 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8987 sym_origin = gsym->output_data()->address();
8988
8989 // TODO: Assumes the segment base to be zero for the global symbols
8990 // till the proper support for the segment-base-relative addressing
8991 // will be implemented. This is consistent with GNU ld.
8992 }
8993
8994 // For relative addressing relocation, find out the relative address base.
8995 Arm_address relative_address_base = 0;
8996 switch(reloc_property->relative_address_base())
8997 {
8998 case Arm_reloc_property::RAB_NONE:
8999 // Relocations with relative address bases RAB_TLS and RAB_tp are
9000 // handled by relocate_tls. So we do not need to do anything here.
9001 case Arm_reloc_property::RAB_TLS:
9002 case Arm_reloc_property::RAB_tp:
9003 break;
9004 case Arm_reloc_property::RAB_B_S:
9005 relative_address_base = sym_origin;
9006 break;
9007 case Arm_reloc_property::RAB_GOT_ORG:
9008 relative_address_base = target->got_plt_section()->address();
9009 break;
9010 case Arm_reloc_property::RAB_P:
9011 relative_address_base = address;
9012 break;
9013 case Arm_reloc_property::RAB_Pa:
9014 relative_address_base = address & 0xfffffffcU;
9015 break;
9016 default:
9017 gold_unreachable();
9018 }
9019
9020 typename Arm_relocate_functions::Status reloc_status =
9021 Arm_relocate_functions::STATUS_OKAY;
9022 bool check_overflow = reloc_property->checks_overflow();
9023 switch (r_type)
9024 {
9025 case elfcpp::R_ARM_NONE:
9026 break;
9027
9028 case elfcpp::R_ARM_ABS8:
9029 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9030 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
9031 break;
9032
9033 case elfcpp::R_ARM_ABS12:
9034 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9035 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
9036 break;
9037
9038 case elfcpp::R_ARM_ABS16:
9039 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9040 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
9041 break;
9042
9043 case elfcpp::R_ARM_ABS32:
9044 if (should_apply_static_reloc(gsym, r_type, true, output_section))
9045 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
9046 thumb_bit);
9047 break;
9048
9049 case elfcpp::R_ARM_ABS32_NOI:
9050 if (should_apply_static_reloc(gsym, r_type, true, output_section))
9051 // No thumb bit for this relocation: (S + A)
9052 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
9053 0);
9054 break;
9055
9056 case elfcpp::R_ARM_MOVW_ABS_NC:
9057 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9058 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
9059 0, thumb_bit,
9060 check_overflow);
9061 break;
9062
9063 case elfcpp::R_ARM_MOVT_ABS:
9064 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9065 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
9066 break;
9067
9068 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
9069 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9070 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
9071 0, thumb_bit, false);
9072 break;
9073
9074 case elfcpp::R_ARM_THM_MOVT_ABS:
9075 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9076 reloc_status = Arm_relocate_functions::thm_movt(view, object,
9077 psymval, 0);
9078 break;
9079
9080 case elfcpp::R_ARM_MOVW_PREL_NC:
9081 case elfcpp::R_ARM_MOVW_BREL_NC:
9082 case elfcpp::R_ARM_MOVW_BREL:
9083 reloc_status =
9084 Arm_relocate_functions::movw(view, object, psymval,
9085 relative_address_base, thumb_bit,
9086 check_overflow);
9087 break;
9088
9089 case elfcpp::R_ARM_MOVT_PREL:
9090 case elfcpp::R_ARM_MOVT_BREL:
9091 reloc_status =
9092 Arm_relocate_functions::movt(view, object, psymval,
9093 relative_address_base);
9094 break;
9095
9096 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
9097 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
9098 case elfcpp::R_ARM_THM_MOVW_BREL:
9099 reloc_status =
9100 Arm_relocate_functions::thm_movw(view, object, psymval,
9101 relative_address_base,
9102 thumb_bit, check_overflow);
9103 break;
9104
9105 case elfcpp::R_ARM_THM_MOVT_PREL:
9106 case elfcpp::R_ARM_THM_MOVT_BREL:
9107 reloc_status =
9108 Arm_relocate_functions::thm_movt(view, object, psymval,
9109 relative_address_base);
9110 break;
9111
9112 case elfcpp::R_ARM_REL32:
9113 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
9114 address, thumb_bit);
9115 break;
9116
9117 case elfcpp::R_ARM_THM_ABS5:
9118 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9119 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
9120 break;
9121
9122 // Thumb long branches.
9123 case elfcpp::R_ARM_THM_CALL:
9124 case elfcpp::R_ARM_THM_XPC22:
9125 case elfcpp::R_ARM_THM_JUMP24:
9126 reloc_status =
9127 Arm_relocate_functions::thumb_branch_common(
9128 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
9129 thumb_bit, is_weakly_undefined_without_plt);
9130 break;
9131
9132 case elfcpp::R_ARM_GOTOFF32:
9133 {
9134 Arm_address got_origin;
9135 got_origin = target->got_plt_section()->address();
9136 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
9137 got_origin, thumb_bit);
9138 }
9139 break;
9140
9141 case elfcpp::R_ARM_BASE_PREL:
9142 gold_assert(gsym != NULL);
9143 reloc_status =
9144 Arm_relocate_functions::base_prel(view, sym_origin, address);
9145 break;
9146
9147 case elfcpp::R_ARM_BASE_ABS:
9148 if (should_apply_static_reloc(gsym, r_type, false, output_section))
9149 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
9150 break;
9151
9152 case elfcpp::R_ARM_GOT_BREL:
9153 gold_assert(have_got_offset);
9154 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
9155 break;
9156
9157 case elfcpp::R_ARM_GOT_PREL:
9158 gold_assert(have_got_offset);
9159 // Get the address origin for GOT PLT, which is allocated right
9160 // after the GOT section, to calculate an absolute address of
9161 // the symbol GOT entry (got_origin + got_offset).
9162 Arm_address got_origin;
9163 got_origin = target->got_plt_section()->address();
9164 reloc_status = Arm_relocate_functions::got_prel(view,
9165 got_origin + got_offset,
9166 address);
9167 break;
9168
9169 case elfcpp::R_ARM_PLT32:
9170 case elfcpp::R_ARM_CALL:
9171 case elfcpp::R_ARM_JUMP24:
9172 case elfcpp::R_ARM_XPC25:
9173 gold_assert(gsym == NULL
9174 || gsym->has_plt_offset()
9175 || gsym->final_value_is_known()
9176 || (gsym->is_defined()
9177 && !gsym->is_from_dynobj()
9178 && !gsym->is_preemptible()));
9179 reloc_status =
9180 Arm_relocate_functions::arm_branch_common(
9181 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
9182 thumb_bit, is_weakly_undefined_without_plt);
9183 break;
9184
9185 case elfcpp::R_ARM_THM_JUMP19:
9186 reloc_status =
9187 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
9188 thumb_bit);
9189 break;
9190
9191 case elfcpp::R_ARM_THM_JUMP6:
9192 reloc_status =
9193 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
9194 break;
9195
9196 case elfcpp::R_ARM_THM_JUMP8:
9197 reloc_status =
9198 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
9199 break;
9200
9201 case elfcpp::R_ARM_THM_JUMP11:
9202 reloc_status =
9203 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
9204 break;
9205
9206 case elfcpp::R_ARM_PREL31:
9207 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
9208 address, thumb_bit);
9209 break;
9210
9211 case elfcpp::R_ARM_V4BX:
9212 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
9213 {
9214 const bool is_v4bx_interworking =
9215 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
9216 reloc_status =
9217 Arm_relocate_functions::v4bx(relinfo, view, object, address,
9218 is_v4bx_interworking);
9219 }
9220 break;
9221
9222 case elfcpp::R_ARM_THM_PC8:
9223 reloc_status =
9224 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
9225 break;
9226
9227 case elfcpp::R_ARM_THM_PC12:
9228 reloc_status =
9229 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
9230 break;
9231
9232 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
9233 reloc_status =
9234 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
9235 thumb_bit);
9236 break;
9237
9238 case elfcpp::R_ARM_ALU_PC_G0_NC:
9239 case elfcpp::R_ARM_ALU_PC_G0:
9240 case elfcpp::R_ARM_ALU_PC_G1_NC:
9241 case elfcpp::R_ARM_ALU_PC_G1:
9242 case elfcpp::R_ARM_ALU_PC_G2:
9243 case elfcpp::R_ARM_ALU_SB_G0_NC:
9244 case elfcpp::R_ARM_ALU_SB_G0:
9245 case elfcpp::R_ARM_ALU_SB_G1_NC:
9246 case elfcpp::R_ARM_ALU_SB_G1:
9247 case elfcpp::R_ARM_ALU_SB_G2:
9248 reloc_status =
9249 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
9250 reloc_property->group_index(),
9251 relative_address_base,
9252 thumb_bit, check_overflow);
9253 break;
9254
9255 case elfcpp::R_ARM_LDR_PC_G0:
9256 case elfcpp::R_ARM_LDR_PC_G1:
9257 case elfcpp::R_ARM_LDR_PC_G2:
9258 case elfcpp::R_ARM_LDR_SB_G0:
9259 case elfcpp::R_ARM_LDR_SB_G1:
9260 case elfcpp::R_ARM_LDR_SB_G2:
9261 reloc_status =
9262 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
9263 reloc_property->group_index(),
9264 relative_address_base);
9265 break;
9266
9267 case elfcpp::R_ARM_LDRS_PC_G0:
9268 case elfcpp::R_ARM_LDRS_PC_G1:
9269 case elfcpp::R_ARM_LDRS_PC_G2:
9270 case elfcpp::R_ARM_LDRS_SB_G0:
9271 case elfcpp::R_ARM_LDRS_SB_G1:
9272 case elfcpp::R_ARM_LDRS_SB_G2:
9273 reloc_status =
9274 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
9275 reloc_property->group_index(),
9276 relative_address_base);
9277 break;
9278
9279 case elfcpp::R_ARM_LDC_PC_G0:
9280 case elfcpp::R_ARM_LDC_PC_G1:
9281 case elfcpp::R_ARM_LDC_PC_G2:
9282 case elfcpp::R_ARM_LDC_SB_G0:
9283 case elfcpp::R_ARM_LDC_SB_G1:
9284 case elfcpp::R_ARM_LDC_SB_G2:
9285 reloc_status =
9286 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
9287 reloc_property->group_index(),
9288 relative_address_base);
9289 break;
9290
9291 // These are initial tls relocs, which are expected when
9292 // linking.
9293 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
9294 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
9295 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
9296 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
9297 case elfcpp::R_ARM_TLS_LE32: // Local-exec
9298 reloc_status =
9299 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
9300 view, address, view_size);
9301 break;
9302
9303 // The known and unknown unsupported and/or deprecated relocations.
9304 case elfcpp::R_ARM_PC24:
9305 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
9306 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
9307 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
9308 default:
9309 // Just silently leave the method. We should get an appropriate error
9310 // message in the scan methods.
9311 break;
9312 }
9313
9314 // Report any errors.
9315 switch (reloc_status)
9316 {
9317 case Arm_relocate_functions::STATUS_OKAY:
9318 break;
9319 case Arm_relocate_functions::STATUS_OVERFLOW:
9320 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
9321 _("relocation overflow in %s"),
9322 reloc_property->name().c_str());
9323 break;
9324 case Arm_relocate_functions::STATUS_BAD_RELOC:
9325 gold_error_at_location(
9326 relinfo,
9327 relnum,
9328 rel.get_r_offset(),
9329 _("unexpected opcode while processing relocation %s"),
9330 reloc_property->name().c_str());
9331 break;
9332 default:
9333 gold_unreachable();
9334 }
9335
9336 return true;
9337 }
9338
9339 // Perform a TLS relocation.
9340
9341 template<bool big_endian>
9342 inline typename Arm_relocate_functions<big_endian>::Status
9343 Target_arm<big_endian>::Relocate::relocate_tls(
9344 const Relocate_info<32, big_endian>* relinfo,
9345 Target_arm<big_endian>* target,
9346 size_t relnum,
9347 const elfcpp::Rel<32, big_endian>& rel,
9348 unsigned int r_type,
9349 const Sized_symbol<32>* gsym,
9350 const Symbol_value<32>* psymval,
9351 unsigned char* view,
9352 elfcpp::Elf_types<32>::Elf_Addr address,
9353 section_size_type /*view_size*/ )
9354 {
9355 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
9356 typedef Relocate_functions<32, big_endian> RelocFuncs;
9357 Output_segment* tls_segment = relinfo->layout->tls_segment();
9358
9359 const Sized_relobj_file<32, big_endian>* object = relinfo->object;
9360
9361 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
9362
9363 const bool is_final = (gsym == NULL
9364 ? !parameters->options().shared()
9365 : gsym->final_value_is_known());
9366 const tls::Tls_optimization optimized_type
9367 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
9368 switch (r_type)
9369 {
9370 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
9371 {
9372 unsigned int got_type = GOT_TYPE_TLS_PAIR;
9373 unsigned int got_offset;
9374 if (gsym != NULL)
9375 {
9376 gold_assert(gsym->has_got_offset(got_type));
9377 got_offset = gsym->got_offset(got_type) - target->got_size();
9378 }
9379 else
9380 {
9381 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9382 gold_assert(object->local_has_got_offset(r_sym, got_type));
9383 got_offset = (object->local_got_offset(r_sym, got_type)
9384 - target->got_size());
9385 }
9386 if (optimized_type == tls::TLSOPT_NONE)
9387 {
9388 Arm_address got_entry =
9389 target->got_plt_section()->address() + got_offset;
9390
9391 // Relocate the field with the PC relative offset of the pair of
9392 // GOT entries.
9393 RelocFuncs::pcrel32_unaligned(view, got_entry, address);
9394 return ArmRelocFuncs::STATUS_OKAY;
9395 }
9396 }
9397 break;
9398
9399 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
9400 if (optimized_type == tls::TLSOPT_NONE)
9401 {
9402 // Relocate the field with the offset of the GOT entry for
9403 // the module index.
9404 unsigned int got_offset;
9405 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
9406 - target->got_size());
9407 Arm_address got_entry =
9408 target->got_plt_section()->address() + got_offset;
9409
9410 // Relocate the field with the PC relative offset of the pair of
9411 // GOT entries.
9412 RelocFuncs::pcrel32_unaligned(view, got_entry, address);
9413 return ArmRelocFuncs::STATUS_OKAY;
9414 }
9415 break;
9416
9417 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
9418 RelocFuncs::rel32_unaligned(view, value);
9419 return ArmRelocFuncs::STATUS_OKAY;
9420
9421 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
9422 if (optimized_type == tls::TLSOPT_NONE)
9423 {
9424 // Relocate the field with the offset of the GOT entry for
9425 // the tp-relative offset of the symbol.
