2017-06-15 Eric Christopher <echristo@gmail.com>
[external/binutils.git] / gold / aarch64.cc
1 // aarch64.cc -- aarch64 target support for gold.
2
3 // Copyright (C) 2014-2017 Free Software Foundation, Inc.
4 // Written by Jing Yu <jingyu@google.com> and Han Shen <shenhan@google.com>.
5
6 // This file is part of gold.
7
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
12
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 // GNU General Public License for more details.
17
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
22
23 #include "gold.h"
24
25 #include <cstring>
26 #include <map>
27 #include <set>
28
29 #include "elfcpp.h"
30 #include "dwarf.h"
31 #include "parameters.h"
32 #include "reloc.h"
33 #include "aarch64.h"
34 #include "object.h"
35 #include "symtab.h"
36 #include "layout.h"
37 #include "output.h"
38 #include "copy-relocs.h"
39 #include "target.h"
40 #include "target-reloc.h"
41 #include "target-select.h"
42 #include "tls.h"
43 #include "freebsd.h"
44 #include "nacl.h"
45 #include "gc.h"
46 #include "icf.h"
47 #include "aarch64-reloc-property.h"
48
49 // The first three .got.plt entries are reserved.
50 const int32_t AARCH64_GOTPLT_RESERVE_COUNT = 3;
51
52
53 namespace
54 {
55
56 using namespace gold;
57
58 template<int size, bool big_endian>
59 class Output_data_plt_aarch64;
60
61 template<int size, bool big_endian>
62 class Output_data_plt_aarch64_standard;
63
64 template<int size, bool big_endian>
65 class Target_aarch64;
66
67 template<int size, bool big_endian>
68 class AArch64_relocate_functions;
69
70 // Utility class dealing with insns. This is ported from macros in
71 // bfd/elfnn-aarch64.cc, but wrapped inside a class as static members. This
72 // class is used in erratum sequence scanning.
73
74 template<bool big_endian>
75 class AArch64_insn_utilities
76 {
77 public:
78   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
79
80   static const int BYTES_PER_INSN;
81
82   // Zero register encoding - 31.
83   static const unsigned int AARCH64_ZR;
84
85   static unsigned int
86   aarch64_bit(Insntype insn, int pos)
87   { return ((1 << pos)  & insn) >> pos; }
88
89   static unsigned int
90   aarch64_bits(Insntype insn, int pos, int l)
91   { return (insn >> pos) & ((1 << l) - 1); }
92
93   // Get the encoding field "op31" of 3-source data processing insns. "op31" is
94   // the name defined in armv8 insn manual C3.5.9.
95   static unsigned int
96   aarch64_op31(Insntype insn)
97   { return aarch64_bits(insn, 21, 3); }
98
99   // Get the encoding field "ra" of 3-source data processing insns. "ra" is the
100   // third source register. See armv8 insn manual C3.5.9.
101   static unsigned int
102   aarch64_ra(Insntype insn)
103   { return aarch64_bits(insn, 10, 5); }
104
105   static bool
106   is_adr(const Insntype insn)
107   { return (insn & 0x9F000000) == 0x10000000; }
108
109   static bool
110   is_adrp(const Insntype insn)
111   { return (insn & 0x9F000000) == 0x90000000; }
112
113   static bool
114   is_mrs_tpidr_el0(const Insntype insn)
115   { return (insn & 0xFFFFFFE0) == 0xd53bd040; }
116
117   static unsigned int
118   aarch64_rm(const Insntype insn)
119   { return aarch64_bits(insn, 16, 5); }
120
121   static unsigned int
122   aarch64_rn(const Insntype insn)
123   { return aarch64_bits(insn, 5, 5); }
124
125   static unsigned int
126   aarch64_rd(const Insntype insn)
127   { return aarch64_bits(insn, 0, 5); }
128
129   static unsigned int
130   aarch64_rt(const Insntype insn)
131   { return aarch64_bits(insn, 0, 5); }
132
133   static unsigned int
134   aarch64_rt2(const Insntype insn)
135   { return aarch64_bits(insn, 10, 5); }
136
137   // Encode imm21 into adr. Signed imm21 is in the range of [-1M, 1M).
138   static Insntype
139   aarch64_adr_encode_imm(Insntype adr, int imm21)
140   {
141     gold_assert(is_adr(adr));
142     gold_assert(-(1 << 20) <= imm21 && imm21 < (1 << 20));
143     const int mask19 = (1 << 19) - 1;
144     const int mask2 = 3;
145     adr &= ~((mask19 << 5) | (mask2 << 29));
146     adr |= ((imm21 & mask2) << 29) | (((imm21 >> 2) & mask19) << 5);
147     return adr;
148   }
149
150   // Retrieve encoded adrp 33-bit signed imm value. This value is obtained by
151   // 21-bit signed imm encoded in the insn multiplied by 4k (page size) and
152   // 64-bit sign-extended, resulting in [-4G, 4G) with 12-lsb being 0.
153   static int64_t
154   aarch64_adrp_decode_imm(const Insntype adrp)
155   {
156     const int mask19 = (1 << 19) - 1;
157     const int mask2 = 3;
158     gold_assert(is_adrp(adrp));
159     // 21-bit imm encoded in adrp.
160     uint64_t imm = ((adrp >> 29) & mask2) | (((adrp >> 5) & mask19) << 2);
161     // Retrieve msb of 21-bit-signed imm for sign extension.
162     uint64_t msbt = (imm >> 20) & 1;
163     // Real value is imm multiplied by 4k. Value now has 33-bit information.
164     int64_t value = imm << 12;
165     // Sign extend to 64-bit by repeating msbt 31 (64-33) times and merge it
166     // with value.
167     return ((((uint64_t)(1) << 32) - msbt) << 33) | value;
168   }
169
170   static bool
171   aarch64_b(const Insntype insn)
172   { return (insn & 0xFC000000) == 0x14000000; }
173
174   static bool
175   aarch64_bl(const Insntype insn)
176   { return (insn & 0xFC000000) == 0x94000000; }
177
178   static bool
179   aarch64_blr(const Insntype insn)
180   { return (insn & 0xFFFFFC1F) == 0xD63F0000; }
181
182   static bool
183   aarch64_br(const Insntype insn)
184   { return (insn & 0xFFFFFC1F) == 0xD61F0000; }
185
186   // All ld/st ops.  See C4-182 of the ARM ARM.  The encoding space for
187   // LD_PCREL, LDST_RO, LDST_UI and LDST_UIMM cover prefetch ops.