9426 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
9427 unsigned int got_offset;
9428 if (gsym != NULL)
9429 {
9430 gold_assert(gsym->has_got_offset(got_type));
9431 got_offset = gsym->got_offset(got_type);
9432 }
9433 else
9434 {
9435 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9436 gold_assert(object->local_has_got_offset(r_sym, got_type));
9437 got_offset = object->local_got_offset(r_sym, got_type);
9438 }
9439
9440 // All GOT offsets are relative to the end of the GOT.
9441 got_offset -= target->got_size();
9442
9443 Arm_address got_entry =
9444 target->got_plt_section()->address() + got_offset;
9445
9446 // Relocate the field with the PC relative offset of the GOT entry.
9447 RelocFuncs::pcrel32_unaligned(view, got_entry, address);
9448 return ArmRelocFuncs::STATUS_OKAY;
9449 }
9450 break;
9451
9452 case elfcpp::R_ARM_TLS_LE32: // Local-exec
9453 // If we're creating a shared library, a dynamic relocation will
9454 // have been created for this location, so do not apply it now.
9455 if (!parameters->options().shared())
9456 {
9457 gold_assert(tls_segment != NULL);
9458
9459 // $tp points to the TCB, which is followed by the TLS, so we
9460 // need to add TCB size to the offset.
9461 Arm_address aligned_tcb_size =
9462 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
9463 RelocFuncs::rel32_unaligned(view, value + aligned_tcb_size);
9464
9465 }
9466 return ArmRelocFuncs::STATUS_OKAY;
9467
9468 default:
9469 gold_unreachable();
9470 }
9471
9472 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
9473 _("unsupported reloc %u"),
9474 r_type);
9475 return ArmRelocFuncs::STATUS_BAD_RELOC;
9476 }
9477
9478 // Relocate section data.
9479
9480 template<bool big_endian>
9481 void
9482 Target_arm<big_endian>::relocate_section(
9483 const Relocate_info<32, big_endian>* relinfo,
9484 unsigned int sh_type,
9485 const unsigned char* prelocs,
9486 size_t reloc_count,
9487 Output_section* output_section,
9488 bool needs_special_offset_handling,
9489 unsigned char* view,
9490 Arm_address address,
9491 section_size_type view_size,
9492 const Reloc_symbol_changes* reloc_symbol_changes)
9493 {
9494 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
9495 gold_assert(sh_type == elfcpp::SHT_REL);
9496
9497 // See if we are relocating a relaxed input section. If so, the view
9498 // covers the whole output section and we need to adjust accordingly.
9499 if (needs_special_offset_handling)
9500 {
9501 const Output_relaxed_input_section* poris =
9502 output_section->find_relaxed_input_section(relinfo->object,
9503 relinfo->data_shndx);
9504 if (poris != NULL)
9505 {
9506 Arm_address section_address = poris->address();
9507 section_size_type section_size = poris->data_size();
9508
9509 gold_assert((section_address >= address)
9510 && ((section_address + section_size)
9511 <= (address + view_size)));
9512
9513 off_t offset = section_address - address;
9514 view += offset;
9515 address += offset;
9516 view_size = section_size;
9517 }
9518 }
9519
9520 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
9521 Arm_relocate>(
9522 relinfo,
9523 this,
9524 prelocs,
9525 reloc_count,
9526 output_section,
9527 needs_special_offset_handling,
9528 view,
9529 address,
9530 view_size,
9531 reloc_symbol_changes);
9532 }
9533
9534 // Return the size of a relocation while scanning during a relocatable
9535 // link.
9536
9537 template<bool big_endian>
9538 unsigned int
9539 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
9540 unsigned int r_type,
9541 Relobj* object)
9542 {
9543 r_type = get_real_reloc_type(r_type);
9544 const Arm_reloc_property* arp =
9545 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9546 if (arp != NULL)
9547 return arp->size();
9548 else
9549 {
9550 std::string reloc_name =
9551 arm_reloc_property_table->reloc_name_in_error_message(r_type);
9552 gold_error(_("%s: unexpected %s in object file"),
9553 object->name().c_str(), reloc_name.c_str());
9554 return 0;
9555 }
9556 }
9557
9558 // Scan the relocs during a relocatable link.
9559
9560 template<bool big_endian>
9561 void
9562 Target_arm<big_endian>::scan_relocatable_relocs(
9563 Symbol_table* symtab,
9564 Layout* layout,
9565 Sized_relobj_file<32, big_endian>* object,
9566 unsigned int data_shndx,
9567 unsigned int sh_type,
9568 const unsigned char* prelocs,
9569 size_t reloc_count,
9570 Output_section* output_section,
9571 bool needs_special_offset_handling,
9572 size_t local_symbol_count,
9573 const unsigned char* plocal_symbols,
9574 Relocatable_relocs* rr)
9575 {
9576 gold_assert(sh_type == elfcpp::SHT_REL);
9577
9578 typedef Arm_scan_relocatable_relocs<big_endian, elfcpp::SHT_REL,
9579 Relocatable_size_for_reloc> Scan_relocatable_relocs;
9580
9581 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
9582 Scan_relocatable_relocs>(
9583 symtab,
9584 layout,
9585 object,
9586 data_shndx,
9587 prelocs,
9588 reloc_count,
9589 output_section,
9590 needs_special_offset_handling,
9591 local_symbol_count,
9592 plocal_symbols,
9593 rr);
9594 }
9595
9596 // Emit relocations for a section.
9597
9598 template<bool big_endian>
9599 void
9600 Target_arm<big_endian>::relocate_relocs(
9601 const Relocate_info<32, big_endian>* relinfo,
9602 unsigned int sh_type,
9603 const unsigned char* prelocs,
9604 size_t reloc_count,
9605 Output_section* output_section,
9606 off_t offset_in_output_section,
9607 const Relocatable_relocs* rr,
9608 unsigned char* view,
9609 Arm_address view_address,
9610 section_size_type view_size,
9611 unsigned char* reloc_view,
9612 section_size_type reloc_view_size)
9613 {
9614 gold_assert(sh_type == elfcpp::SHT_REL);
9615
9616 gold::relocate_relocs<32, big_endian, elfcpp::SHT_REL>(
9617 relinfo,
9618 prelocs,
9619 reloc_count,
9620 output_section,
9621 offset_in_output_section,
9622 rr,
9623 view,
9624 view_address,
9625 view_size,
9626 reloc_view,
9627 reloc_view_size);
9628 }
9629
9630 // Perform target-specific processing in a relocatable link. This is
9631 // only used if we use the relocation strategy RELOC_SPECIAL.
9632
9633 template<bool big_endian>
9634 void
9635 Target_arm<big_endian>::relocate_special_relocatable(
9636 const Relocate_info<32, big_endian>* relinfo,
9637 unsigned int sh_type,
9638 const unsigned char* preloc_in,
9639 size_t relnum,
9640 Output_section* output_section,
9641 off_t offset_in_output_section,
9642 unsigned char* view,
9643 elfcpp::Elf_types<32>::Elf_Addr view_address,
9644 section_size_type,
9645 unsigned char* preloc_out)
9646 {
9647 // We can only handle REL type relocation sections.
9648 gold_assert(sh_type == elfcpp::SHT_REL);
9649
9650 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc Reltype;
9651 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc_write
9652 Reltype_write;
9653 const Arm_address invalid_address = static_cast<Arm_address>(0) - 1;
9654
9655 const Arm_relobj<big_endian>* object =
9656 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9657 const unsigned int local_count = object->local_symbol_count();
9658
9659 Reltype reloc(preloc_in);
9660 Reltype_write reloc_write(preloc_out);
9661
9662 elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
9663 const unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
9664 const unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
9665
9666 const Arm_reloc_property* arp =
9667 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9668 gold_assert(arp != NULL);
9669
9670 // Get the new symbol index.
9671 // We only use RELOC_SPECIAL strategy in local relocations.
9672 gold_assert(r_sym < local_count);
9673
9674 // We are adjusting a section symbol. We need to find
9675 // the symbol table index of the section symbol for
9676 // the output section corresponding to input section
9677 // in which this symbol is defined.
9678 bool is_ordinary;
9679 unsigned int shndx = object->local_symbol_input_shndx(r_sym, &is_ordinary);
9680 gold_assert(is_ordinary);
9681 Output_section* os = object->output_section(shndx);
9682 gold_assert(os != NULL);
9683 gold_assert(os->needs_symtab_index());
9684 unsigned int new_symndx = os->symtab_index();
9685
9686 // Get the new offset--the location in the output section where
9687 // this relocation should be applied.
9688
9689 Arm_address offset = reloc.get_r_offset();
9690 Arm_address new_offset;
9691 if (offset_in_output_section != invalid_address)
9692 new_offset = offset + offset_in_output_section;
9693 else
9694 {
9695 section_offset_type sot_offset =
9696 convert_types<section_offset_type, Arm_address>(offset);
9697 section_offset_type new_sot_offset =
9698 output_section->output_offset(object, relinfo->data_shndx,
9699 sot_offset);
9700 gold_assert(new_sot_offset != -1);
9701 new_offset = new_sot_offset;
9702 }
9703
9704 // In an object file, r_offset is an offset within the section.
9705 // In an executable or dynamic object, generated by
9706 // --emit-relocs, r_offset is an absolute address.
9707 if (!parameters->options().relocatable())
9708 {
9709 new_offset += view_address;
9710 if (offset_in_output_section != invalid_address)
9711 new_offset -= offset_in_output_section;
9712 }
9713
9714 reloc_write.put_r_offset(new_offset);
9715 reloc_write.put_r_info(elfcpp::elf_r_info<32>(new_symndx, r_type));
9716
9717 // Handle the reloc addend.
9718 // The relocation uses a section symbol in the input file.
9719 // We are adjusting it to use a section symbol in the output
9720 // file. The input section symbol refers to some address in
9721 // the input section. We need the relocation in the output
9722 // file to refer to that same address. This adjustment to
9723 // the addend is the same calculation we use for a simple
9724 // absolute relocation for the input section symbol.
9725
9726 const Symbol_value<32>* psymval = object->local_symbol(r_sym);
9727
9728 // Handle THUMB bit.
9729 Symbol_value<32> symval;
9730 Arm_address thumb_bit =
9731 object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
9732 if (thumb_bit != 0
9733 && arp->uses_thumb_bit()
9734 && ((psymval->value(object, 0) & 1) != 0))
9735 {
9736 Arm_address stripped_value =
9737 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
9738 symval.set_output_value(stripped_value);
9739 psymval = &symval;
9740 }
9741
9742 unsigned char* paddend = view + offset;
9743 typename Arm_relocate_functions<big_endian>::Status reloc_status =
9744 Arm_relocate_functions<big_endian>::STATUS_OKAY;
9745 switch (r_type)
9746 {
9747 case elfcpp::R_ARM_ABS8:
9748 reloc_status = Arm_relocate_functions<big_endian>::abs8(paddend, object,
9749 psymval);
9750 break;
9751
9752 case elfcpp::R_ARM_ABS12:
9753 reloc_status = Arm_relocate_functions<big_endian>::abs12(paddend, object,
9754 psymval);
9755 break;
9756
9757 case elfcpp::R_ARM_ABS16:
9758 reloc_status = Arm_relocate_functions<big_endian>::abs16(paddend, object,
9759 psymval);
9760 break;
9761
9762 case elfcpp::R_ARM_THM_ABS5:
9763 reloc_status = Arm_relocate_functions<big_endian>::thm_abs5(paddend,
9764 object,
9765 psymval);
9766 break;
9767
9768 case elfcpp::R_ARM_MOVW_ABS_NC:
9769 case elfcpp::R_ARM_MOVW_PREL_NC:
9770 case elfcpp::R_ARM_MOVW_BREL_NC:
9771 case elfcpp::R_ARM_MOVW_BREL:
9772 reloc_status = Arm_relocate_functions<big_endian>::movw(
9773 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9774 break;
9775
9776 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
9777 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
9778 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
9779 case elfcpp::R_ARM_THM_MOVW_BREL:
9780 reloc_status = Arm_relocate_functions<big_endian>::thm_movw(
9781 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9782 break;
9783
9784 case elfcpp::R_ARM_THM_CALL:
9785 case elfcpp::R_ARM_THM_XPC22:
9786 case elfcpp::R_ARM_THM_JUMP24:
9787 reloc_status =
9788 Arm_relocate_functions<big_endian>::thumb_branch_common(
9789 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9790 false);
9791 break;
9792
9793 case elfcpp::R_ARM_PLT32:
9794 case elfcpp::R_ARM_CALL:
9795 case elfcpp::R_ARM_JUMP24:
9796 case elfcpp::R_ARM_XPC25:
9797 reloc_status =
9798 Arm_relocate_functions<big_endian>::arm_branch_common(
9799 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9800 false);
9801 break;
9802
9803 case elfcpp::R_ARM_THM_JUMP19:
9804 reloc_status =
9805 Arm_relocate_functions<big_endian>::thm_jump19(paddend, object,
9806 psymval, 0, thumb_bit);
9807 break;
9808
9809 case elfcpp::R_ARM_THM_JUMP6:
9810 reloc_status =
9811 Arm_relocate_functions<big_endian>::thm_jump6(paddend, object, psymval,
9812 0);
9813 break;
9814
9815 case elfcpp::R_ARM_THM_JUMP8:
9816 reloc_status =
9817 Arm_relocate_functions<big_endian>::thm_jump8(paddend, object, psymval,
9818 0);
9819 break;
9820
9821 case elfcpp::R_ARM_THM_JUMP11:
9822 reloc_status =
9823 Arm_relocate_functions<big_endian>::thm_jump11(paddend, object, psymval,
9824 0);
9825 break;
9826
9827 case elfcpp::R_ARM_PREL31:
9828 reloc_status =
9829 Arm_relocate_functions<big_endian>::prel31(paddend, object, psymval, 0,
9830 thumb_bit);
9831 break;
9832
9833 case elfcpp::R_ARM_THM_PC8:
9834 reloc_status =
9835 Arm_relocate_functions<big_endian>::thm_pc8(paddend, object, psymval,
9836 0);
9837 break;
9838
9839 case elfcpp::R_ARM_THM_PC12:
9840 reloc_status =
9841 Arm_relocate_functions<big_endian>::thm_pc12(paddend, object, psymval,
9842 0);
9843 break;
9844
9845 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
9846 reloc_status =
9847 Arm_relocate_functions<big_endian>::thm_alu11(paddend, object, psymval,
9848 0, thumb_bit);
9849 break;
9850
9851 // These relocation truncate relocation results so we cannot handle them
9852 // in a relocatable link.
9853 case elfcpp::R_ARM_MOVT_ABS:
9854 case elfcpp::R_ARM_THM_MOVT_ABS:
9855 case elfcpp::R_ARM_MOVT_PREL:
9856 case elfcpp::R_ARM_MOVT_BREL:
9857 case elfcpp::R_ARM_THM_MOVT_PREL:
9858 case elfcpp::R_ARM_THM_MOVT_BREL:
9859 case elfcpp::R_ARM_ALU_PC_G0_NC:
9860 case elfcpp::R_ARM_ALU_PC_G0:
9861 case elfcpp::R_ARM_ALU_PC_G1_NC:
9862 case elfcpp::R_ARM_ALU_PC_G1:
9863 case elfcpp::R_ARM_ALU_PC_G2:
9864 case elfcpp::R_ARM_ALU_SB_G0_NC:
9865 case elfcpp::R_ARM_ALU_SB_G0:
9866 case elfcpp::R_ARM_ALU_SB_G1_NC:
9867 case elfcpp::R_ARM_ALU_SB_G1:
9868 case elfcpp::R_ARM_ALU_SB_G2:
9869 case elfcpp::R_ARM_LDR_PC_G0:
9870 case elfcpp::R_ARM_LDR_PC_G1:
9871 case elfcpp::R_ARM_LDR_PC_G2:
9872 case elfcpp::R_ARM_LDR_SB_G0:
9873 case elfcpp::R_ARM_LDR_SB_G1:
9874 case elfcpp::R_ARM_LDR_SB_G2:
9875 case elfcpp::R_ARM_LDRS_PC_G0:
9876 case elfcpp::R_ARM_LDRS_PC_G1:
9877 case elfcpp::R_ARM_LDRS_PC_G2:
9878 case elfcpp::R_ARM_LDRS_SB_G0:
9879 case elfcpp::R_ARM_LDRS_SB_G1:
9880 case elfcpp::R_ARM_LDRS_SB_G2:
9881 case elfcpp::R_ARM_LDC_PC_G0:
9882 case elfcpp::R_ARM_LDC_PC_G1:
9883 case elfcpp::R_ARM_LDC_PC_G2:
9884 case elfcpp::R_ARM_LDC_SB_G0:
9885 case elfcpp::R_ARM_LDC_SB_G1:
9886 case elfcpp::R_ARM_LDC_SB_G2:
9887 gold_error(_("cannot handle %s in a relocatable link"),
9888 arp->name().c_str());
9889 break;
9890
9891 default:
9892 gold_unreachable();
9893 }
9894
9895 // Report any errors.
9896 switch (reloc_status)
9897 {
9898 case Arm_relocate_functions<big_endian>::STATUS_OKAY:
9899 break;
9900 case Arm_relocate_functions<big_endian>::STATUS_OVERFLOW:
9901 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9902 _("relocation overflow in %s"),
9903 arp->name().c_str());
9904 break;
9905 case Arm_relocate_functions<big_endian>::STATUS_BAD_RELOC:
9906 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9907 _("unexpected opcode while processing relocation %s"),
9908 arp->name().c_str());
9909 break;
9910 default:
9911 gold_unreachable();
9912 }
9913 }
9914
9915 // Return the value to use for a dynamic symbol which requires special
9916 // treatment. This is how we support equality comparisons of function
9917 // pointers across shared library boundaries, as described in the
9918 // processor specific ABI supplement.
9919
9920 template<bool big_endian>
9921 uint64_t
9922 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
9923 {
9924 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
9925 return this->plt_section()->address() + gsym->plt_offset();
9926 }
9927
9928 // Map platform-specific relocs to real relocs
9929 //
9930 template<bool big_endian>
9931 unsigned int
9932 Target_arm<big_endian>::get_real_reloc_type(unsigned int r_type)
9933 {
9934 switch (r_type)
9935 {
9936 case elfcpp::R_ARM_TARGET1:
9937 // This is either R_ARM_ABS32 or R_ARM_REL32;
9938 return elfcpp::R_ARM_ABS32;
9939
9940 case elfcpp::R_ARM_TARGET2:
9941 // This can be any reloc type but usually is R_ARM_GOT_PREL
9942 return elfcpp::R_ARM_GOT_PREL;
9943
9944 default:
9945 return r_type;
9946 }
9947 }
9948
9949 // Whether if two EABI versions V1 and V2 are compatible.
9950
9951 template<bool big_endian>
9952 bool
9953 Target_arm<big_endian>::are_eabi_versions_compatible(
9954 elfcpp::Elf_Word v1,
9955 elfcpp::Elf_Word v2)
9956 {
9957 // v4 and v5 are the same spec before and after it was released,
9958 // so allow mixing them.
9959 if ((v1 == elfcpp::EF_ARM_EABI_UNKNOWN || v2 == elfcpp::EF_ARM_EABI_UNKNOWN)
9960 || (v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
9961 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
9962 return true;
9963
9964 return v1 == v2;
9965 }
9966
9967 // Combine FLAGS from an input object called NAME and the processor-specific
9968 // flags in the ELF header of the output. Much of this is adapted from the
9969 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
9970 // in bfd/elf32-arm.c.
9971
9972 template<bool big_endian>
9973 void
9974 Target_arm<big_endian>::merge_processor_specific_flags(
9975 const std::string& name,
9976 elfcpp::Elf_Word flags)
9977 {
9978 if (this->are_processor_specific_flags_set())
9979 {
9980 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
9981
9982 // Nothing to merge if flags equal to those in output.
9983 if (flags == out_flags)
9984 return;
9985
9986 // Complain about various flag mismatches.
9987 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
9988 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
9989 if (!this->are_eabi_versions_compatible(version1, version2)
9990 && parameters->options().warn_mismatch())
9991 gold_error(_("Source object %s has EABI version %d but output has "
9992 "EABI version %d."),
9993 name.c_str(),
9994 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
9995 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
9996 }
9997 else
9998 {
9999 // If the input is the default architecture and had the default
10000 // flags then do not bother setting the flags for the output
10001 // architecture, instead allow future merges to do this. If no
10002 // future merges ever set these flags then they will retain their
10003 // uninitialised values, which surprise surprise, correspond
10004 // to the default values.
10005 if (flags == 0)
10006 return;
10007
10008 // This is the first time, just copy the flags.
10009 // We only copy the EABI version for now.
10010 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
10011 }
10012 }
10013
10014 // Adjust ELF file header.
10015 template<bool big_endian>
10016 void
10017 Target_arm<big_endian>::do_adjust_elf_header(
10018 unsigned char* view,
10019 int len) const
10020 {
10021 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
10022
10023 elfcpp::Ehdr<32, big_endian> ehdr(view);
10024 unsigned char e_ident[elfcpp::EI_NIDENT];
10025 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
10026
10027 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
10028 == elfcpp::EF_ARM_EABI_UNKNOWN)
10029 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
10030 else
10031 e_ident[elfcpp::EI_OSABI] = 0;
10032 e_ident[elfcpp::EI_ABIVERSION] = 0;
10033
10034 // FIXME: Do EF_ARM_BE8 adjustment.
10035
10036 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
10037 oehdr.put_e_ident(e_ident);
10038 }
10039
10040 // do_make_elf_object to override the same function in the base class.
10041 // We need to use a target-specific sub-class of
10042 // Sized_relobj_file<32, big_endian> to store ARM specific information.
10043 // Hence we need to have our own ELF object creation.
10044
10045 template<bool big_endian>
10046 Object*
10047 Target_arm<big_endian>::do_make_elf_object(
10048 const std::string& name,
10049 Input_file* input_file,
10050 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
10051 {
10052 int et = ehdr.get_e_type();
10053 // ET_EXEC files are valid input for --just-symbols/-R,
10054 // and we treat them as relocatable objects.
10055 if (et == elfcpp::ET_REL
10056 || (et == elfcpp::ET_EXEC && input_file->just_symbols()))
10057 {
10058 Arm_relobj<big_endian>* obj =
10059 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
10060 obj->setup();
10061 return obj;
10062 }
10063 else if (et == elfcpp::ET_DYN)
10064 {
10065 Sized_dynobj<32, big_endian>* obj =
10066 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
10067 obj->setup();
10068 return obj;
10069 }
10070 else
10071 {
10072 gold_error(_("%s: unsupported ELF file type %d"),
10073 name.c_str(), et);
10074 return NULL;
10075 }
10076 }
10077
10078 // Read the architecture from the Tag_also_compatible_with attribute, if any.
10079 // Returns -1 if no architecture could be read.
10080 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
10081
10082 template<bool big_endian>
10083 int
10084 Target_arm<big_endian>::get_secondary_compatible_arch(
10085 const Attributes_section_data* pasd)
10086 {
10087 const Object_attribute* known_attributes =
10088 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
10089
10090 // Note: the tag and its argument below are uleb128 values, though
10091 // currently-defined values fit in one byte for each.
10092 const std::string& sv =
10093 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
10094 if (sv.size() == 2
10095 && sv.data()[0] == elfcpp::Tag_CPU_arch
10096 && (sv.data()[1] & 128) != 128)
10097 return sv.data()[1];
10098
10099 // This tag is "safely ignorable", so don't complain if it looks funny.
10100 return -1;
10101 }
10102
10103 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
10104 // The tag is removed if ARCH is -1.
10105 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
10106
10107 template<bool big_endian>
10108 void
10109 Target_arm<big_endian>::set_secondary_compatible_arch(
10110 Attributes_section_data* pasd,
10111 int arch)
10112 {
10113 Object_attribute* known_attributes =
10114 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
10115
10116 if (arch == -1)
10117 {
10118 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
10119 return;
10120 }
10121
10122 // Note: the tag and its argument below are uleb128 values, though
10123 // currently-defined values fit in one byte for each.
10124 char sv[3];
10125 sv[0] = elfcpp::Tag_CPU_arch;
10126 gold_assert(arch != 0);
10127 sv[1] = arch;
10128 sv[2] = '\0';
10129
10130 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
10131 }
10132
10133 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
10134 // into account.
10135 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
10136
10137 template<bool big_endian>
10138 int
10139 Target_arm<big_endian>::tag_cpu_arch_combine(
10140 const char* name,
10141 int oldtag,
10142 int* secondary_compat_out,
10143 int newtag,
10144 int secondary_compat)
10145 {
10146 #define T(X) elfcpp::TAG_CPU_ARCH_##X
10147 static const int v6t2[] =
10148 {
10149 T(V6T2), // PRE_V4.
10150 T(V6T2), // V4.
10151 T(V6T2), // V4T.
10152 T(V6T2), // V5T.
10153 T(V6T2), // V5TE.
10154 T(V6T2), // V5TEJ.
10155 T(V6T2), // V6.
10156 T(V7), // V6KZ.
10157 T(V6T2) // V6T2.
10158 };
10159 static const int v6k[] =
10160 {
10161 T(V6K), // PRE_V4.
10162 T(V6K), // V4.
10163 T(V6K), // V4T.
10164 T(V6K), // V5T.
10165 T(V6K), // V5TE.
10166 T(V6K), // V5TEJ.
10167 T(V6K), // V6.
10168 T(V6KZ), // V6KZ.
10169 T(V7), // V6T2.
10170 T(V6K) // V6K.
10171 };
10172 static const int v7[] =
10173 {
10174 T(V7), // PRE_V4.
10175 T(V7), // V4.
10176 T(V7), // V4T.
10177 T(V7), // V5T.
10178 T(V7), // V5TE.
10179 T(V7), // V5TEJ.
10180 T(V7), // V6.
10181 T(V7), // V6KZ.
10182 T(V7), // V6T2.
10183 T(V7), // V6K.
10184 T(V7) // V7.
10185 };
10186 static const int v6_m[] =
10187 {
10188 -1, // PRE_V4.
10189 -1, // V4.
10190 T(V6K), // V4T.
10191 T(V6K), // V5T.
10192 T(V6K), // V5TE.
10193 T(V6K), // V5TEJ.
10194 T(V6K), // V6.
10195 T(V6KZ), // V6KZ.
10196 T(V7), // V6T2.
10197 T(V6K), // V6K.
10198 T(V7), // V7.
10199 T(V6_M) // V6_M.
10200 };
10201 static const int v6s_m[] =
10202 {
10203 -1, // PRE_V4.
10204 -1, // V4.
10205 T(V6K), // V4T.
10206 T(V6K), // V5T.
10207 T(V6K), // V5TE.
10208 T(V6K), // V5TEJ.
10209 T(V6K), // V6.
10210 T(V6KZ), // V6KZ.
10211 T(V7), // V6T2.
10212 T(V6K), // V6K.
10213 T(V7), // V7.
10214 T(V6S_M), // V6_M.
10215 T(V6S_M) // V6S_M.
10216 };
10217 static const int v7e_m[] =
10218 {
10219 -1, // PRE_V4.
10220 -1, // V4.
10221 T(V7E_M), // V4T.
10222 T(V7E_M), // V5T.
10223 T(V7E_M), // V5TE.
10224 T(V7E_M), // V5TEJ.
10225 T(V7E_M), // V6.
10226 T(V7E_M), // V6KZ.
10227 T(V7E_M), // V6T2.
10228 T(V7E_M), // V6K.
10229 T(V7E_M), // V7.
10230 T(V7E_M), // V6_M.
10231 T(V7E_M), // V6S_M.
10232 T(V7E_M) // V7E_M.
10233 };
10234 static const int v4t_plus_v6_m[] =
10235 {
10236 -1, // PRE_V4.
10237 -1, // V4.
10238 T(V4T), // V4T.
10239 T(V5T), // V5T.
10240 T(V5TE), // V5TE.
10241 T(V5TEJ), // V5TEJ.
10242 T(V6), // V6.
10243 T(V6KZ), // V6KZ.
10244 T(V6T2), // V6T2.
10245 T(V6K), // V6K.
10246 T(V7), // V7.
10247 T(V6_M), // V6_M.
10248 T(V6S_M), // V6S_M.
10249 T(V7E_M), // V7E_M.
10250 T(V4T_PLUS_V6_M) // V4T plus V6_M.
10251 };
10252 static const int* comb[] =
10253 {
10254 v6t2,
10255 v6k,
10256 v7,
10257 v6_m,
10258 v6s_m,
10259 v7e_m,
10260 // Pseudo-architecture.
10261 v4t_plus_v6_m
10262 };
10263
10264 // Check we've not got a higher architecture than we know about.
10265
10266 if (oldtag > elfcpp::MAX_TAG_CPU_ARCH || newtag > elfcpp::MAX_TAG_CPU_ARCH)
10267 {
10268 gold_error(_("%s: unknown CPU architecture"), name);
10269 return -1;
10270 }
10271
10272 // Override old tag if we have a Tag_also_compatible_with on the output.