188   static bool
189   aarch64_ld(Insntype insn) { return aarch64_bit(insn, 22) == 1; }
190
191   static bool
192   aarch64_ldst(Insntype insn)
193   { return (insn & 0x0a000000) == 0x08000000; }
194
195   static bool
196   aarch64_ldst_ex(Insntype insn)
197   { return (insn & 0x3f000000) == 0x08000000; }
198
199   static bool
200   aarch64_ldst_pcrel(Insntype insn)
201   { return (insn & 0x3b000000) == 0x18000000; }
202
203   static bool
204   aarch64_ldst_nap(Insntype insn)
205   { return (insn & 0x3b800000) == 0x28000000; }
206
207   static bool
208   aarch64_ldstp_pi(Insntype insn)
209   { return (insn & 0x3b800000) == 0x28800000; }
210
211   static bool
212   aarch64_ldstp_o(Insntype insn)
213   { return (insn & 0x3b800000) == 0x29000000; }
214
215   static bool
216   aarch64_ldstp_pre(Insntype insn)
217   { return (insn & 0x3b800000) == 0x29800000; }
218
219   static bool
220   aarch64_ldst_ui(Insntype insn)
221   { return (insn & 0x3b200c00) == 0x38000000; }
222
223   static bool
224   aarch64_ldst_piimm(Insntype insn)
225   { return (insn & 0x3b200c00) == 0x38000400; }
226
227   static bool
228   aarch64_ldst_u(Insntype insn)
229   { return (insn & 0x3b200c00) == 0x38000800; }
230
231   static bool
232   aarch64_ldst_preimm(Insntype insn)
233   { return (insn & 0x3b200c00) == 0x38000c00; }
234
235   static bool
236   aarch64_ldst_ro(Insntype insn)
237   { return (insn & 0x3b200c00) == 0x38200800; }
238
239   static bool
240   aarch64_ldst_uimm(Insntype insn)
241   { return (insn & 0x3b000000) == 0x39000000; }
242
243   static bool
244   aarch64_ldst_simd_m(Insntype insn)
245   { return (insn & 0xbfbf0000) == 0x0c000000; }
246
247   static bool
248   aarch64_ldst_simd_m_pi(Insntype insn)
249   { return (insn & 0xbfa00000) == 0x0c800000; }
250
251   static bool
252   aarch64_ldst_simd_s(Insntype insn)
253   { return (insn & 0xbf9f0000) == 0x0d000000; }
254
255   static bool
256   aarch64_ldst_simd_s_pi(Insntype insn)
257   { return (insn & 0xbf800000) == 0x0d800000; }
258
259   // Classify an INSN if it is indeed a load/store. Return true if INSN is a
260   // LD/ST instruction otherwise return false. For scalar LD/ST instructions
261   // PAIR is FALSE, RT is returned and RT2 is set equal to RT. For LD/ST pair
262   // instructions PAIR is TRUE, RT and RT2 are returned.
263   static bool
264   aarch64_mem_op_p(Insntype insn, unsigned int *rt, unsigned int *rt2,
265                    bool *pair, bool *load)
266   {
267     uint32_t opcode;
268     unsigned int r;
269     uint32_t opc = 0;
270     uint32_t v = 0;
271     uint32_t opc_v = 0;
272
273     /* Bail out quickly if INSN doesn't fall into the the load-store
274        encoding space.  */
275     if (!aarch64_ldst (insn))
276       return false;
277
278     *pair = false;
279     *load = false;
280     if (aarch64_ldst_ex (insn))
281       {
282         *rt = aarch64_rt (insn);
283         *rt2 = *rt;
284         if (aarch64_bit (insn, 21) == 1)
285           {
286             *pair = true;
287             *rt2 = aarch64_rt2 (insn);
288           }
289         *load = aarch64_ld (insn);
290         return true;
291       }
292     else if (aarch64_ldst_nap (insn)
293              || aarch64_ldstp_pi (insn)
294              || aarch64_ldstp_o (insn)
295              || aarch64_ldstp_pre (insn))
296       {
297         *pair = true;
298         *rt = aarch64_rt (insn);
299         *rt2 = aarch64_rt2 (insn);
300         *load = aarch64_ld (insn);
301         return true;
302       }
303     else if (aarch64_ldst_pcrel (insn)
304              || aarch64_ldst_ui (insn)
305              || aarch64_ldst_piimm (insn)
306              || aarch64_ldst_u (insn)
307              || aarch64_ldst_preimm (insn)
308              || aarch64_ldst_ro (insn)
309              || aarch64_ldst_uimm (insn))
310       {
311         *rt = aarch64_rt (insn);
312         *rt2 = *rt;
313         if (aarch64_ldst_pcrel (insn))
314           *load = true;
315         opc = aarch64_bits (insn, 22, 2);
316         v = aarch64_bit (insn, 26);
317         opc_v = opc | (v << 2);
318         *load =  (opc_v == 1 || opc_v == 2 || opc_v == 3
319                   || opc_v == 5 || opc_v == 7);
320         return true;
321       }
322     else if (aarch64_ldst_simd_m (insn)
323              || aarch64_ldst_simd_m_pi (insn))
324       {
325         *rt = aarch64_rt (insn);
326         *load = aarch64_bit (insn, 22);
327         opcode = (insn >> 12) & 0xf;
328         switch (opcode)
329           {
330           case 0:
331           case 2:
332             *rt2 = *rt + 3;
333             break;
334
335           case 4:
336           case 6:
337             *rt2 = *rt + 2;
338             break;
339
340           case 7:
341             *rt2 = *rt;
342             break;
343
344           case 8:
345           case 10:
346             *rt2 = *rt + 1;
347             break;
348
349           default:
350             return false;
351           }
352         return true;
353       }
354     else if (aarch64_ldst_simd_s (insn)
355              || aarch64_ldst_simd_s_pi (insn))
356       {
357         *rt = aarch64_rt (insn);
358         r = (insn >> 21) & 1;
359         *load = aarch64_bit (insn, 22);
360         opcode = (insn >> 13) & 0x7;
361         switch (opcode)
362           {
363           case 0:
364           case 2:
365           case 4:
366             *rt2 = *rt + r;
367             break;
368
369           case 1:
370           case 3:
371           case 5:
372             *rt2 = *rt + (r == 0 ? 2 : 3);
373             break;
374
375           case 6:
376             *rt2 = *rt + r;
377             break;
378
379           case 7:
380             *rt2 = *rt + (r == 0 ? 2 : 3);
381             break;
382
383           default:
384             return false;
385           }
386         return true;
387       }
388     return false;
389   }  // End of "aarch64_mem_op_p".
390
391   // Return true if INSN is mac insn.
392   static bool
393   aarch64_mac(Insntype insn)
394   { return (insn & 0xff000000) == 0x9b000000; }
395
396   // Return true if INSN is multiply-accumulate.
397   // (This is similar to implementaton in elfnn-aarch64.c.)
398   static bool
399   aarch64_mlxl(Insntype insn)
400   {
401     uint32_t op31 = aarch64_op31(insn);
402     if (aarch64_mac(insn)
403         && (op31 == 0 || op31 == 1 || op31 == 5)
404         /* Exclude MUL instructions which are encoded as a multiple-accumulate
405            with RA = XZR.  */
406         && aarch64_ra(insn) != AARCH64_ZR)
407       {
408         return true;
409       }
410     return false;
411   }
412 };  // End of "AArch64_insn_utilities".
413
414
415 // Insn length in byte.
416
417 template<bool big_endian>
418 const int AArch64_insn_utilities<big_endian>::BYTES_PER_INSN = 4;
419
420
421 // Zero register encoding - 31.
422
423 template<bool big_endian>
424 const unsigned int AArch64_insn_utilities<big_endian>::AARCH64_ZR = 0x1f;
425
426
427 // Output_data_got_aarch64 class.
428
429 template<int size, bool big_endian>
430 class Output_data_got_aarch64 : public Output_data_got<size, big_endian>
431 {
432  public:
433   typedef typename elfcpp::Elf_types<size>::Elf_Addr Valtype;
434   Output_data_got_aarch64(Symbol_table* symtab, Layout* layout)
435     : Output_data_got<size, big_endian>(),
436       symbol_table_(symtab), layout_(layout)
437   { }
438
439   // Add a static entry for the GOT entry at OFFSET.  GSYM is a global
440   // symbol and R_TYPE is the code of a dynamic relocation that needs to be
441   // applied in a static link.
442   void
443   add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
444   { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
445
446
447   // Add a static reloc for the GOT entry at OFFSET.  RELOBJ is an object
448   // defining a local symbol with INDEX.  R_TYPE is the code of a dynamic
449   // relocation that needs to be applied in a static link.
450   void
451   add_static_reloc(unsigned int got_offset, unsigned int r_type,
452                    Sized_relobj_file<size, big_endian>* relobj,
453                    unsigned int index)
454   {
455     this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
456                                                 index));
457   }
458
459
460  protected:
461   // Write out the GOT table.
462   void
463   do_write(Output_file* of) {
464     // The first entry in the GOT is the address of the .dynamic section.