10273
10274 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
10275 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
10276 oldtag = T(V4T_PLUS_V6_M);
10277
10278 // And override the new tag if we have a Tag_also_compatible_with on the
10279 // input.
10280
10281 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
10282 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
10283 newtag = T(V4T_PLUS_V6_M);
10284
10285 // Architectures before V6KZ add features monotonically.
10286 int tagh = std::max(oldtag, newtag);
10287 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
10288 return tagh;
10289
10290 int tagl = std::min(oldtag, newtag);
10291 int result = comb[tagh - T(V6T2)][tagl];
10292
10293 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
10294 // as the canonical version.
10295 if (result == T(V4T_PLUS_V6_M))
10296 {
10297 result = T(V4T);
10298 *secondary_compat_out = T(V6_M);
10299 }
10300 else
10301 *secondary_compat_out = -1;
10302
10303 if (result == -1)
10304 {
10305 gold_error(_("%s: conflicting CPU architectures %d/%d"),
10306 name, oldtag, newtag);
10307 return -1;
10308 }
10309
10310 return result;
10311 #undef T
10312 }
10313
10314 // Helper to print AEABI enum tag value.
10315
10316 template<bool big_endian>
10317 std::string
10318 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
10319 {
10320 static const char* aeabi_enum_names[] =
10321 { "", "variable-size", "32-bit", "" };
10322 const size_t aeabi_enum_names_size =
10323 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
10324
10325 if (value < aeabi_enum_names_size)
10326 return std::string(aeabi_enum_names[value]);
10327 else
10328 {
10329 char buffer[100];
10330 sprintf(buffer, "<unknown value %u>", value);
10331 return std::string(buffer);
10332 }
10333 }
10334
10335 // Return the string value to store in TAG_CPU_name.
10336
10337 template<bool big_endian>
10338 std::string
10339 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
10340 {
10341 static const char* name_table[] = {
10342 // These aren't real CPU names, but we can't guess
10343 // that from the architecture version alone.
10344 "Pre v4",
10345 "ARM v4",
10346 "ARM v4T",
10347 "ARM v5T",
10348 "ARM v5TE",
10349 "ARM v5TEJ",
10350 "ARM v6",
10351 "ARM v6KZ",
10352 "ARM v6T2",
10353 "ARM v6K",
10354 "ARM v7",
10355 "ARM v6-M",
10356 "ARM v6S-M",
10357 "ARM v7E-M"
10358 };
10359 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
10360
10361 if (value < name_table_size)
10362 return std::string(name_table[value]);
10363 else
10364 {
10365 char buffer[100];
10366 sprintf(buffer, "<unknown CPU value %u>", value);
10367 return std::string(buffer);
10368 }
10369 }
10370
10371 // Merge object attributes from input file called NAME with those of the
10372 // output. The input object attributes are in the object pointed by PASD.
10373
10374 template<bool big_endian>
10375 void
10376 Target_arm<big_endian>::merge_object_attributes(
10377 const char* name,
10378 const Attributes_section_data* pasd)
10379 {
10380 // Return if there is no attributes section data.
10381 if (pasd == NULL)
10382 return;
10383
10384 // If output has no object attributes, just copy.
10385 const int vendor = Object_attribute::OBJ_ATTR_PROC;
10386 if (this->attributes_section_data_ == NULL)
10387 {
10388 this->attributes_section_data_ = new Attributes_section_data(*pasd);
10389 Object_attribute* out_attr =
10390 this->attributes_section_data_->known_attributes(vendor);
10391
10392 // We do not output objects with Tag_MPextension_use_legacy - we move
10393 // the attribute's value to Tag_MPextension_use. */
10394 if (out_attr[elfcpp::Tag_MPextension_use_legacy].int_value() != 0)
10395 {
10396 if (out_attr[elfcpp::Tag_MPextension_use].int_value() != 0
10397 && out_attr[elfcpp::Tag_MPextension_use_legacy].int_value()
10398 != out_attr[elfcpp::Tag_MPextension_use].int_value())
10399 {
10400 gold_error(_("%s has both the current and legacy "
10401 "Tag_MPextension_use attributes"),
10402 name);
10403 }
10404
10405 out_attr[elfcpp::Tag_MPextension_use] =
10406 out_attr[elfcpp::Tag_MPextension_use_legacy];
10407 out_attr[elfcpp::Tag_MPextension_use_legacy].set_type(0);
10408 out_attr[elfcpp::Tag_MPextension_use_legacy].set_int_value(0);
10409 }
10410
10411 return;
10412 }
10413
10414 const Object_attribute* in_attr = pasd->known_attributes(vendor);
10415 Object_attribute* out_attr =
10416 this->attributes_section_data_->known_attributes(vendor);
10417
10418 // This needs to happen before Tag_ABI_FP_number_model is merged. */
10419 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
10420 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
10421 {
10422 // Ignore mismatches if the object doesn't use floating point. */
10423 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
10424 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
10425 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
10426 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0
10427 && parameters->options().warn_mismatch())
10428 gold_error(_("%s uses VFP register arguments, output does not"),
10429 name);
10430 }
10431
10432 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
10433 {
10434 // Merge this attribute with existing attributes.
10435 switch (i)
10436 {
10437 case elfcpp::Tag_CPU_raw_name:
10438 case elfcpp::Tag_CPU_name:
10439 // These are merged after Tag_CPU_arch.
10440 break;
10441
10442 case elfcpp::Tag_ABI_optimization_goals:
10443 case elfcpp::Tag_ABI_FP_optimization_goals:
10444 // Use the first value seen.
10445 break;
10446
10447 case elfcpp::Tag_CPU_arch:
10448 {
10449 unsigned int saved_out_attr = out_attr->int_value();
10450 // Merge Tag_CPU_arch and Tag_also_compatible_with.
10451 int secondary_compat =
10452 this->get_secondary_compatible_arch(pasd);
10453 int secondary_compat_out =
10454 this->get_secondary_compatible_arch(
10455 this->attributes_section_data_);
10456 out_attr[i].set_int_value(
10457 tag_cpu_arch_combine(name, out_attr[i].int_value(),
10458 &secondary_compat_out,
10459 in_attr[i].int_value(),
10460 secondary_compat));
10461 this->set_secondary_compatible_arch(this->attributes_section_data_,
10462 secondary_compat_out);
10463
10464 // Merge Tag_CPU_name and Tag_CPU_raw_name.
10465 if (out_attr[i].int_value() == saved_out_attr)
10466 ; // Leave the names alone.
10467 else if (out_attr[i].int_value() == in_attr[i].int_value())
10468 {
10469 // The output architecture has been changed to match the
10470 // input architecture. Use the input names.
10471 out_attr[elfcpp::Tag_CPU_name].set_string_value(
10472 in_attr[elfcpp::Tag_CPU_name].string_value());
10473 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
10474 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
10475 }
10476 else
10477 {
10478 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
10479 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
10480 }
10481
10482 // If we still don't have a value for Tag_CPU_name,
10483 // make one up now. Tag_CPU_raw_name remains blank.
10484 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
10485 {
10486 const std::string cpu_name =
10487 this->tag_cpu_name_value(out_attr[i].int_value());
10488 // FIXME: If we see an unknown CPU, this will be set
10489 // to "<unknown CPU n>", where n is the attribute value.
10490 // This is different from BFD, which leaves the name alone.
10491 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
10492 }
10493 }
10494 break;
10495
10496 case elfcpp::Tag_ARM_ISA_use:
10497 case elfcpp::Tag_THUMB_ISA_use:
10498 case elfcpp::Tag_WMMX_arch:
10499 case elfcpp::Tag_Advanced_SIMD_arch:
10500 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
10501 case elfcpp::Tag_ABI_FP_rounding:
10502 case elfcpp::Tag_ABI_FP_exceptions:
10503 case elfcpp::Tag_ABI_FP_user_exceptions:
10504 case elfcpp::Tag_ABI_FP_number_model:
10505 case elfcpp::Tag_VFP_HP_extension:
10506 case elfcpp::Tag_CPU_unaligned_access:
10507 case elfcpp::Tag_T2EE_use:
10508 case elfcpp::Tag_Virtualization_use:
10509 case elfcpp::Tag_MPextension_use:
10510 // Use the largest value specified.
10511 if (in_attr[i].int_value() > out_attr[i].int_value())
10512 out_attr[i].set_int_value(in_attr[i].int_value());
10513 break;
10514
10515 case elfcpp::Tag_ABI_align8_preserved:
10516 case elfcpp::Tag_ABI_PCS_RO_data:
10517 // Use the smallest value specified.
10518 if (in_attr[i].int_value() < out_attr[i].int_value())
10519 out_attr[i].set_int_value(in_attr[i].int_value());
10520 break;
10521
10522 case elfcpp::Tag_ABI_align8_needed:
10523 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
10524 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
10525 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
10526 == 0)))
10527 {
10528 // This error message should be enabled once all non-conforming
10529 // binaries in the toolchain have had the attributes set
10530 // properly.
10531 // gold_error(_("output 8-byte data alignment conflicts with %s"),
10532 // name);
10533 }
10534 // Fall through.
10535 case elfcpp::Tag_ABI_FP_denormal:
10536 case elfcpp::Tag_ABI_PCS_GOT_use:
10537 {
10538 // These tags have 0 = don't care, 1 = strong requirement,
10539 // 2 = weak requirement.
10540 static const int order_021[3] = {0, 2, 1};
10541
10542 // Use the "greatest" from the sequence 0, 2, 1, or the largest
10543 // value if greater than 2 (for future-proofing).
10544 if ((in_attr[i].int_value() > 2
10545 && in_attr[i].int_value() > out_attr[i].int_value())
10546 || (in_attr[i].int_value() <= 2
10547 && out_attr[i].int_value() <= 2
10548 && (order_021[in_attr[i].int_value()]
10549 > order_021[out_attr[i].int_value()])))
10550 out_attr[i].set_int_value(in_attr[i].int_value());
10551 }
10552 break;
10553
10554 case elfcpp::Tag_CPU_arch_profile:
10555 if (out_attr[i].int_value() != in_attr[i].int_value())
10556 {
10557 // 0 will merge with anything.
10558 // 'A' and 'S' merge to 'A'.
10559 // 'R' and 'S' merge to 'R'.
10560 // 'M' and 'A|R|S' is an error.
10561 if (out_attr[i].int_value() == 0
10562 || (out_attr[i].int_value() == 'S'
10563 && (in_attr[i].int_value() == 'A'
10564 || in_attr[i].int_value() == 'R')))
10565 out_attr[i].set_int_value(in_attr[i].int_value());
10566 else if (in_attr[i].int_value() == 0
10567 || (in_attr[i].int_value() == 'S'
10568 && (out_attr[i].int_value() == 'A'
10569 || out_attr[i].int_value() == 'R')))
10570 ; // Do nothing.
10571 else if (parameters->options().warn_mismatch())
10572 {
10573 gold_error
10574 (_("conflicting architecture profiles %c/%c"),
10575 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
10576 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
10577 }
10578 }
10579 break;
10580 case elfcpp::Tag_VFP_arch:
10581 {
10582 static const struct
10583 {
10584 int ver;
10585 int regs;
10586 } vfp_versions[7] =
10587 {
10588 {0, 0},
10589 {1, 16},
10590 {2, 16},
10591 {3, 32},
10592 {3, 16},
10593 {4, 32},
10594 {4, 16}
10595 };
10596
10597 // Values greater than 6 aren't defined, so just pick the
10598 // biggest.
10599 if (in_attr[i].int_value() > 6
10600 && in_attr[i].int_value() > out_attr[i].int_value())
10601 {
10602 *out_attr = *in_attr;
10603 break;
10604 }
10605 // The output uses the superset of input features
10606 // (ISA version) and registers.
10607 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
10608 vfp_versions[out_attr[i].int_value()].ver);
10609 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
10610 vfp_versions[out_attr[i].int_value()].regs);
10611 // This assumes all possible supersets are also a valid
10612 // options.
10613 int newval;
10614 for (newval = 6; newval > 0; newval--)
10615 {
10616 if (regs == vfp_versions[newval].regs
10617 && ver == vfp_versions[newval].ver)
10618 break;
10619 }
10620 out_attr[i].set_int_value(newval);
10621 }
10622 break;
10623 case elfcpp::Tag_PCS_config:
10624 if (out_attr[i].int_value() == 0)
10625 out_attr[i].set_int_value(in_attr[i].int_value());
10626 else if (in_attr[i].int_value() != 0
10627 && out_attr[i].int_value() != 0
10628 && parameters->options().warn_mismatch())
10629 {
10630 // It's sometimes ok to mix different configs, so this is only
10631 // a warning.
10632 gold_warning(_("%s: conflicting platform configuration"), name);
10633 }
10634 break;
10635 case elfcpp::Tag_ABI_PCS_R9_use:
10636 if (in_attr[i].int_value() != out_attr[i].int_value()
10637 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
10638 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused
10639 && parameters->options().warn_mismatch())
10640 {
10641 gold_error(_("%s: conflicting use of R9"), name);
10642 }
10643 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
10644 out_attr[i].set_int_value(in_attr[i].int_value());
10645 break;
10646 case elfcpp::Tag_ABI_PCS_RW_data:
10647 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
10648 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10649 != elfcpp::AEABI_R9_SB)
10650 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10651 != elfcpp::AEABI_R9_unused)
10652 && parameters->options().warn_mismatch())
10653 {
10654 gold_error(_("%s: SB relative addressing conflicts with use "
10655 "of R9"),
10656 name);
10657 }
10658 // Use the smallest value specified.
10659 if (in_attr[i].int_value() < out_attr[i].int_value())
10660 out_attr[i].set_int_value(in_attr[i].int_value());
10661 break;
10662 case elfcpp::Tag_ABI_PCS_wchar_t:
10663 if (out_attr[i].int_value()
10664 && in_attr[i].int_value()
10665 && out_attr[i].int_value() != in_attr[i].int_value()
10666 && parameters->options().warn_mismatch()
10667 && parameters->options().wchar_size_warning())
10668 {
10669 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
10670 "use %u-byte wchar_t; use of wchar_t values "
10671 "across objects may fail"),
10672 name, in_attr[i].int_value(),
10673 out_attr[i].int_value());
10674 }
10675 else if (in_attr[i].int_value() && !out_attr[i].int_value())
10676 out_attr[i].set_int_value(in_attr[i].int_value());
10677 break;
10678 case elfcpp::Tag_ABI_enum_size:
10679 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
10680 {
10681 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
10682 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
10683 {
10684 // The existing object is compatible with anything.
10685 // Use whatever requirements the new object has.
10686 out_attr[i].set_int_value(in_attr[i].int_value());
10687 }
10688 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
10689 && out_attr[i].int_value() != in_attr[i].int_value()
10690 && parameters->options().warn_mismatch()
10691 && parameters->options().enum_size_warning())
10692 {
10693 unsigned int in_value = in_attr[i].int_value();
10694 unsigned int out_value = out_attr[i].int_value();
10695 gold_warning(_("%s uses %s enums yet the output is to use "
10696 "%s enums; use of enum values across objects "
10697 "may fail"),
10698 name,
10699 this->aeabi_enum_name(in_value).c_str(),
10700 this->aeabi_enum_name(out_value).c_str());
10701 }
10702 }
10703 break;
10704 case elfcpp::Tag_ABI_VFP_args:
10705 // Already done.
10706 break;
10707 case elfcpp::Tag_ABI_WMMX_args:
10708 if (in_attr[i].int_value() != out_attr[i].int_value()
10709 && parameters->options().warn_mismatch())
10710 {
10711 gold_error(_("%s uses iWMMXt register arguments, output does "
10712 "not"),
10713 name);
10714 }
10715 break;
10716 case Object_attribute::Tag_compatibility:
10717 // Merged in target-independent code.
10718 break;
10719 case elfcpp::Tag_ABI_HardFP_use:
10720 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
10721 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
10722 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
10723 out_attr[i].set_int_value(3);
10724 else if (in_attr[i].int_value() > out_attr[i].int_value())
10725 out_attr[i].set_int_value(in_attr[i].int_value());
10726 break;
10727 case elfcpp::Tag_ABI_FP_16bit_format:
10728 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
10729 {
10730 if (in_attr[i].int_value() != out_attr[i].int_value()
10731 && parameters->options().warn_mismatch())
10732 gold_error(_("fp16 format mismatch between %s and output"),
10733 name);
10734 }
10735 if (in_attr[i].int_value() != 0)
10736 out_attr[i].set_int_value(in_attr[i].int_value());
10737 break;
10738
10739 case elfcpp::Tag_DIV_use:
10740 // This tag is set to zero if we can use UDIV and SDIV in Thumb
10741 // mode on a v7-M or v7-R CPU; to one if we can not use UDIV or
10742 // SDIV at all; and to two if we can use UDIV or SDIV on a v7-A
10743 // CPU. We will merge as follows: If the input attribute's value
10744 // is one then the output attribute's value remains unchanged. If
10745 // the input attribute's value is zero or two then if the output
10746 // attribute's value is one the output value is set to the input
10747 // value, otherwise the output value must be the same as the
10748 // inputs. */
10749 if (in_attr[i].int_value() != 1 && out_attr[i].int_value() != 1)
10750 {
10751 if (in_attr[i].int_value() != out_attr[i].int_value())
10752 {
10753 gold_error(_("DIV usage mismatch between %s and output"),
10754 name);
10755 }
10756 }
10757
10758 if (in_attr[i].int_value() != 1)
10759 out_attr[i].set_int_value(in_attr[i].int_value());
10760
10761 break;
10762
10763 case elfcpp::Tag_MPextension_use_legacy:
10764 // We don't output objects with Tag_MPextension_use_legacy - we
10765 // move the value to Tag_MPextension_use.
10766 if (in_attr[i].int_value() != 0
10767 && in_attr[elfcpp::Tag_MPextension_use].int_value() != 0)
10768 {
10769 if (in_attr[elfcpp::Tag_MPextension_use].int_value()
10770 != in_attr[i].int_value())
10771 {
10772 gold_error(_("%s has has both the current and legacy "
10773 "Tag_MPextension_use attributes"),
10774 name);
10775 }
10776 }
10777
10778 if (in_attr[i].int_value()
10779 > out_attr[elfcpp::Tag_MPextension_use].int_value())
10780 out_attr[elfcpp::Tag_MPextension_use] = in_attr[i];
10781
10782 break;
10783
10784 case elfcpp::Tag_nodefaults:
10785 // This tag is set if it exists, but the value is unused (and is
10786 // typically zero). We don't actually need to do anything here -
10787 // the merge happens automatically when the type flags are merged
10788 // below.
10789 break;
10790 case elfcpp::Tag_also_compatible_with:
10791 // Already done in Tag_CPU_arch.
10792 break;
10793 case elfcpp::Tag_conformance:
10794 // Keep the attribute if it matches. Throw it away otherwise.
10795 // No attribute means no claim to conform.
10796 if (in_attr[i].string_value() != out_attr[i].string_value())
10797 out_attr[i].set_string_value("");
10798 break;
10799
10800 default:
10801 {
10802 const char* err_object = NULL;
10803
10804 // The "known_obj_attributes" table does contain some undefined
10805 // attributes. Ensure that there are unused.
10806 if (out_attr[i].int_value() != 0
10807 || out_attr[i].string_value() != "")
10808 err_object = "output";
10809 else if (in_attr[i].int_value() != 0
10810 || in_attr[i].string_value() != "")
10811 err_object = name;
10812
10813 if (err_object != NULL
10814 && parameters->options().warn_mismatch())
10815 {
10816 // Attribute numbers >=64 (mod 128) can be safely ignored.
10817 if ((i & 127) < 64)
10818 gold_error(_("%s: unknown mandatory EABI object attribute "
10819 "%d"),
10820 err_object, i);
10821 else
10822 gold_warning(_("%s: unknown EABI object attribute %d"),
10823 err_object, i);
10824 }
10825
10826 // Only pass on attributes that match in both inputs.
10827 if (!in_attr[i].matches(out_attr[i]))
10828 {
10829 out_attr[i].set_int_value(0);
10830 out_attr[i].set_string_value("");
10831 }
10832 }
10833 }
10834
10835 // If out_attr was copied from in_attr then it won't have a type yet.
10836 if (in_attr[i].type() && !out_attr[i].type())
10837 out_attr[i].set_type(in_attr[i].type());
10838 }
10839
10840 // Merge Tag_compatibility attributes and any common GNU ones.
10841 this->attributes_section_data_->merge(name, pasd);
10842
10843 // Check for any attributes not known on ARM.
10844 typedef Vendor_object_attributes::Other_attributes Other_attributes;
10845 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
10846 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
10847 Other_attributes* out_other_attributes =
10848 this->attributes_section_data_->other_attributes(vendor);
10849 Other_attributes::iterator out_iter = out_other_attributes->begin();
10850
10851 while (in_iter != in_other_attributes->end()
10852 || out_iter != out_other_attributes->end())
10853 {
10854 const char* err_object = NULL;
10855 int err_tag = 0;
10856
10857 // The tags for each list are in numerical order.
10858 // If the tags are equal, then merge.
10859 if (out_iter != out_other_attributes->end()
10860 && (in_iter == in_other_attributes->end()
10861 || in_iter->first > out_iter->first))
10862 {
10863 // This attribute only exists in output. We can't merge, and we
10864 // don't know what the tag means, so delete it.
10865 err_object = "output";
10866 err_tag = out_iter->first;
10867 int saved_tag = out_iter->first;
10868 delete out_iter->second;
10869 out_other_attributes->erase(out_iter);
10870 out_iter = out_other_attributes->upper_bound(saved_tag);
10871 }
10872 else if (in_iter != in_other_attributes->end()
10873 && (out_iter != out_other_attributes->end()
10874 || in_iter->first < out_iter->first))
10875 {
10876 // This attribute only exists in input. We can't merge, and we
10877 // don't know what the tag means, so ignore it.
10878 err_object = name;
10879 err_tag = in_iter->first;
10880 ++in_iter;
10881 }
10882 else // The tags are equal.
10883 {
10884 // As present, all attributes in the list are unknown, and
10885 // therefore can't be merged meaningfully.
10886 err_object = "output";
10887 err_tag = out_iter->first;
10888
10889 // Only pass on attributes that match in both inputs.
10890 if (!in_iter->second->matches(*(out_iter->second)))
10891 {
10892 // No match. Delete the attribute.
10893 int saved_tag = out_iter->first;
10894 delete out_iter->second;
10895 out_other_attributes->erase(out_iter);
10896 out_iter = out_other_attributes->upper_bound(saved_tag);
10897 }
10898 else
10899 {
10900 // Matched. Keep the attribute and move to the next.
10901 ++out_iter;
10902 ++in_iter;
10903 }
10904 }
10905
10906 if (err_object && parameters->options().warn_mismatch())
10907 {
10908 // Attribute numbers >=64 (mod 128) can be safely ignored. */
10909 if ((err_tag & 127) < 64)
10910 {
10911 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
10912 err_object, err_tag);
10913 }
10914 else
10915 {
10916 gold_warning(_("%s: unknown EABI object attribute %d"),
10917 err_object, err_tag);
10918 }
10919 }
10920 }
10921 }
10922
10923 // Stub-generation methods for Target_arm.
10924
10925 // Make a new Arm_input_section object.
10926
10927 template<bool big_endian>
10928 Arm_input_section<big_endian>*
10929 Target_arm<big_endian>::new_arm_input_section(
10930 Relobj* relobj,
10931 unsigned int shndx)
10932 {
10933 Section_id sid(relobj, shndx);
10934
10935 Arm_input_section<big_endian>* arm_input_section =
10936 new Arm_input_section<big_endian>(relobj, shndx);
10937 arm_input_section->init();
10938
10939 // Register new Arm_input_section in map for look-up.
10940 std::pair<typename Arm_input_section_map::iterator, bool> ins =
10941 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
10942
10943 // Make sure that it we have not created another Arm_input_section
10944 // for this input section already.
10945 gold_assert(ins.second);
10946
10947 return arm_input_section;
10948 }
10949
10950 // Find the Arm_input_section object corresponding to the SHNDX-th input
10951 // section of RELOBJ.
10952
10953 template<bool big_endian>
10954 Arm_input_section<big_endian>*
10955 Target_arm<big_endian>::find_arm_input_section(
10956 Relobj* relobj,
10957 unsigned int shndx) const
10958 {
10959 Section_id sid(relobj, shndx);
10960 typename Arm_input_section_map::const_iterator p =
10961 this->arm_input_section_map_.find(sid);
10962 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
10963 }
10964
10965 // Make a new stub table.
10966
10967 template<bool big_endian>
10968 Stub_table<big_endian>*
10969 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
10970 {
10971 Stub_table<big_endian>* stub_table =
10972 new Stub_table<big_endian>(owner);
10973 this->stub_tables_.push_back(stub_table);
10974
10975 stub_table->set_address(owner->address() + owner->data_size());
10976 stub_table->set_file_offset(owner->offset() + owner->data_size());
10977 stub_table->finalize_data_size();
10978
10979 return stub_table;
10980 }
10981
10982 // Scan a relocation for stub generation.
10983
10984 template<bool big_endian>
10985 void
10986 Target_arm<big_endian>::scan_reloc_for_stub(
10987 const Relocate_info<32, big_endian>* relinfo,
10988 unsigned int r_type,
10989 const Sized_symbol<32>* gsym,
10990 unsigned int r_sym,
10991 const Symbol_value<32>* psymval,
10992 elfcpp::Elf_types<32>::Elf_Swxword addend,
10993 Arm_address address)
10994 {
10995 const Arm_relobj<big_endian>* arm_relobj =
10996 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10997
10998 bool target_is_thumb;
10999 Symbol_value<32> symval;
11000 if (gsym != NULL)
11001 {
11002 // This is a global symbol. Determine if we use PLT and if the
11003 // final target is THUMB.
11004 if (gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
11005 {
11006 // This uses a PLT, change the symbol value.
11007 symval.set_output_value(this->plt_section()->address()
11008 + gsym->plt_offset());
11009 psymval = &symval;
11010 target_is_thumb = false;
11011 }
11012 else if (gsym->is_undefined())
11013 // There is no need to generate a stub symbol is undefined.
11014 return;
11015 else
11016 {
11017 target_is_thumb =
11018 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
11019 || (gsym->type() == elfcpp::STT_FUNC
11020 && !gsym->is_undefined()
11021 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
11022 }
11023 }
11024 else
11025 {
11026 // This is a local symbol. Determine if the final target is THUMB.
11027 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
11028 }
11029
11030 // Strip LSB if this points to a THUMB target.
11031 const Arm_reloc_property* reloc_property =
11032 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
11033 gold_assert(reloc_property != NULL);
11034 if (target_is_thumb
11035 && reloc_property->uses_thumb_bit()
11036 && ((psymval->value(arm_relobj, 0) & 1) != 0))
11037 {
11038 Arm_address stripped_value =
11039 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
11040 symval.set_output_value(stripped_value);
11041 psymval = &symval;
11042 }
11043
11044 // Get the symbol value.
11045 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
11046
11047 // Owing to pipelining, the PC relative branches below actually skip
11048 // two instructions when the branch offset is 0.
11049 Arm_address destination;
11050 switch (r_type)
11051 {
11052 case elfcpp::R_ARM_CALL:
11053 case elfcpp::R_ARM_JUMP24:
11054 case elfcpp::R_ARM_PLT32:
11055 // ARM branches.
11056 destination = value + addend + 8;
11057 break;
11058 case elfcpp::R_ARM_THM_CALL:
11059 case elfcpp::R_ARM_THM_XPC22:
11060 case elfcpp::R_ARM_THM_JUMP24:
11061 case elfcpp::R_ARM_THM_JUMP19:
11062 // THUMB branches.
11063 destination = value + addend + 4;
11064 break;
11065 default:
11066 gold_unreachable();
11067 }
11068
11069 Reloc_stub* stub = NULL;
11070 Stub_type stub_type =
11071 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
11072 target_is_thumb);
11073 if (stub_type != arm_stub_none)
11074 {
11075 // Try looking up an existing stub from a stub table.
11076 Stub_table<big_endian>* stub_table =
11077 arm_relobj->stub_table(relinfo->data_shndx);
11078 gold_assert(stub_table != NULL);
11079
11080 // Locate stub by destination.
11081 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
11082
11083 // Create a stub if there is not one already
11084 stub = stub_table->find_reloc_stub(stub_key);
11085 if (stub == NULL)
11086 {
11087 // create a new stub and add it to stub table.
11088 stub = this->stub_factory().make_reloc_stub(stub_type);
11089 stub_table->add_reloc_stub(stub, stub_key);
11090 }
11091
11092 // Record the destination address.
11093 stub->set_destination_address(destination
11094 | (target_is_thumb ? 1 : 0));
11095 }
11096
11097 // For Cortex-A8, we need to record a relocation at 4K page boundary.