465     gold_assert(this->data_size() >= size / 8);
466     Output_section* dynamic = this->layout_->dynamic_section();
467     Valtype dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
468     this->replace_constant(0, dynamic_addr);
469     Output_data_got<size, big_endian>::do_write(of);
470
471     // Handling static relocs
472     if (this->static_relocs_.empty())
473       return;
474
475     typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
476
477     gold_assert(parameters->doing_static_link());
478     const off_t offset = this->offset();
479     const section_size_type oview_size =
480       convert_to_section_size_type(this->data_size());
481     unsigned char* const oview = of->get_output_view(offset, oview_size);
482
483     Output_segment* tls_segment = this->layout_->tls_segment();
484     gold_assert(tls_segment != NULL);
485
486     AArch64_address aligned_tcb_address =
487       align_address(Target_aarch64<size, big_endian>::TCB_SIZE,
488                     tls_segment->maximum_alignment());
489
490     for (size_t i = 0; i < this->static_relocs_.size(); ++i)
491       {
492         Static_reloc& reloc(this->static_relocs_[i]);
493         AArch64_address value;
494
495         if (!reloc.symbol_is_global())
496           {
497             Sized_relobj_file<size, big_endian>* object = reloc.relobj();
498             const Symbol_value<size>* psymval =
499               reloc.relobj()->local_symbol(reloc.index());
500
501             // We are doing static linking.  Issue an error and skip this
502             // relocation if the symbol is undefined or in a discarded_section.
503             bool is_ordinary;
504             unsigned int shndx = psymval->input_shndx(&is_ordinary);
505             if ((shndx == elfcpp::SHN_UNDEF)
506                 || (is_ordinary
507                     && shndx != elfcpp::SHN_UNDEF
508                     && !object->is_section_included(shndx)
509                     && !this->symbol_table_->is_section_folded(object, shndx)))
510               {
511                 gold_error(_("undefined or discarded local symbol %u from "
512                              " object %s in GOT"),
513                            reloc.index(), reloc.relobj()->name().c_str());
514                 continue;
515               }
516             value = psymval->value(object, 0);
517           }
518         else
519           {
520             const Symbol* gsym = reloc.symbol();
521             gold_assert(gsym != NULL);
522             if (gsym->is_forwarder())
523               gsym = this->symbol_table_->resolve_forwards(gsym);
524
525             // We are doing static linking.  Issue an error and skip this
526             // relocation if the symbol is undefined or in a discarded_section
527             // unless it is a weakly_undefined symbol.
528             if ((gsym->is_defined_in_discarded_section()
529                  || gsym->is_undefined())
530                 && !gsym->is_weak_undefined())
531               {
532                 gold_error(_("undefined or discarded symbol %s in GOT"),
533                            gsym->name());
534                 continue;
535               }
536
537             if (!gsym->is_weak_undefined())
538               {
539                 const Sized_symbol<size>* sym =
540                   static_cast<const Sized_symbol<size>*>(gsym);
541                 value = sym->value();
542               }
543             else
544               value = 0;
545           }
546
547         unsigned got_offset = reloc.got_offset();
548         gold_assert(got_offset < oview_size);
549
550         typedef typename elfcpp::Swap<size, big_endian>::Valtype Valtype;
551         Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
552         Valtype x;
553         switch (reloc.r_type())
554           {
555           case elfcpp::R_AARCH64_TLS_DTPREL64:
556             x = value;
557             break;
558           case elfcpp::R_AARCH64_TLS_TPREL64:
559             x = value + aligned_tcb_address;
560             break;
561           default:
562             gold_unreachable();
563           }
564         elfcpp::Swap<size, big_endian>::writeval(wv, x);
565       }
566
567     of->write_output_view(offset, oview_size, oview);
568   }
569
570  private:
571   // Symbol table of the output object.
572   Symbol_table* symbol_table_;
573   // A pointer to the Layout class, so that we can find the .dynamic
574   // section when we write out the GOT section.
575   Layout* layout_;
576
577   // This class represent dynamic relocations that need to be applied by
578   // gold because we are using TLS relocations in a static link.
579   class Static_reloc
580   {
581    public:
582     Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
583       : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
584     { this->u_.global.symbol = gsym; }
585
586     Static_reloc(unsigned int got_offset, unsigned int r_type,
587           Sized_relobj_file<size, big_endian>* relobj, unsigned int index)
588       : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
589     {
590       this->u_.local.relobj = relobj;
591       this->u_.local.index = index;
592     }
593
594     // Return the GOT offset.
595     unsigned int
596     got_offset() const
597     { return this->got_offset_; }
598
599     // Relocation type.
600     unsigned int
601     r_type() const
602     { return this->r_type_; }
603
604     // Whether the symbol is global or not.
605     bool
606     symbol_is_global() const
607     { return this->symbol_is_global_; }
608
609     // For a relocation against a global symbol, the global symbol.
610     Symbol*
611     symbol() const
612     {
613       gold_assert(this->symbol_is_global_);
614       return this->u_.global.symbol;
615     }
616
617     // For a relocation against a local symbol, the defining object.
618     Sized_relobj_file<size, big_endian>*
619     relobj() const
620     {
621       gold_assert(!this->symbol_is_global_);
622       return this->u_.local.relobj;
623     }
624
625     // For a relocation against a local symbol, the local symbol index.
626     unsigned int
627     index() const
628     {
629       gold_assert(!this->symbol_is_global_);
630       return this->u_.local.index;
631     }
632
633    private:
634     // GOT offset of the entry to which this relocation is applied.
635     unsigned int got_offset_;
636     // Type of relocation.
637     unsigned int r_type_;
638     // Whether this relocation is against a global symbol.
639     bool symbol_is_global_;
640     // A global or local symbol.
641     union
642     {
643       struct
644       {
645         // For a global symbol, the symbol itself.
646         Symbol* symbol;
647       } global;
648       struct
649       {
650         // For a local symbol, the object defining the symbol.
651         Sized_relobj_file<size, big_endian>* relobj;
652         // For a local symbol, the symbol index.
653         unsigned int index;
654       } local;
655     } u_;
656   };  // End of inner class Static_reloc
657
658   std::vector<Static_reloc> static_relocs_;
659 };  // End of Output_data_got_aarch64
660
661
662 template<int size, bool big_endian>
663 class AArch64_input_section;
664
665
666 template<int size, bool big_endian>
667 class AArch64_output_section;
668
669
670 template<int size, bool big_endian>
671 class AArch64_relobj;
672
673
674 // Stub type enum constants.
675
676 enum
677 {
678   ST_NONE = 0,
679
680   // Using adrp/add pair, 4 insns (including alignment) without mem access,
681   // the fastest stub. This has a limited jump distance, which is tested by
682   // aarch64_valid_for_adrp_p.
683   ST_ADRP_BRANCH = 1,
684
685   // Using ldr-absolute-address/br-register, 4 insns with 1 mem access,
686   // unlimited in jump distance.
687   ST_LONG_BRANCH_ABS = 2,
688
689   // Using ldr/calculate-pcrel/jump, 8 insns (including alignment) with 1
690   // mem access, slowest one. Only used in position independent executables.
691   ST_LONG_BRANCH_PCREL = 3,
692
693   // Stub for erratum 843419 handling.
694   ST_E_843419 = 4,
695
696   // Stub for erratum 835769 handling.
697   ST_E_835769 = 5,
698
699   // Number of total stub types.
700   ST_NUMBER = 6
701 };
702
703
704 // Struct that wraps insns for a particular stub. All stub templates are
705 // created/initialized as constants by Stub_template_repertoire.
706
707 template<bool big_endian>
708 struct Stub_template
709 {
710   const typename AArch64_insn_utilities<big_endian>::Insntype* insns;
711   const int insn_num;
712 };
713
714
715 // Simple singleton class that creates/initializes/stores all types of stub
716 // templates.