11098 if (this->fix_cortex_a8_
11099 && (r_type == elfcpp::R_ARM_THM_JUMP24
11100 || r_type == elfcpp::R_ARM_THM_JUMP19
11101 || r_type == elfcpp::R_ARM_THM_CALL
11102 || r_type == elfcpp::R_ARM_THM_XPC22)
11103 && (address & 0xfffU) == 0xffeU)
11104 {
11105 // Found a candidate. Note we haven't checked the destination is
11106 // within 4K here: if we do so (and don't create a record) we can't
11107 // tell that a branch should have been relocated when scanning later.
11108 this->cortex_a8_relocs_info_[address] =
11109 new Cortex_a8_reloc(stub, r_type,
11110 destination | (target_is_thumb ? 1 : 0));
11111 }
11112 }
11113
11114 // This function scans a relocation sections for stub generation.
11115 // The template parameter Relocate must be a class type which provides
11116 // a single function, relocate(), which implements the machine
11117 // specific part of a relocation.
11118
11119 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
11120 // SHT_REL or SHT_RELA.
11121
11122 // PRELOCS points to the relocation data. RELOC_COUNT is the number
11123 // of relocs. OUTPUT_SECTION is the output section.
11124 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
11125 // mapped to output offsets.
11126
11127 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
11128 // VIEW_SIZE is the size. These refer to the input section, unless
11129 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
11130 // the output section.
11131
11132 template<bool big_endian>
11133 template<int sh_type>
11134 void inline
11135 Target_arm<big_endian>::scan_reloc_section_for_stubs(
11136 const Relocate_info<32, big_endian>* relinfo,
11137 const unsigned char* prelocs,
11138 size_t reloc_count,
11139 Output_section* output_section,
11140 bool needs_special_offset_handling,
11141 const unsigned char* view,
11142 elfcpp::Elf_types<32>::Elf_Addr view_address,
11143 section_size_type)
11144 {
11145 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
11146 const int reloc_size =
11147 Reloc_types<sh_type, 32, big_endian>::reloc_size;
11148
11149 Arm_relobj<big_endian>* arm_object =
11150 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
11151 unsigned int local_count = arm_object->local_symbol_count();
11152
11153 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
11154
11155 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
11156 {
11157 Reltype reloc(prelocs);
11158
11159 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
11160 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
11161 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
11162
11163 r_type = this->get_real_reloc_type(r_type);
11164
11165 // Only a few relocation types need stubs.
11166 if ((r_type != elfcpp::R_ARM_CALL)
11167 && (r_type != elfcpp::R_ARM_JUMP24)
11168 && (r_type != elfcpp::R_ARM_PLT32)
11169 && (r_type != elfcpp::R_ARM_THM_CALL)
11170 && (r_type != elfcpp::R_ARM_THM_XPC22)
11171 && (r_type != elfcpp::R_ARM_THM_JUMP24)
11172 && (r_type != elfcpp::R_ARM_THM_JUMP19)
11173 && (r_type != elfcpp::R_ARM_V4BX))
11174 continue;
11175
11176 section_offset_type offset =
11177 convert_to_section_size_type(reloc.get_r_offset());
11178
11179 if (needs_special_offset_handling)
11180 {
11181 offset = output_section->output_offset(relinfo->object,
11182 relinfo->data_shndx,
11183 offset);
11184 if (offset == -1)
11185 continue;
11186 }
11187
11188 // Create a v4bx stub if --fix-v4bx-interworking is used.
11189 if (r_type == elfcpp::R_ARM_V4BX)
11190 {
11191 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
11192 {
11193 // Get the BX instruction.
11194 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
11195 const Valtype* wv =
11196 reinterpret_cast<const Valtype*>(view + offset);
11197 elfcpp::Elf_types<32>::Elf_Swxword insn =
11198 elfcpp::Swap<32, big_endian>::readval(wv);
11199 const uint32_t reg = (insn & 0xf);
11200
11201 if (reg < 0xf)
11202 {
11203 // Try looking up an existing stub from a stub table.
11204 Stub_table<big_endian>* stub_table =
11205 arm_object->stub_table(relinfo->data_shndx);
11206 gold_assert(stub_table != NULL);
11207
11208 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
11209 {
11210 // create a new stub and add it to stub table.
11211 Arm_v4bx_stub* stub =
11212 this->stub_factory().make_arm_v4bx_stub(reg);
11213 gold_assert(stub != NULL);
11214 stub_table->add_arm_v4bx_stub(stub);
11215 }
11216 }
11217 }
11218 continue;
11219 }
11220
11221 // Get the addend.
11222 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
11223 elfcpp::Elf_types<32>::Elf_Swxword addend =
11224 stub_addend_reader(r_type, view + offset, reloc);
11225
11226 const Sized_symbol<32>* sym;
11227
11228 Symbol_value<32> symval;
11229 const Symbol_value<32> *psymval;
11230 bool is_defined_in_discarded_section;
11231 unsigned int shndx;
11232 if (r_sym < local_count)
11233 {
11234 sym = NULL;
11235 psymval = arm_object->local_symbol(r_sym);
11236
11237 // If the local symbol belongs to a section we are discarding,
11238 // and that section is a debug section, try to find the
11239 // corresponding kept section and map this symbol to its
11240 // counterpart in the kept section. The symbol must not
11241 // correspond to a section we are folding.
11242 bool is_ordinary;
11243 shndx = psymval->input_shndx(&is_ordinary);
11244 is_defined_in_discarded_section =
11245 (is_ordinary
11246 && shndx != elfcpp::SHN_UNDEF
11247 && !arm_object->is_section_included(shndx)
11248 && !relinfo->symtab->is_section_folded(arm_object, shndx));
11249
11250 // We need to compute the would-be final value of this local
11251 // symbol.
11252 if (!is_defined_in_discarded_section)
11253 {
11254 typedef Sized_relobj_file<32, big_endian> ObjType;
11255 typename ObjType::Compute_final_local_value_status status =
11256 arm_object->compute_final_local_value(r_sym, psymval, &symval,
11257 relinfo->symtab);
11258 if (status == ObjType::CFLV_OK)
11259 {
11260 // Currently we cannot handle a branch to a target in
11261 // a merged section. If this is the case, issue an error
11262 // and also free the merge symbol value.
11263 if (!symval.has_output_value())
11264 {
11265 const std::string& section_name =
11266 arm_object->section_name(shndx);
11267 arm_object->error(_("cannot handle branch to local %u "
11268 "in a merged section %s"),
11269 r_sym, section_name.c_str());
11270 }
11271 psymval = &symval;
11272 }
11273 else
11274 {
11275 // We cannot determine the final value.
11276 continue;
11277 }
11278 }
11279 }
11280 else
11281 {
11282 const Symbol* gsym;
11283 gsym = arm_object->global_symbol(r_sym);
11284 gold_assert(gsym != NULL);
11285 if (gsym->is_forwarder())
11286 gsym = relinfo->symtab->resolve_forwards(gsym);
11287
11288 sym = static_cast<const Sized_symbol<32>*>(gsym);
11289 if (sym->has_symtab_index() && sym->symtab_index() != -1U)
11290 symval.set_output_symtab_index(sym->symtab_index());
11291 else
11292 symval.set_no_output_symtab_entry();
11293
11294 // We need to compute the would-be final value of this global
11295 // symbol.
11296 const Symbol_table* symtab = relinfo->symtab;
11297 const Sized_symbol<32>* sized_symbol =
11298 symtab->get_sized_symbol<32>(gsym);
11299 Symbol_table::Compute_final_value_status status;
11300 Arm_address value =
11301 symtab->compute_final_value<32>(sized_symbol, &status);
11302
11303 // Skip this if the symbol has not output section.
11304 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
11305 continue;
11306 symval.set_output_value(value);
11307
11308 if (gsym->type() == elfcpp::STT_TLS)
11309 symval.set_is_tls_symbol();
11310 else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
11311 symval.set_is_ifunc_symbol();
11312 psymval = &symval;
11313
11314 is_defined_in_discarded_section =
11315 (gsym->is_defined_in_discarded_section()
11316 && gsym->is_undefined());
11317 shndx = 0;
11318 }
11319
11320 Symbol_value<32> symval2;
11321 if (is_defined_in_discarded_section)
11322 {
11323 if (comdat_behavior == CB_UNDETERMINED)
11324 {
11325 std::string name = arm_object->section_name(relinfo->data_shndx);
11326 comdat_behavior = get_comdat_behavior(name.c_str());
11327 }
11328 if (comdat_behavior == CB_PRETEND)
11329 {
11330 // FIXME: This case does not work for global symbols.
11331 // We have no place to store the original section index.
11332 // Fortunately this does not matter for comdat sections,
11333 // only for sections explicitly discarded by a linker
11334 // script.
11335 bool found;
11336 typename elfcpp::Elf_types<32>::Elf_Addr value =
11337 arm_object->map_to_kept_section(shndx, &found);
11338 if (found)
11339 symval2.set_output_value(value + psymval->input_value());
11340 else
11341 symval2.set_output_value(0);
11342 }
11343 else
11344 {
11345 if (comdat_behavior == CB_WARNING)
11346 gold_warning_at_location(relinfo, i, offset,
11347 _("relocation refers to discarded "
11348 "section"));
11349 symval2.set_output_value(0);
11350 }
11351 symval2.set_no_output_symtab_entry();
11352 psymval = &symval2;
11353 }
11354
11355 // If symbol is a section symbol, we don't know the actual type of
11356 // destination. Give up.
11357 if (psymval->is_section_symbol())
11358 continue;
11359
11360 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
11361 addend, view_address + offset);
11362 }
11363 }
11364
11365 // Scan an input section for stub generation.
11366
11367 template<bool big_endian>
11368 void
11369 Target_arm<big_endian>::scan_section_for_stubs(
11370 const Relocate_info<32, big_endian>* relinfo,
11371 unsigned int sh_type,
11372 const unsigned char* prelocs,
11373 size_t reloc_count,
11374 Output_section* output_section,
11375 bool needs_special_offset_handling,
11376 const unsigned char* view,
11377 Arm_address view_address,
11378 section_size_type view_size)
11379 {
11380 if (sh_type == elfcpp::SHT_REL)
11381 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
11382 relinfo,
11383 prelocs,
11384 reloc_count,
11385 output_section,
11386 needs_special_offset_handling,
11387 view,
11388 view_address,
11389 view_size);
11390 else if (sh_type == elfcpp::SHT_RELA)
11391 // We do not support RELA type relocations yet. This is provided for
11392 // completeness.
11393 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
11394 relinfo,
11395 prelocs,
11396 reloc_count,
11397 output_section,
11398 needs_special_offset_handling,
11399 view,
11400 view_address,
11401 view_size);
11402 else
11403 gold_unreachable();
11404 }
11405
11406 // Group input sections for stub generation.
11407 //
11408 // We group input sections in an output section so that the total size,
11409 // including any padding space due to alignment is smaller than GROUP_SIZE
11410 // unless the only input section in group is bigger than GROUP_SIZE already.
11411 // Then an ARM stub table is created to follow the last input section
11412 // in group. For each group an ARM stub table is created an is placed
11413 // after the last group. If STUB_ALWAYS_AFTER_BRANCH is false, we further
11414 // extend the group after the stub table.
11415
11416 template<bool big_endian>
11417 void
11418 Target_arm<big_endian>::group_sections(
11419 Layout* layout,
11420 section_size_type group_size,
11421 bool stubs_always_after_branch,
11422 const Task* task)
11423 {
11424 // Group input sections and insert stub table
11425 Layout::Section_list section_list;
11426 layout->get_allocated_sections(&section_list);
11427 for (Layout::Section_list::const_iterator p = section_list.begin();
11428 p != section_list.end();
11429 ++p)
11430 {
11431 Arm_output_section<big_endian>* output_section =
11432 Arm_output_section<big_endian>::as_arm_output_section(*p);
11433 output_section->group_sections(group_size, stubs_always_after_branch,
11434 this, task);
11435 }
11436 }
11437
11438 // Relaxation hook. This is where we do stub generation.
11439
11440 template<bool big_endian>
11441 bool
11442 Target_arm<big_endian>::do_relax(
11443 int pass,
11444 const Input_objects* input_objects,
11445 Symbol_table* symtab,
11446 Layout* layout,
11447 const Task* task)
11448 {
11449 // No need to generate stubs if this is a relocatable link.
11450 gold_assert(!parameters->options().relocatable());
11451
11452 // If this is the first pass, we need to group input sections into
11453 // stub groups.
11454 bool done_exidx_fixup = false;
11455 typedef typename Stub_table_list::iterator Stub_table_iterator;
11456 if (pass == 1)
11457 {
11458 // Determine the stub group size. The group size is the absolute
11459 // value of the parameter --stub-group-size. If --stub-group-size
11460 // is passed a negative value, we restrict stubs to be always after
11461 // the stubbed branches.
11462 int32_t stub_group_size_param =
11463 parameters->options().stub_group_size();
11464 bool stubs_always_after_branch = stub_group_size_param < 0;
11465 section_size_type stub_group_size = abs(stub_group_size_param);
11466
11467 if (stub_group_size == 1)
11468 {
11469 // Default value.
11470 // Thumb branch range is +-4MB has to be used as the default
11471 // maximum size (a given section can contain both ARM and Thumb
11472 // code, so the worst case has to be taken into account). If we are
11473 // fixing cortex-a8 errata, the branch range has to be even smaller,
11474 // since wide conditional branch has a range of +-1MB only.
11475 //
11476 // This value is 48K less than that, which allows for 4096
11477 // 12-byte stubs. If we exceed that, then we will fail to link.
11478 // The user will have to relink with an explicit group size
11479 // option.
11480 stub_group_size = 4145152;
11481 }
11482
11483 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
11484 // page as the first half of a 32-bit branch straddling two 4K pages.
11485 // This is a crude way of enforcing that. In addition, long conditional
11486 // branches of THUMB-2 have a range of +-1M. If we are fixing cortex-A8
11487 // erratum, limit the group size to (1M - 12k) to avoid unreachable
11488 // cortex-A8 stubs from long conditional branches.
11489 if (this->fix_cortex_a8_)
11490 {
11491 stubs_always_after_branch = true;
11492 const section_size_type cortex_a8_group_size = 1024 * (1024 - 12);
11493 stub_group_size = std::max(stub_group_size, cortex_a8_group_size);
11494 }
11495
11496 group_sections(layout, stub_group_size, stubs_always_after_branch, task);
11497
11498 // Also fix .ARM.exidx section coverage.
11499 Arm_output_section<big_endian>* exidx_output_section = NULL;
11500 for (Layout::Section_list::const_iterator p =
11501 layout->section_list().begin();
11502 p != layout->section_list().end();
11503 ++p)
11504 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
11505 {
11506 if (exidx_output_section == NULL)
11507 exidx_output_section =
11508 Arm_output_section<big_endian>::as_arm_output_section(*p);
11509 else
11510 // We cannot handle this now.
11511 gold_error(_("multiple SHT_ARM_EXIDX sections %s and %s in a "
11512 "non-relocatable link"),
11513 exidx_output_section->name(),
11514 (*p)->name());
11515 }
11516
11517 if (exidx_output_section != NULL)
11518 {
11519 this->fix_exidx_coverage(layout, input_objects, exidx_output_section,
11520 symtab, task);
11521 done_exidx_fixup = true;
11522 }
11523 }
11524 else
11525 {
11526 // If this is not the first pass, addresses and file offsets have
11527 // been reset at this point, set them here.
11528 for (Stub_table_iterator sp = this->stub_tables_.begin();
11529 sp != this->stub_tables_.end();
11530 ++sp)
11531 {
11532 Arm_input_section<big_endian>* owner = (*sp)->owner();
11533 off_t off = align_address(owner->original_size(),
11534 (*sp)->addralign());
11535 (*sp)->set_address_and_file_offset(owner->address() + off,
11536 owner->offset() + off);
11537 }
11538 }
11539
11540 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
11541 // beginning of each relaxation pass, just blow away all the stubs.
11542 // Alternatively, we could selectively remove only the stubs and reloc
11543 // information for code sections that have moved since the last pass.
11544 // That would require more book-keeping.
11545 if (this->fix_cortex_a8_)
11546 {
11547 // Clear all Cortex-A8 reloc information.
11548 for (typename Cortex_a8_relocs_info::const_iterator p =
11549 this->cortex_a8_relocs_info_.begin();
11550 p != this->cortex_a8_relocs_info_.end();
11551 ++p)
11552 delete p->second;
11553 this->cortex_a8_relocs_info_.clear();
11554
11555 // Remove all Cortex-A8 stubs.
11556 for (Stub_table_iterator sp = this->stub_tables_.begin();
11557 sp != this->stub_tables_.end();
11558 ++sp)
11559 (*sp)->remove_all_cortex_a8_stubs();
11560 }
11561
11562 // Scan relocs for relocation stubs
11563 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11564 op != input_objects->relobj_end();
11565 ++op)
11566 {
11567 Arm_relobj<big_endian>* arm_relobj =
11568 Arm_relobj<big_endian>::as_arm_relobj(*op);
11569 // Lock the object so we can read from it. This is only called
11570 // single-threaded from Layout::finalize, so it is OK to lock.
11571 Task_lock_obj<Object> tl(task, arm_relobj);
11572 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
11573 }
11574
11575 // Check all stub tables to see if any of them have their data sizes
11576 // or addresses alignments changed. These are the only things that
11577 // matter.
11578 bool any_stub_table_changed = false;
11579 Unordered_set<const Output_section*> sections_needing_adjustment;
11580 for (Stub_table_iterator sp = this->stub_tables_.begin();
11581 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11582 ++sp)
11583 {
11584 if ((*sp)->update_data_size_and_addralign())
11585 {
11586 // Update data size of stub table owner.
11587 Arm_input_section<big_endian>* owner = (*sp)->owner();
11588 uint64_t address = owner->address();
11589 off_t offset = owner->offset();
11590 owner->reset_address_and_file_offset();
11591 owner->set_address_and_file_offset(address, offset);
11592
11593 sections_needing_adjustment.insert(owner->output_section());
11594 any_stub_table_changed = true;
11595 }
11596 }
11597
11598 // Output_section_data::output_section() returns a const pointer but we
11599 // need to update output sections, so we record all output sections needing
11600 // update above and scan the sections here to find out what sections need
11601 // to be updated.
11602 for (Layout::Section_list::const_iterator p = layout->section_list().begin();
11603 p != layout->section_list().end();
11604 ++p)
11605 {
11606 if (sections_needing_adjustment.find(*p)
11607 != sections_needing_adjustment.end())
11608 (*p)->set_section_offsets_need_adjustment();
11609 }
11610
11611 // Stop relaxation if no EXIDX fix-up and no stub table change.
11612 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
11613
11614 // Finalize the stubs in the last relaxation pass.
11615 if (!continue_relaxation)
11616 {
11617 for (Stub_table_iterator sp = this->stub_tables_.begin();
11618 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11619 ++sp)
11620 (*sp)->finalize_stubs();
11621
11622 // Update output local symbol counts of objects if necessary.
11623 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11624 op != input_objects->relobj_end();
11625 ++op)
11626 {
11627 Arm_relobj<big_endian>* arm_relobj =
11628 Arm_relobj<big_endian>::as_arm_relobj(*op);
11629
11630 // Update output local symbol counts. We need to discard local
11631 // symbols defined in parts of input sections that are discarded by
11632 // relaxation.
11633 if (arm_relobj->output_local_symbol_count_needs_update())
11634 {
11635 // We need to lock the object's file to update it.
11636 Task_lock_obj<Object> tl(task, arm_relobj);
11637 arm_relobj->update_output_local_symbol_count();
11638 }
11639 }
11640 }
11641
11642 return continue_relaxation;
11643 }
11644
11645 // Relocate a stub.
11646
11647 template<bool big_endian>
11648 void
11649 Target_arm<big_endian>::relocate_stub(
11650 Stub* stub,
11651 const Relocate_info<32, big_endian>* relinfo,
11652 Output_section* output_section,
11653 unsigned char* view,
11654 Arm_address address,
11655 section_size_type view_size)
11656 {
11657 Relocate relocate;
11658 const Stub_template* stub_template = stub->stub_template();
11659 for (size_t i = 0; i < stub_template->reloc_count(); i++)
11660 {
11661 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
11662 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
11663
11664 unsigned int r_type = insn->r_type();
11665 section_size_type reloc_offset = stub_template->reloc_offset(i);
11666 section_size_type reloc_size = insn->size();
11667 gold_assert(reloc_offset + reloc_size <= view_size);
11668
11669 // This is the address of the stub destination.
11670 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
11671 Symbol_value<32> symval;
11672 symval.set_output_value(target);
11673
11674 // Synthesize a fake reloc just in case. We don't have a symbol so
11675 // we use 0.
11676 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
11677 memset(reloc_buffer, 0, sizeof(reloc_buffer));
11678 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
11679 reloc_write.put_r_offset(reloc_offset);
11680 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
11681 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
11682
11683 relocate.relocate(relinfo, this, output_section,
11684 this->fake_relnum_for_stubs, rel, r_type,
11685 NULL, &symval, view + reloc_offset,
11686 address + reloc_offset, reloc_size);
11687 }
11688 }
11689
11690 // Determine whether an object attribute tag takes an integer, a
11691 // string or both.
11692
11693 template<bool big_endian>
11694 int
11695 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
11696 {
11697 if (tag == Object_attribute::Tag_compatibility)
11698 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11699 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
11700 else if (tag == elfcpp::Tag_nodefaults)
11701 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11702 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
11703 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
11704 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
11705 else if (tag < 32)
11706 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
11707 else
11708 return ((tag & 1) != 0
11709 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
11710 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
11711 }
11712
11713 // Reorder attributes.
11714 //
11715 // The ABI defines that Tag_conformance should be emitted first, and that
11716 // Tag_nodefaults should be second (if either is defined). This sets those
11717 // two positions, and bumps up the position of all the remaining tags to
11718 // compensate.
11719
11720 template<bool big_endian>
11721 int
11722 Target_arm<big_endian>::do_attributes_order(int num) const
11723 {
11724 // Reorder the known object attributes in output. We want to move
11725 // Tag_conformance to position 4 and Tag_conformance to position 5
11726 // and shift everything between 4 .. Tag_conformance - 1 to make room.
11727 if (num == 4)
11728 return elfcpp::Tag_conformance;
11729 if (num == 5)
11730 return elfcpp::Tag_nodefaults;
11731 if ((num - 2) < elfcpp::Tag_nodefaults)
11732 return num - 2;
11733 if ((num - 1) < elfcpp::Tag_conformance)
11734 return num - 1;
11735 return num;
11736 }
11737
11738 // Scan a span of THUMB code for Cortex-A8 erratum.
11739
11740 template<bool big_endian>
11741 void
11742 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
11743 Arm_relobj<big_endian>* arm_relobj,
11744 unsigned int shndx,
11745 section_size_type span_start,
11746 section_size_type span_end,
11747 const unsigned char* view,
11748 Arm_address address)
11749 {
11750 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
11751 //
11752 // The opcode is BLX.W, BL.W, B.W, Bcc.W
11753 // The branch target is in the same 4KB region as the
11754 // first half of the branch.
11755 // The instruction before the branch is a 32-bit
11756 // length non-branch instruction.
11757 section_size_type i = span_start;
11758 bool last_was_32bit = false;
11759 bool last_was_branch = false;
11760 while (i < span_end)
11761 {
11762 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11763 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
11764 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
11765 bool is_blx = false, is_b = false;
11766 bool is_bl = false, is_bcc = false;
11767
11768 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
11769 if (insn_32bit)
11770 {
11771 // Load the rest of the insn (in manual-friendly order).
11772 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
11773
11774 // Encoding T4: B<c>.W.
11775 is_b = (insn & 0xf800d000U) == 0xf0009000U;
11776 // Encoding T1: BL<c>.W.
11777 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
11778 // Encoding T2: BLX<c>.W.
11779 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
11780 // Encoding T3: B<c>.W (not permitted in IT block).
11781 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
11782 && (insn & 0x07f00000U) != 0x03800000U);
11783 }
11784
11785 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
11786
11787 // If this instruction is a 32-bit THUMB branch that crosses a 4K
11788 // page boundary and it follows 32-bit non-branch instruction,
11789 // we need to work around.
11790 if (is_32bit_branch
11791 && ((address + i) & 0xfffU) == 0xffeU
11792 && last_was_32bit
11793 && !last_was_branch)
11794 {
11795 // Check to see if there is a relocation stub for this branch.
11796 bool force_target_arm = false;
11797 bool force_target_thumb = false;
11798 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
11799 Cortex_a8_relocs_info::const_iterator p =
11800 this->cortex_a8_relocs_info_.find(address + i);
11801
11802 if (p != this->cortex_a8_relocs_info_.end())
11803 {
11804 cortex_a8_reloc = p->second;
11805 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
11806
11807 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11808 && !target_is_thumb)
11809 force_target_arm = true;
11810 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11811 && target_is_thumb)
11812 force_target_thumb = true;
11813 }
11814
11815 off_t offset;
11816 Stub_type stub_type = arm_stub_none;
11817
11818 // Check if we have an offending branch instruction.
11819 uint16_t upper_insn = (insn >> 16) & 0xffffU;
11820 uint16_t lower_insn = insn & 0xffffU;
11821 typedef class Arm_relocate_functions<big_endian> RelocFuncs;
11822
11823 if (cortex_a8_reloc != NULL
11824 && cortex_a8_reloc->reloc_stub() != NULL)
11825 // We've already made a stub for this instruction, e.g.
11826 // it's a long branch or a Thumb->ARM stub. Assume that
11827 // stub will suffice to work around the A8 erratum (see
11828 // setting of always_after_branch above).
11829 ;
11830 else if (is_bcc)
11831 {
11832 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
11833 lower_insn);
11834 stub_type = arm_stub_a8_veneer_b_cond;
11835 }
11836 else if (is_b || is_bl || is_blx)
11837 {
11838 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
11839 lower_insn);
11840 if (is_blx)
11841 offset &= ~3;
11842
11843 stub_type = (is_blx
11844 ? arm_stub_a8_veneer_blx
11845 : (is_bl
11846 ? arm_stub_a8_veneer_bl
11847 : arm_stub_a8_veneer_b));
11848 }
11849
11850 if (stub_type != arm_stub_none)
11851 {
11852 Arm_address pc_for_insn = address + i + 4;
11853
11854 // The original instruction is a BL, but the target is
11855 // an ARM instruction. If we were not making a stub,
11856 // the BL would have been converted to a BLX. Use the
11857 // BLX stub instead in that case.
11858 if (this->may_use_v5t_interworking() && force_target_arm
11859 && stub_type == arm_stub_a8_veneer_bl)
11860 {
11861 stub_type = arm_stub_a8_veneer_blx;
11862 is_blx = true;
11863 is_bl = false;
11864 }
11865 // Conversely, if the original instruction was
11866 // BLX but the target is Thumb mode, use the BL stub.
11867 else if (force_target_thumb
11868 && stub_type == arm_stub_a8_veneer_blx)
11869 {
11870 stub_type = arm_stub_a8_veneer_bl;
11871 is_blx = false;
11872 is_bl = true;
11873 }
11874
11875 if (is_blx)
11876 pc_for_insn &= ~3;
11877
11878 // If we found a relocation, use the proper destination,
11879 // not the offset in the (unrelocated) instruction.
11880 // Note this is always done if we switched the stub type above.
11881 if (cortex_a8_reloc != NULL)
11882 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
11883
11884 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
11885
11886 // Add a new stub if destination address in in the same page.
11887 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
11888 {
11889 Cortex_a8_stub* stub =
11890 this->stub_factory_.make_cortex_a8_stub(stub_type,
11891 arm_relobj, shndx,
11892 address + i,
11893 target, insn);
11894 Stub_table<big_endian>* stub_table =
11895 arm_relobj->stub_table(shndx);
11896 gold_assert(stub_table != NULL);
11897 stub_table->add_cortex_a8_stub(address + i, stub);
11898 }
11899 }
11900 }
11901
11902 i += insn_32bit ? 4 : 2;
11903 last_was_32bit = insn_32bit;
11904 last_was_branch = is_32bit_branch;
11905 }
11906 }
11907
11908 // Apply the Cortex-A8 workaround.
11909
11910 template<bool big_endian>
11911 void
11912 Target_arm<big_endian>::apply_cortex_a8_workaround(
11913 const Cortex_a8_stub* stub,
11914 Arm_address stub_address,
11915 unsigned char* insn_view,
11916 Arm_address insn_address)
11917 {
11918 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11919 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
11920 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
11921 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
11922 off_t branch_offset = stub_address - (insn_address + 4);
11923
11924 typedef class Arm_relocate_functions<big_endian> RelocFuncs;
11925 switch (stub->stub_template()->type())
11926 {
11927 case arm_stub_a8_veneer_b_cond:
11928 // For a conditional branch, we re-write it to be an unconditional
11929 // branch to the stub. We use the THUMB-2 encoding here.