717
718 template<bool big_endian>
719 class Stub_template_repertoire
720 {
721 public:
722   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
723
724   // Single static method to get stub template for a given stub type.
725   static const Stub_template<big_endian>*
726   get_stub_template(int type)
727   {
728     static Stub_template_repertoire<big_endian> singleton;
729     return singleton.stub_templates_[type];
730   }
731
732 private:
733   // Constructor - creates/initializes all stub templates.
734   Stub_template_repertoire();
735   ~Stub_template_repertoire()
736   { }
737
738   // Disallowing copy ctor and copy assignment operator.
739   Stub_template_repertoire(Stub_template_repertoire&);
740   Stub_template_repertoire& operator=(Stub_template_repertoire&);
741
742   // Data that stores all insn templates.
743   const Stub_template<big_endian>* stub_templates_[ST_NUMBER];
744 };  // End of "class Stub_template_repertoire".
745
746
747 // Constructor - creates/initilizes all stub templates.
748
749 template<bool big_endian>
750 Stub_template_repertoire<big_endian>::Stub_template_repertoire()
751 {
752   // Insn array definitions.
753   const static Insntype ST_NONE_INSNS[] = {};
754
755   const static Insntype ST_ADRP_BRANCH_INSNS[] =
756     {
757       0x90000010,       /*      adrp    ip0, X             */
758                         /*        ADR_PREL_PG_HI21(X)      */
759       0x91000210,       /*      add     ip0, ip0, :lo12:X  */
760                         /*        ADD_ABS_LO12_NC(X)       */
761       0xd61f0200,       /*      br      ip0                */
762       0x00000000,       /*      alignment padding          */
763     };
764
765   const static Insntype ST_LONG_BRANCH_ABS_INSNS[] =
766     {
767       0x58000050,       /*      ldr   ip0, 0x8             */
768       0xd61f0200,       /*      br    ip0                  */
769       0x00000000,       /*      address field              */
770       0x00000000,       /*      address fields             */
771     };
772
773   const static Insntype ST_LONG_BRANCH_PCREL_INSNS[] =
774     {
775       0x58000090,       /*      ldr   ip0, 0x10            */
776       0x10000011,       /*      adr   ip1, #0              */
777       0x8b110210,       /*      add   ip0, ip0, ip1        */
778       0xd61f0200,       /*      br    ip0                  */
779       0x00000000,       /*      address field              */
780       0x00000000,       /*      address field              */
781       0x00000000,       /*      alignment padding          */
782       0x00000000,       /*      alignment padding          */
783     };
784
785   const static Insntype ST_E_843419_INSNS[] =
786     {
787       0x00000000,    /* Placeholder for erratum insn. */
788       0x14000000,    /* b <label> */
789     };
790
791   // ST_E_835769 has the same stub template as ST_E_843419
792   // but we reproduce the array here so that the sizeof
793   // expressions in install_insn_template will work.
794   const static Insntype ST_E_835769_INSNS[] =
795     {
796       0x00000000,    /* Placeholder for erratum insn. */
797       0x14000000,    /* b <label> */
798     };
799
800 #define install_insn_template(T) \
801   const static Stub_template<big_endian> template_##T = {  \
802     T##_INSNS, sizeof(T##_INSNS) / sizeof(T##_INSNS[0]) }; \
803   this->stub_templates_[T] = &template_##T
804
805   install_insn_template(ST_NONE);
806   install_insn_template(ST_ADRP_BRANCH);
807   install_insn_template(ST_LONG_BRANCH_ABS);
808   install_insn_template(ST_LONG_BRANCH_PCREL);
809   install_insn_template(ST_E_843419);
810   install_insn_template(ST_E_835769);
811
812 #undef install_insn_template
813 }
814
815
816 // Base class for stubs.
817
818 template<int size, bool big_endian>
819 class Stub_base
820 {
821 public:
822   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
823   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
824
825   static const AArch64_address invalid_address =
826     static_cast<AArch64_address>(-1);
827
828   static const section_offset_type invalid_offset =
829     static_cast<section_offset_type>(-1);
830
831   Stub_base(int type)
832     : destination_address_(invalid_address),
833       offset_(invalid_offset),
834       type_(type)
835   {}
836
837   ~Stub_base()
838   {}
839
840   // Get stub type.
841   int
842   type() const
843   { return this->type_; }
844
845   // Get stub template that provides stub insn information.
846   const Stub_template<big_endian>*
847   stub_template() const
848   {
849     return Stub_template_repertoire<big_endian>::
850       get_stub_template(this->type());
851   }
852
853   // Get destination address.
854   AArch64_address
855   destination_address() const
856   {
857     gold_assert(this->destination_address_ != this->invalid_address);
858     return this->destination_address_;
859   }
860
861   // Set destination address.
862   void
863   set_destination_address(AArch64_address address)
864   {
865     gold_assert(address != this->invalid_address);
866     this->destination_address_ = address;
867   }
868
869   // Reset the destination address.
870   void
871   reset_destination_address()
872   { this->destination_address_ = this->invalid_address; }
873
874   // Get offset of code stub. For Reloc_stub, it is the offset from the
875   // beginning of its containing stub table; for Erratum_stub, it is the offset
876   // from the end of reloc_stubs.
877   section_offset_type
878   offset() const
879   {
880     gold_assert(this->offset_ != this->invalid_offset);
881     return this->offset_;
882   }
883
884   // Set stub offset.
885   void
886   set_offset(section_offset_type offset)
887   { this->offset_ = offset; }
888
889   // Return the stub insn.
890   const Insntype*
891   insns() const
892   { return this->stub_template()->insns; }
893
894   // Return num of stub insns.
895   unsigned int
896   insn_num() const
897   { return this->stub_template()->insn_num; }
898
899   // Get size of the stub.
900   int
901   stub_size() const
902   {
903     return this->insn_num() *
904       AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
905   }
906
907   // Write stub to output file.
908   void
909   write(unsigned char* view, section_size_type view_size)
910   { this->do_write(view, view_size); }
911
912 protected:
913   // Abstract method to be implemented by sub-classes.
914   virtual void
915   do_write(unsigned char*, section_size_type) = 0;
916
917 private:
918   // The last insn of a stub is a jump to destination insn. This field records
919   // the destination address.
920   AArch64_address destination_address_;
921   // The stub offset. Note this has difference interpretations between an
922   // Reloc_stub and an Erratum_stub. For Reloc_stub this is the offset from the
923   // beginning of the containing stub_table, whereas for Erratum_stub, this is
924   // the offset from the end of reloc_stubs.
925   section_offset_type offset_;
926   // Stub type.
927   const int type_;
928 };  // End of "Stub_base".
929
930
931 // Erratum stub class. An erratum stub differs from a reloc stub in that for
932 // each erratum occurrence, we generate an erratum stub. We never share erratum
933 // stubs, whereas for reloc stubs, different branch insns share a single reloc
934 // stub as long as the branch targets are the same. (More to the point, reloc
935 // stubs can be shared because they're used to reach a specific target, whereas
936 // erratum stubs branch back to the original control flow.)
937
938 template<int size, bool big_endian>
939 class Erratum_stub : public Stub_base<size, big_endian>
940 {
941 public:
942   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
943   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
944   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
945   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
946
947   static const int STUB_ADDR_ALIGN;
948
949   static const Insntype invalid_insn = static_cast<Insntype>(-1);
950
951   Erratum_stub(The_aarch64_relobj* relobj, int type,
952                unsigned shndx, unsigned int sh_offset)
953     : Stub_base<size, big_endian>(type), relobj_(relobj),
954       shndx_(shndx), sh_offset_(sh_offset),
955       erratum_insn_(invalid_insn),
956       erratum_address_(this->invalid_address)
957   {}
958
959   ~Erratum_stub() {}
960
961   // Return the object that contains the erratum.
962   The_aarch64_relobj*
963   relobj()
964   { return this->relobj_; }
965
966   // Get section index of the erratum.
967   unsigned int
968   shndx() const
969   { return this->shndx_; }
970
971   // Get section offset of the erratum.
972   unsigned int
973   sh_offset() const
974   { return this->sh_offset_; }
975
976   // Get the erratum insn. This is the insn located at erratum_insn_address.
977   Insntype
978   erratum_insn() const
979   {
980     gold_assert(this->erratum_insn_ != this->invalid_insn);
981     return this->erratum_insn_;
982   }
983
984   // Set the insn that the erratum happens to.
985   void
986   set_erratum_insn(Insntype insn)
987   { this->erratum_insn_ = insn; }
988
989   // For 843419, the erratum insn is ld/st xt, [xn, #uimm], which may be a
990   // relocation spot, in this case, the erratum_insn_ recorded at scanning phase
991   // is no longer the one we want to write out to the stub, update erratum_insn_
992   // with relocated version. Also note that in this case xn must not be "PC", so
993   // it is safe to move the erratum insn from the origin place to the stub. For
994   // 835769, the erratum insn is multiply-accumulate insn, which could not be a
995   // relocation spot (assertion added though).
996   void
997   update_erratum_insn(Insntype insn)
998   {
999     gold_assert(this->erratum_insn_ != this->invalid_insn);
1000     switch (this->type())
1001       {
1002       case ST_E_843419:
1003         gold_assert(Insn_utilities::aarch64_ldst_uimm(insn));
1004         gold_assert(Insn_utilities::aarch64_ldst_uimm(this->erratum_insn()));
1005         gold_assert(Insn_utilities::aarch64_rd(insn) ==
1006                     Insn_utilities::aarch64_rd(this->erratum_insn()));
1007         gold_assert(Insn_utilities::aarch64_rn(insn) ==
1008                     Insn_utilities::aarch64_rn(this->erratum_insn()));
1009         // Update plain ld/st insn with relocated insn.
1010         this->erratum_insn_ = insn;
1011         break;
1012       case ST_E_835769:
1013         gold_assert(insn == this->erratum_insn());
1014         break;
1015       default:
1016         gold_unreachable();
1017       }
1018   }
1019
1020
1021   // Return the address where an erratum must be done.
1022   AArch64_address
1023   erratum_address() const
1024   {
1025     gold_assert(this->erratum_address_ != this->invalid_address);
1026     return this->erratum_address_;
1027   }
1028
1029   // Set the address where an erratum must be done.
1030   void
1031   set_erratum_address(AArch64_address addr)
1032   { this->erratum_address_ = addr; }
1033
1034   // Comparator used to group Erratum_stubs in a set by (obj, shndx,
1035   // sh_offset). We do not include 'type' in the calculation, because there is
1036   // at most one stub type at (obj, shndx, sh_offset).
1037   bool
1038   operator<(const Erratum_stub<size, big_endian>& k) const
1039   {
1040     if (this == &k)
1041       return false;
1042     // We group stubs by relobj.
1043     if (this->relobj_ != k.relobj_)
1044       return this->relobj_ < k.relobj_;
1045     // Then by section index.
1046     if (this->shndx_ != k.shndx_)
1047       return this->shndx_ < k.shndx_;
1048     // Lastly by section offset.
1049     return this->sh_offset_ < k.sh_offset_;
1050   }
1051
1052 protected:
1053   virtual void
1054   do_write(unsigned char*, section_size_type);
1055
1056 private:
1057   // The object that needs to be fixed.
1058   The_aarch64_relobj* relobj_;
1059   // The shndx in the object that needs to be fixed.
1060   const unsigned int shndx_;
1061   // The section offset in the obejct that needs to be fixed.
1062   const unsigned int sh_offset_;
1063   // The insn to be fixed.
1064   Insntype erratum_insn_;
1065   // The address of the above insn.
1066   AArch64_address erratum_address_;
1067 };  // End of "Erratum_stub".
1068
1069
1070 // Erratum sub class to wrap additional info needed by 843419.  In fixing this
1071 // erratum, we may choose to replace 'adrp' with 'adr', in this case, we need
1072 // adrp's code position (two or three insns before erratum insn itself).
1073
1074 template<int size, bool big_endian>
1075 class E843419_stub : public Erratum_stub<size, big_endian>
1076 {
1077 public:
1078   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
1079
1080   E843419_stub(AArch64_relobj<size, big_endian>* relobj,
1081                       unsigned int shndx, unsigned int sh_offset,
1082                       unsigned int adrp_sh_offset)
1083     : Erratum_stub<size, big_endian>(relobj, ST_E_843419, shndx, sh_offset),
1084       adrp_sh_offset_(adrp_sh_offset)
1085   {}
1086
1087   unsigned int
1088   adrp_sh_offset() const
1089   { return this->adrp_sh_offset_; }
1090
1091 private:
1092   // Section offset of "adrp". (We do not need a "adrp_shndx_" field, because we
1093   // can can obtain it from its parent.)
1094   const unsigned int adrp_sh_offset_;
1095 };
1096
1097
1098 template<int size, bool big_endian>
1099 const int Erratum_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
1100
1101 // Comparator used in set definition.
1102 template<int size, bool big_endian>
1103 struct Erratum_stub_less
1104 {
1105   bool
1106   operator()(const Erratum_stub<size, big_endian>* s1,
1107              const Erratum_stub<size, big_endian>* s2) const
1108   { return *s1 < *s2; }
1109 };
1110
1111 // Erratum_stub implementation for writing stub to output file.
1112
1113 template<int size, bool big_endian>
1114 void
1115 Erratum_stub<size, big_endian>::do_write(unsigned char* view, section_size_type)
1116 {
1117   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
1118   const Insntype* insns = this->insns();
1119   uint32_t num_insns = this->insn_num();
1120   Insntype* ip = reinterpret_cast<Insntype*>(view);
1121   // For current implemented erratum 843419 and 835769, the first insn in the
1122   // stub is always a copy of the problematic insn (in 843419, the mem access
1123   // insn, in 835769, the mac insn), followed by a jump-back.
1124   elfcpp::Swap<32, big_endian>::writeval(ip, this->erratum_insn());
1125   for (uint32_t i = 1; i < num_insns; ++i)
1126     elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
1127 }
1128
1129
1130 // Reloc stub class.
1131
1132 template<int size, bool big_endian>
1133 class Reloc_stub : public Stub_base<size, big_endian>
1134 {
1135  public:
1136   typedef Reloc_stub<size, big_endian> This;
1137   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1138
1139   // Branch range. This is used to calculate the section group size, as well as
1140   // determine whether a stub is needed.
1141   static const int MAX_BRANCH_OFFSET = ((1 << 25) - 1) << 2;
1142   static const int MIN_BRANCH_OFFSET = -((1 << 25) << 2);
1143
1144   // Constant used to determine if an offset fits in the adrp instruction
1145   // encoding.
1146   static const int MAX_ADRP_IMM = (1 << 20) - 1;
1147   static const int MIN_ADRP_IMM = -(1 << 20);
1148
1149   static const int BYTES_PER_INSN = 4;
1150   static const int STUB_ADDR_ALIGN;
1151
1152   // Determine whether the offset fits in the jump/branch instruction.
1153   static bool
1154   aarch64_valid_branch_offset_p(int64_t offset)
1155   { return offset >= MIN_BRANCH_OFFSET && offset <= MAX_BRANCH_OFFSET; }
1156
1157   // Determine whether the offset fits in the adrp immediate field.