11930 upper_insn = 0xf000U;
11931 lower_insn = 0xb800U;
11932 // Fall through
11933 case arm_stub_a8_veneer_b:
11934 case arm_stub_a8_veneer_bl:
11935 case arm_stub_a8_veneer_blx:
11936 if ((lower_insn & 0x5000U) == 0x4000U)
11937 // For a BLX instruction, make sure that the relocation is
11938 // rounded up to a word boundary. This follows the semantics of
11939 // the instruction which specifies that bit 1 of the target
11940 // address will come from bit 1 of the base address.
11941 branch_offset = (branch_offset + 2) & ~3;
11942
11943 // Put BRANCH_OFFSET back into the insn.
11944 gold_assert(!Bits<25>::has_overflow32(branch_offset));
11945 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
11946 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
11947 break;
11948
11949 default:
11950 gold_unreachable();
11951 }
11952
11953 // Put the relocated value back in the object file:
11954 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
11955 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
11956 }
11957
11958 // Target selector for ARM. Note this is never instantiated directly.
11959 // It's only used in Target_selector_arm_nacl, below.
11960
11961 template<bool big_endian>
11962 class Target_selector_arm : public Target_selector
11963 {
11964 public:
11965 Target_selector_arm()
11966 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
11967 (big_endian ? "elf32-bigarm" : "elf32-littlearm"),
11968 (big_endian ? "armelfb" : "armelf"))
11969 { }
11970
11971 Target*
11972 do_instantiate_target()
11973 { return new Target_arm<big_endian>(); }
11974 };
11975
11976 // Fix .ARM.exidx section coverage.
11977
11978 template<bool big_endian>
11979 void
11980 Target_arm<big_endian>::fix_exidx_coverage(
11981 Layout* layout,
11982 const Input_objects* input_objects,
11983 Arm_output_section<big_endian>* exidx_section,
11984 Symbol_table* symtab,
11985 const Task* task)
11986 {
11987 // We need to look at all the input sections in output in ascending
11988 // order of of output address. We do that by building a sorted list
11989 // of output sections by addresses. Then we looks at the output sections
11990 // in order. The input sections in an output section are already sorted
11991 // by addresses within the output section.
11992
11993 typedef std::set<Output_section*, output_section_address_less_than>
11994 Sorted_output_section_list;
11995 Sorted_output_section_list sorted_output_sections;
11996
11997 // Find out all the output sections of input sections pointed by
11998 // EXIDX input sections.
11999 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
12000 p != input_objects->relobj_end();
12001 ++p)
12002 {
12003 Arm_relobj<big_endian>* arm_relobj =
12004 Arm_relobj<big_endian>::as_arm_relobj(*p);
12005 std::vector<unsigned int> shndx_list;
12006 arm_relobj->get_exidx_shndx_list(&shndx_list);
12007 for (size_t i = 0; i < shndx_list.size(); ++i)
12008 {
12009 const Arm_exidx_input_section* exidx_input_section =
12010 arm_relobj->exidx_input_section_by_shndx(shndx_list[i]);
12011 gold_assert(exidx_input_section != NULL);
12012 if (!exidx_input_section->has_errors())
12013 {
12014 unsigned int text_shndx = exidx_input_section->link();
12015 Output_section* os = arm_relobj->output_section(text_shndx);
12016 if (os != NULL && (os->flags() & elfcpp::SHF_ALLOC) != 0)
12017 sorted_output_sections.insert(os);
12018 }
12019 }
12020 }
12021
12022 // Go over the output sections in ascending order of output addresses.
12023 typedef typename Arm_output_section<big_endian>::Text_section_list
12024 Text_section_list;
12025 Text_section_list sorted_text_sections;
12026 for (typename Sorted_output_section_list::iterator p =
12027 sorted_output_sections.begin();
12028 p != sorted_output_sections.end();
12029 ++p)
12030 {
12031 Arm_output_section<big_endian>* arm_output_section =
12032 Arm_output_section<big_endian>::as_arm_output_section(*p);
12033 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
12034 }
12035
12036 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab,
12037 merge_exidx_entries(), task);
12038 }
12039
12040 template<bool big_endian>
12041 void
12042 Target_arm<big_endian>::do_define_standard_symbols(
12043 Symbol_table* symtab,
12044 Layout* layout)
12045 {
12046 // Handle the .ARM.exidx section.
12047 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
12048
12049 if (exidx_section != NULL)
12050 {
12051 // Create __exidx_start and __exidx_end symbols.
12052 symtab->define_in_output_data("__exidx_start",
12053 NULL, // version
12054 Symbol_table::PREDEFINED,
12055 exidx_section,
12056 0, // value
12057 0, // symsize
12058 elfcpp::STT_NOTYPE,
12059 elfcpp::STB_GLOBAL,
12060 elfcpp::STV_HIDDEN,
12061 0, // nonvis
12062 false, // offset_is_from_end
12063 true); // only_if_ref
12064
12065 symtab->define_in_output_data("__exidx_end",
12066 NULL, // version
12067 Symbol_table::PREDEFINED,
12068 exidx_section,
12069 0, // value
12070 0, // symsize
12071 elfcpp::STT_NOTYPE,
12072 elfcpp::STB_GLOBAL,
12073 elfcpp::STV_HIDDEN,
12074 0, // nonvis
12075 true, // offset_is_from_end
12076 true); // only_if_ref
12077 }
12078 else
12079 {
12080 // Define __exidx_start and __exidx_end even when .ARM.exidx
12081 // section is missing to match ld's behaviour.
12082 symtab->define_as_constant("__exidx_start", NULL,
12083 Symbol_table::PREDEFINED,
12084 0, 0, elfcpp::STT_OBJECT,
12085 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
12086 true, false);
12087 symtab->define_as_constant("__exidx_end", NULL,
12088 Symbol_table::PREDEFINED,
12089 0, 0, elfcpp::STT_OBJECT,
12090 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
12091 true, false);
12092 }
12093 }
12094
12095 // NaCl variant. It uses different PLT contents.
12096
12097 template<bool big_endian>
12098 class Output_data_plt_arm_nacl;
12099
12100 template<bool big_endian>
12101 class Target_arm_nacl : public Target_arm<big_endian>
12102 {
12103 public:
12104 Target_arm_nacl()
12105 : Target_arm<big_endian>(&arm_nacl_info)
12106 { }
12107
12108 protected:
12109 virtual Output_data_plt_arm<big_endian>*
12110 do_make_data_plt(Layout* layout, Output_data_space* got_plt)
12111 { return new Output_data_plt_arm_nacl<big_endian>(layout, got_plt); }
12112
12113 private:
12114 static const Target::Target_info arm_nacl_info;
12115 };
12116
12117 template<bool big_endian>
12118 const Target::Target_info Target_arm_nacl<big_endian>::arm_nacl_info =
12119 {
12120 32, // size
12121 big_endian, // is_big_endian
12122 elfcpp::EM_ARM, // machine_code
12123 false, // has_make_symbol
12124 false, // has_resolve
12125 false, // has_code_fill
12126 true, // is_default_stack_executable
12127 false, // can_icf_inline_merge_sections
12128 '\0', // wrap_char
12129 "/lib/ld-nacl-arm.so.1", // dynamic_linker
12130 0x20000, // default_text_segment_address
12131 0x10000, // abi_pagesize (overridable by -z max-page-size)
12132 0x10000, // common_pagesize (overridable by -z common-page-size)
12133 true, // isolate_execinstr
12134 0x10000000, // rosegment_gap
12135 elfcpp::SHN_UNDEF, // small_common_shndx
12136 elfcpp::SHN_UNDEF, // large_common_shndx
12137 0, // small_common_section_flags
12138 0, // large_common_section_flags
12139 ".ARM.attributes", // attributes_section
12140 "aeabi" // attributes_vendor
12141 };
12142
12143 template<bool big_endian>
12144 class Output_data_plt_arm_nacl : public Output_data_plt_arm<big_endian>
12145 {
12146 public:
12147 Output_data_plt_arm_nacl(Layout* layout, Output_data_space* got_plt)
12148 : Output_data_plt_arm<big_endian>(layout, 16, got_plt)
12149 { }
12150
12151 protected:
12152 // Return the offset of the first non-reserved PLT entry.
12153 virtual unsigned int
12154 do_first_plt_entry_offset() const
12155 { return sizeof(first_plt_entry); }
12156
12157 // Return the size of a PLT entry.
12158 virtual unsigned int
12159 do_get_plt_entry_size() const
12160 { return sizeof(plt_entry); }
12161
12162 virtual void
12163 do_fill_first_plt_entry(unsigned char* pov,
12164 Arm_address got_address,
12165 Arm_address plt_address);
12166
12167 virtual void
12168 do_fill_plt_entry(unsigned char* pov,
12169 Arm_address got_address,
12170 Arm_address plt_address,
12171 unsigned int got_offset,
12172 unsigned int plt_offset);
12173
12174 private:
12175 inline uint32_t arm_movw_immediate(uint32_t value)
12176 {
12177 return (value & 0x00000fff) | ((value & 0x0000f000) << 4);
12178 }
12179
12180 inline uint32_t arm_movt_immediate(uint32_t value)
12181 {
12182 return ((value & 0x0fff0000) >> 16) | ((value & 0xf0000000) >> 12);
12183 }
12184
12185 // Template for the first PLT entry.
12186 static const uint32_t first_plt_entry[16];
12187
12188 // Template for subsequent PLT entries.
12189 static const uint32_t plt_entry[4];
12190 };
12191
12192 // The first entry in the PLT.
12193 template<bool big_endian>
12194 const uint32_t Output_data_plt_arm_nacl<big_endian>::first_plt_entry[16] =
12195 {
12196 // First bundle:
12197 0xe300c000, // movw ip, #:lower16:&GOT[2]-.+8
12198 0xe340c000, // movt ip, #:upper16:&GOT[2]-.+8
12199 0xe08cc00f, // add ip, ip, pc
12200 0xe52dc008, // str ip, [sp, #-8]!
12201 // Second bundle:
12202 0xe7dfcf1f, // bfc ip, #30, #2
12203 0xe59cc000, // ldr ip, [ip]
12204 0xe3ccc13f, // bic ip, ip, #0xc000000f
12205 0xe12fff1c, // bx ip
12206 // Third bundle:
12207 0xe320f000, // nop
12208 0xe320f000, // nop
12209 0xe320f000, // nop
12210 // .Lplt_tail:
12211 0xe50dc004, // str ip, [sp, #-4]
12212 // Fourth bundle:
12213 0xe7dfcf1f, // bfc ip, #30, #2
12214 0xe59cc000, // ldr ip, [ip]
12215 0xe3ccc13f, // bic ip, ip, #0xc000000f
12216 0xe12fff1c, // bx ip
12217 };
12218
12219 template<bool big_endian>
12220 void
12221 Output_data_plt_arm_nacl<big_endian>::do_fill_first_plt_entry(
12222 unsigned char* pov,
12223 Arm_address got_address,
12224 Arm_address plt_address)
12225 {
12226 // Write first PLT entry. All but first two words are constants.
12227 const size_t num_first_plt_words = (sizeof(first_plt_entry)
12228 / sizeof(first_plt_entry[0]));
12229
12230 int32_t got_displacement = got_address + 8 - (plt_address + 16);
12231
12232 elfcpp::Swap<32, big_endian>::writeval
12233 (pov + 0, first_plt_entry[0] | arm_movw_immediate (got_displacement));
12234 elfcpp::Swap<32, big_endian>::writeval
12235 (pov + 4, first_plt_entry[1] | arm_movt_immediate (got_displacement));
12236
12237 for (size_t i = 2; i < num_first_plt_words; ++i)
12238 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
12239 }
12240
12241 // Subsequent entries in the PLT.
12242
12243 template<bool big_endian>
12244 const uint32_t Output_data_plt_arm_nacl<big_endian>::plt_entry[4] =
12245 {
12246 0xe300c000, // movw ip, #:lower16:&GOT[n]-.+8
12247 0xe340c000, // movt ip, #:upper16:&GOT[n]-.+8
12248 0xe08cc00f, // add ip, ip, pc
12249 0xea000000, // b .Lplt_tail
12250 };
12251
12252 template<bool big_endian>
12253 void
12254 Output_data_plt_arm_nacl<big_endian>::do_fill_plt_entry(
12255 unsigned char* pov,
12256 Arm_address got_address,
12257 Arm_address plt_address,
12258 unsigned int got_offset,
12259 unsigned int plt_offset)
12260 {
12261 // Calculate the displacement between the PLT slot and the
12262 // common tail that's part of the special initial PLT slot.
12263 int32_t tail_displacement = (plt_address + (11 * sizeof(uint32_t))
12264 - (plt_address + plt_offset
12265 + sizeof(plt_entry) + sizeof(uint32_t)));
12266 gold_assert((tail_displacement & 3) == 0);
12267 tail_displacement >>= 2;
12268
12269 gold_assert ((tail_displacement & 0xff000000) == 0
12270 || (-tail_displacement & 0xff000000) == 0);
12271
12272 // Calculate the displacement between the PLT slot and the entry
12273 // in the GOT. The offset accounts for the value produced by
12274 // adding to pc in the penultimate instruction of the PLT stub.
12275 const int32_t got_displacement = (got_address + got_offset
12276 - (plt_address + sizeof(plt_entry)));
12277
12278 elfcpp::Swap<32, big_endian>::writeval
12279 (pov + 0, plt_entry[0] | arm_movw_immediate (got_displacement));
12280 elfcpp::Swap<32, big_endian>::writeval
12281 (pov + 4, plt_entry[1] | arm_movt_immediate (got_displacement));
12282 elfcpp::Swap<32, big_endian>::writeval
12283 (pov + 8, plt_entry[2]);
12284 elfcpp::Swap<32, big_endian>::writeval
12285 (pov + 12, plt_entry[3] | (tail_displacement & 0x00ffffff));
12286 }
12287
12288 // Target selectors.
12289
12290 template<bool big_endian>
12291 class Target_selector_arm_nacl
12292 : public Target_selector_nacl<Target_selector_arm<big_endian>,
12293 Target_arm_nacl<big_endian> >
12294 {
12295 public:
12296 Target_selector_arm_nacl()
12297 : Target_selector_nacl<Target_selector_arm<big_endian>,
12298 Target_arm_nacl<big_endian> >(
12299 "arm",
12300 big_endian ? "elf32-bigarm-nacl" : "elf32-littlearm-nacl",
12301 big_endian ? "armelfb_nacl" : "armelf_nacl")
12302 { }
12303 };
12304
12305 Target_selector_arm_nacl<false> target_selector_arm;
12306 Target_selector_arm_nacl<true> target_selector_armbe;
12307
12308 } // End anonymous namespace.
This page took 0.282979 seconds and 5 git commands to generate.