1158   static bool
1159   aarch64_valid_for_adrp_p(AArch64_address location, AArch64_address dest)
1160   {
1161     typedef AArch64_relocate_functions<size, big_endian> Reloc;
1162     int64_t adrp_imm = (Reloc::Page(dest) - Reloc::Page(location)) >> 12;
1163     return adrp_imm >= MIN_ADRP_IMM && adrp_imm <= MAX_ADRP_IMM;
1164   }
1165
1166   // Determine the stub type for a certain relocation or ST_NONE, if no stub is
1167   // needed.
1168   static int
1169   stub_type_for_reloc(unsigned int r_type, AArch64_address address,
1170                       AArch64_address target);
1171
1172   Reloc_stub(int type)
1173     : Stub_base<size, big_endian>(type)
1174   { }
1175
1176   ~Reloc_stub()
1177   { }
1178
1179   // The key class used to index the stub instance in the stub table's stub map.
1180   class Key
1181   {
1182    public:
1183     Key(int type, const Symbol* symbol, const Relobj* relobj,
1184         unsigned int r_sym, int32_t addend)
1185       : type_(type), addend_(addend)
1186     {
1187       if (symbol != NULL)
1188         {
1189           this->r_sym_ = Reloc_stub::invalid_index;
1190           this->u_.symbol = symbol;
1191         }
1192       else
1193         {
1194           gold_assert(relobj != NULL && r_sym != invalid_index);
1195           this->r_sym_ = r_sym;
1196           this->u_.relobj = relobj;
1197         }
1198     }
1199
1200     ~Key()
1201     { }
1202
1203     // Return stub type.
1204     int
1205     type() const
1206     { return this->type_; }
1207
1208     // Return the local symbol index or invalid_index.
1209     unsigned int
1210     r_sym() const
1211     { return this->r_sym_; }
1212
1213     // Return the symbol if there is one.
1214     const Symbol*
1215     symbol() const
1216     { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
1217
1218     // Return the relobj if there is one.
1219     const Relobj*
1220     relobj() const
1221     { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
1222
1223     // Whether this equals to another key k.
1224     bool
1225     eq(const Key& k) const
1226     {
1227       return ((this->type_ == k.type_)
1228               && (this->r_sym_ == k.r_sym_)
1229               && ((this->r_sym_ != Reloc_stub::invalid_index)
1230                   ? (this->u_.relobj == k.u_.relobj)
1231                   : (this->u_.symbol == k.u_.symbol))
1232               && (this->addend_ == k.addend_));
1233     }
1234
1235     // Return a hash value.
1236     size_t
1237     hash_value() const
1238     {
1239       size_t name_hash_value = gold::string_hash<char>(
1240           (this->r_sym_ != Reloc_stub::invalid_index)
1241           ? this->u_.relobj->name().c_str()
1242           : this->u_.symbol->name());
1243       // We only have 4 stub types.
1244       size_t stub_type_hash_value = 0x03 & this->type_;
1245       return (name_hash_value
1246               ^ stub_type_hash_value
1247               ^ ((this->r_sym_ & 0x3fff) << 2)
1248               ^ ((this->addend_ & 0xffff) << 16));
1249     }
1250
1251     // Functors for STL associative containers.
1252     struct hash
1253     {
1254       size_t
1255       operator()(const Key& k) const
1256       { return k.hash_value(); }
1257     };
1258
1259     struct equal_to
1260     {
1261       bool
1262       operator()(const Key& k1, const Key& k2) const
1263       { return k1.eq(k2); }
1264     };
1265
1266    private:
1267     // Stub type.
1268     const int type_;
1269     // If this is a local symbol, this is the index in the defining object.
1270     // Otherwise, it is invalid_index for a global symbol.
1271     unsigned int r_sym_;
1272     // If r_sym_ is an invalid index, this points to a global symbol.
1273     // Otherwise, it points to a relobj.  We used the unsized and target
1274     // independent Symbol and Relobj classes instead of Sized_symbol<32> and
1275     // Arm_relobj, in order to avoid making the stub class a template
1276     // as most of the stub machinery is endianness-neutral.  However, it
1277     // may require a bit of casting done by users of this class.
1278     union
1279     {
1280       const Symbol* symbol;
1281       const Relobj* relobj;
1282     } u_;
1283     // Addend associated with a reloc.
1284     int32_t addend_;
1285   };  // End of inner class Reloc_stub::Key
1286
1287  protected:
1288   // This may be overridden in the child class.
1289   virtual void
1290   do_write(unsigned char*, section_size_type);
1291
1292  private:
1293   static const unsigned int invalid_index = static_cast<unsigned int>(-1);
1294 };  // End of Reloc_stub
1295
1296 template<int size, bool big_endian>
1297 const int Reloc_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
1298
1299 // Write data to output file.
1300
1301 template<int size, bool big_endian>
1302 void
1303 Reloc_stub<size, big_endian>::
1304 do_write(unsigned char* view, section_size_type)
1305 {
1306   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
1307   const uint32_t* insns = this->insns();
1308   uint32_t num_insns = this->insn_num();
1309   Insntype* ip = reinterpret_cast<Insntype*>(view);
1310   for (uint32_t i = 0; i < num_insns; ++i)
1311     elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
1312 }
1313
1314
1315 // Determine the stub type for a certain relocation or ST_NONE, if no stub is
1316 // needed.
1317
1318 template<int size, bool big_endian>
1319 inline int
1320 Reloc_stub<size, big_endian>::stub_type_for_reloc(
1321     unsigned int r_type, AArch64_address location, AArch64_address dest)
1322 {
1323   int64_t branch_offset = 0;
1324   switch(r_type)
1325     {
1326     case elfcpp::R_AARCH64_CALL26:
1327     case elfcpp::R_AARCH64_JUMP26:
1328       branch_offset = dest - location;
1329       break;
1330     default:
1331       gold_unreachable();
1332     }
1333
1334   if (aarch64_valid_branch_offset_p(branch_offset))
1335     return ST_NONE;
1336
1337   if (aarch64_valid_for_adrp_p(location, dest))
1338     return ST_ADRP_BRANCH;
1339
1340   // Always use PC-relative addressing in case of -shared or -pie.
1341   if (parameters->options().output_is_position_independent())
1342     return ST_LONG_BRANCH_PCREL;
1343
1344   // This saves 2 insns per stub, compared to ST_LONG_BRANCH_PCREL.
1345   // But is only applicable to non-shared or non-pie.
1346   return ST_LONG_BRANCH_ABS;
1347 }
1348
1349 // A class to hold stubs for the ARM target.
1350
1351 template<int size, bool big_endian>
1352 class Stub_table : public Output_data
1353 {
1354  public:
1355   typedef Target_aarch64<size, big_endian> The_target_aarch64;
1356   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1357   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
1358   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
1359   typedef Reloc_stub<size, big_endian> The_reloc_stub;
1360   typedef typename The_reloc_stub::Key The_reloc_stub_key;
1361   typedef Erratum_stub<size, big_endian> The_erratum_stub;
1362   typedef Erratum_stub_less<size, big_endian> The_erratum_stub_less;
1363   typedef typename The_reloc_stub_key::hash The_reloc_stub_key_hash;
1364   typedef typename The_reloc_stub_key::equal_to The_reloc_stub_key_equal_to;
1365   typedef Stub_table<size, big_endian> The_stub_table;
1366   typedef Unordered_map<The_reloc_stub_key, The_reloc_stub*,
1367                         The_reloc_stub_key_hash, The_reloc_stub_key_equal_to>
1368                         Reloc_stub_map;
1369   typedef typename Reloc_stub_map::const_iterator Reloc_stub_map_const_iter;
1370   typedef Relocate_info<size, big_endian> The_relocate_info;
1371
1372   typedef std::set<The_erratum_stub*, The_erratum_stub_less> Erratum_stub_set;
1373   typedef typename Erratum_stub_set::iterator Erratum_stub_set_iter;
1374
1375   Stub_table(The_aarch64_input_section* owner)
1376     : Output_data(), owner_(owner), reloc_stubs_size_(0),
1377       erratum_stubs_size_(0), prev_data_size_(0)
1378   { }
1379
1380   ~Stub_table()
1381   { }
1382
1383   The_aarch64_input_section*
1384   owner() const
1385   { return owner_; }
1386
1387   // Whether this stub table is empty.
1388   bool
1389   empty() const
1390   { return reloc_stubs_.empty() && erratum_stubs_.empty(); }
1391
1392   // Return the current data size.
1393   off_t
1394   current_data_size() const
1395   { return this->current_data_size_for_child(); }
1396
1397   // Add a STUB using KEY.  The caller is responsible for avoiding addition
1398   // if a STUB with the same key has already been added.
1399   void
1400   add_reloc_stub(The_reloc_stub* stub, const The_reloc_stub_key& key);
1401
1402   // Add an erratum stub into the erratum stub set. The set is ordered by
1403   // (relobj, shndx, sh_offset).
1404   void
1405   add_erratum_stub(The_erratum_stub* stub);
1406
1407   // Find if such erratum exists for any given (obj, shndx, sh_offset).
1408   The_erratum_stub*
1409   find_erratum_stub(The_aarch64_relobj* a64relobj,
1410                     unsigned int shndx, unsigned int sh_offset);
1411
1412   // Find all the erratums for a given input section. The return value is a pair
1413   // of iterators [begin, end).
1414   std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
1415   find_erratum_stubs_for_input_section(The_aarch64_relobj* a64relobj,
1416                                        unsigned int shndx);
1417
1418   // Compute the erratum stub address.
1419   AArch64_address
1420   erratum_stub_address(The_erratum_stub* stub) const
1421   {
1422     AArch64_address r = align_address(this->address() + this->reloc_stubs_size_,
1423                                       The_erratum_stub::STUB_ADDR_ALIGN);
1424     r += stub->offset();
1425     return r;
1426   }
1427
1428   // Finalize stubs. No-op here, just for completeness.
1429   void
1430   finalize_stubs()
1431   { }
1432
1433   // Look up a relocation stub using KEY. Return NULL if there is none.
1434   The_reloc_stub*
1435   find_reloc_stub(The_reloc_stub_key& key)
1436   {
1437     Reloc_stub_map_const_iter p = this->reloc_stubs_.find(key);
1438     return (p != this->reloc_stubs_.end()) ? p->second : NULL;
1439   }
1440
1441   // Relocate stubs in this stub table.
1442   void
1443   relocate_stubs(const The_relocate_info*,
1444                  The_target_aarch64*,
1445                  Output_section*,
1446                  unsigned char*,
1447                  AArch64_address,
1448                  section_size_type);
1449
1450   // Update data size at the end of a relaxation pass.  Return true if data size
1451   // is different from that of the previous relaxation pass.
1452   bool
1453   update_data_size_changed_p()
1454   {
1455     // No addralign changed here.
1456     off_t s = align_address(this->reloc_stubs_size_,
1457                             The_erratum_stub::STUB_ADDR_ALIGN)
1458               + this->erratum_stubs_size_;
1459     bool changed = (s != this->prev_data_size_);
1460     this->prev_data_size_ = s;
1461     return changed;
1462   }
1463
1464  protected:
1465   // Write out section contents.
1466   void
1467   do_write(Output_file*);
1468
1469   // Return the required alignment.
1470   uint64_t
1471   do_addralign() const
1472   {
1473     return std::max(The_reloc_stub::STUB_ADDR_ALIGN,
1474                     The_erratum_stub::STUB_ADDR_ALIGN);
1475   }
1476
1477   // Reset address and file offset.
1478   void
1479   do_reset_address_and_file_offset()
1480   { this->set_current_data_size_for_child(this->prev_data_size_); }
1481
1482   // Set final data size.
1483   void
1484   set_final_data_size()
1485   { this->set_data_size(this->current_data_size()); }
1486
1487  private:
1488   // Relocate one stub.
1489   void
1490   relocate_stub(The_reloc_stub*,
1491                 const The_relocate_info*,
1492                 The_target_aarch64*,
1493                 Output_section*,
1494                 unsigned char*,
1495                 AArch64_address,
1496                 section_size_type);
1497
1498  private:
1499   // Owner of this stub table.
1500   The_aarch64_input_section* owner_;
1501   // The relocation stubs.
1502   Reloc_stub_map reloc_stubs_;
1503   // The erratum stubs.
1504   Erratum_stub_set erratum_stubs_;
1505   // Size of reloc stubs.
1506   off_t reloc_stubs_size_;
1507   // Size of erratum stubs.
1508   off_t erratum_stubs_size_;
1509   // data size of this in the previous pass.
1510   off_t prev_data_size_;
1511 };  // End of Stub_table
1512
1513
1514 // Add an erratum stub into the erratum stub set. The set is ordered by
1515 // (relobj, shndx, sh_offset).
1516
1517 template<int size, bool big_endian>
1518 void
1519 Stub_table<size, big_endian>::add_erratum_stub(The_erratum_stub* stub)
1520 {
1521   std::pair<Erratum_stub_set_iter, bool> ret =
1522     this->erratum_stubs_.insert(stub);
1523   gold_assert(ret.second);
1524   this->erratum_stubs_size_ = align_address(
1525         this->erratum_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
1526   stub->set_offset(this->erratum_stubs_size_);
1527   this->erratum_stubs_size_ += stub->stub_size();
1528 }
1529
1530
1531 // Find if such erratum exists for given (obj, shndx, sh_offset).
1532
1533 template<int size, bool big_endian>
1534 Erratum_stub<size, big_endian>*
1535 Stub_table<size, big_endian>::find_erratum_stub(
1536     The_aarch64_relobj* a64relobj, unsigned int shndx, unsigned int sh_offset)
1537 {
1538   // A dummy object used as key to search in the set.
1539   The_erratum_stub key(a64relobj, ST_NONE,
1540                          shndx, sh_offset);
1541   Erratum_stub_set_iter i = this->erratum_stubs_.find(&key);
1542   if (i != this->erratum_stubs_.end())
1543     {
1544         The_erratum_stub* stub(*i);
1545         gold_assert(stub->erratum_insn() != 0);
1546         return stub;
1547     }
1548   return NULL;
1549 }
1550
1551
1552 // Find all the errata for a given input section. The return value is a pair of
1553 // iterators [begin, end).
1554
1555 template<int size, bool big_endian>
1556 std::pair<typename Stub_table<size, big_endian>::Erratum_stub_set_iter,
1557           typename Stub_table<size, big_endian>::Erratum_stub_set_iter>
1558 Stub_table<size, big_endian>::find_erratum_stubs_for_input_section(
1559     The_aarch64_relobj* a64relobj, unsigned int shndx)
1560 {
1561   typedef std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter> Result_pair;
1562   Erratum_stub_set_iter start, end;
1563   The_erratum_stub low_key(a64relobj, ST_NONE, shndx, 0);
1564   start = this->erratum_stubs_.lower_bound(&low_key);
1565   if (start == this->erratum_stubs_.end())
1566     return Result_pair(this->erratum_stubs_.end(),
1567                        this->erratum_stubs_.end());
1568   end = start;
1569   while (end != this->erratum_stubs_.end() &&
1570          (*end)->relobj() == a64relobj && (*end)->shndx() == shndx)
1571     ++end;
1572   return Result_pair(start, end);
1573 }
1574
1575
1576 // Add a STUB using KEY.  The caller is responsible for avoiding addition
1577 // if a STUB with the same key has already been added.
1578
1579 template<int size, bool big_endian>
1580 void
1581 Stub_table<size, big_endian>::add_reloc_stub(
1582     The_reloc_stub* stub, const The_reloc_stub_key& key)
1583 {
1584   gold_assert(stub->type() == key.type());
1585   this->reloc_stubs_[key] = stub;
1586
1587   // Assign stub offset early.  We can do this because we never remove
1588   // reloc stubs and they are in the beginning of the stub table.
1589   this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_,
1590                                           The_reloc_stub::STUB_ADDR_ALIGN);
1591   stub->set_offset(this->reloc_stubs_size_);
1592   this->reloc_stubs_size_ += stub->stub_size();
1593 }
1594
1595
1596 // Relocate all stubs in this stub table.
1597
1598 template<int size, bool big_endian>
1599 void
1600 Stub_table<size, big_endian>::
1601 relocate_stubs(const The_relocate_info* relinfo,
1602                The_target_aarch64* target_aarch64,
1603                Output_section* output_section,
1604                unsigned char* view,
1605                AArch64_address address,
1606                section_size_type view_size)
1607 {
1608   // "view_size" is the total size of the stub_table.
1609   gold_assert(address == this->address() &&
1610               view_size == static_cast<section_size_type>(this->data_size()));
1611   for(Reloc_stub_map_const_iter p = this->reloc_stubs_.begin();
1612       p != this->reloc_stubs_.end(); ++p)
1613     relocate_stub(p->second, relinfo, target_aarch64, output_section,
1614                   view, address, view_size);
1615
1616   // Just for convenience.
1617   const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
1618
1619   // Now 'relocate' erratum stubs.
1620   for(Erratum_stub_set_iter i = this->erratum_stubs_.begin();
1621       i != this->erratum_stubs_.end(); ++i)
1622     {
1623       AArch64_address stub_address = this->erratum_stub_address(*i);
1624       // The address of "b" in the stub that is to be "relocated".
1625       AArch64_address stub_b_insn_address;
1626       // Branch offset that is to be filled in "b" insn.
1627       int b_offset = 0;
1628       switch ((*i)->type())
1629         {
1630         case ST_E_843419:
1631         case ST_E_835769:
1632           // The 1st insn of the erratum could be a relocation spot,
1633           // in this case we need to fix it with
1634           // "(*i)->erratum_insn()".
1635           elfcpp::Swap<32, big_endian>::writeval(
1636               view + (stub_address - this->address()),
1637               (*i)->erratum_insn());
1638           // For the erratum, the 2nd insn is a b-insn to be patched
1639           // (relocated).
1640           stub_b_insn_address = stub_address + 1 * BPI;
1641           b_offset = (*i)->destination_address() - stub_b_insn_address;
1642           AArch64_relocate_functions<size, big_endian>::construct_b(
1643               view + (stub_b_insn_address - this->address()),
1644               ((unsigned int)(b_offset)) & 0xfffffff);
1645           break;
1646         default:
1647           gold_unreachable();
1648           break;
1649         }
1650     }
1651 }
1652
1653
1654 // Relocate one stub.  This is a helper for Stub_table::relocate_stubs().
1655
1656 template<int size, bool big_endian>
1657 void
1658 Stub_table<size, big_endian>::
1659 relocate_stub(The_reloc_stub* stub,
1660               const The_relocate_info* relinfo,
1661               The_target_aarch64* target_aarch64,
1662               Output_section* output_section,
1663               unsigned char* view,
1664               AArch64_address address,
1665               section_size_type view_size)
1666 {
1667   // "offset" is the offset from the beginning of the stub_table.
1668   section_size_type offset = stub->offset();
1669   section_size_type stub_size = stub->stub_size();
1670   // "view_size" is the total size of the stub_table.
1671   gold_assert(offset + stub_size <= view_size);
1672
1673   target_aarch64->relocate_stub(stub, relinfo, output_section,
1674                                 view + offset, address + offset, view_size);
1675 }
1676
1677
1678 // Write out the stubs to file.
1679
1680 template<int size, bool big_endian>
1681 void
1682 Stub_table<size, big_endian>::do_write(Output_file* of)
1683 {
1684   off_t offset = this->offset();
1685   const section_size_type oview_size =
1686     convert_to_section_size_type(this->data_size());
1687   unsigned char* const oview = of->get_output_view(offset, oview_size);
1688
1689   // Write relocation stubs.
1690   for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
1691       p != this->reloc_stubs_.end(); ++p)
1692     {
1693       The_reloc_stub* stub = p->second;
1694       AArch64_address address = this->address() + stub->offset();
1695       gold_assert(address ==
1696                   align_address(address, The_reloc_stub::STUB_ADDR_ALIGN));
1697       stub->write(oview + stub->offset(), stub->stub_size());
1698     }
1699
1700   // Write erratum stubs.
1701   unsigned int erratum_stub_start_offset =
1702     align_address(this->reloc_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
1703   for (typename Erratum_stub_set::iterator p = this->erratum_stubs_.begin();
1704        p != this->erratum_stubs_.end(); ++p)
1705     {
1706       The_erratum_stub* stub(*p);
1707       stub->write(oview + erratum_stub_start_offset + stub->offset(),
1708                   stub->stub_size());
1709     }
1710
1711   of->write_output_view(this->offset(), oview_size, oview);
1712 }
1713
1714
1715 // AArch64_relobj class.
1716
1717 template<int size, bool big_endian>
1718 class AArch64_relobj : public Sized_relobj_file<size, big_endian>
1719 {
1720  public:
1721   typedef AArch64_relobj<size, big_endian> This;
1722   typedef Target_aarch64<size, big_endian> The_target_aarch64;
1723   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
1724   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1725   typedef Stub_table<size, big_endian> The_stub_table;
1726   typedef Erratum_stub<size, big_endian> The_erratum_stub;
1727   typedef typename The_stub_table::Erratum_stub_set_iter Erratum_stub_set_iter;
1728   typedef std::vector<The_stub_table*> Stub_table_list;
1729   static const AArch64_address invalid_address =
1730       static_cast<AArch64_address>(-1);
1731
1732   AArch64_relobj(const std::string& name, Input_file* input_file, off_t offset,
1733                  const typename elfcpp::Ehdr<size, big_endian>& ehdr)
1734     : Sized_relobj_file<size, big_endian>(name, input_file, offset, ehdr),
1735       stub_tables_()
1736   { }
1737
1738   ~AArch64_relobj()
1739   { }
1740
1741   // Return the stub table of the SHNDX-th section if there is one.
1742   The_stub_table*
1743   stub_table(unsigned int shndx) const
1744   {
1745     gold_assert(shndx < this->stub_tables_.size());
1746     return this->stub_tables_[shndx];
1747   }
1748
1749   // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1750   void
1751   set_stub_table(unsigned int shndx, The_stub_table* stub_table)
1752   {
1753     gold_assert(shndx < this->stub_tables_.size());
1754     this->stub_tables_[shndx] = stub_table;
1755   }
1756
1757   // Entrance to errata scanning.
1758   void
1759   scan_errata(unsigned int shndx,
1760               const elfcpp::Shdr<size, big_endian>&,
1761               Output_section*, const Symbol_table*,
1762               The_target_aarch64*);
1763
1764   // Scan all relocation sections for stub generation.
1765   void
1766   scan_sections_for_stubs(The_target_aarch64*, const Symbol_table*,
1767                           const Layout*);
1768
1769   // Whether a section is a scannable text section.
1770   bool
1771   text_section_is_scannable(const elfcpp::Shdr<size, big_endian>&, unsigned int,
1772                             const Output_section*, const Symbol_table*);
1773
1774   // Convert regular input section with index SHNDX to a relaxed section.
1775   void
1776   convert_input_section_to_relaxed_section(unsigned shndx)
1777   {
1778     // The stubs have relocations and we need to process them after writing
1779     // out the stubs.  So relocation now must follow section write.
1780     this->set_section_offset(shndx, -1ULL);
1781     this->set_relocs_must_follow_section_writes();
1782   }
1783
1784   // Structure for mapping symbol position.
1785   struct Mapping_symbol_position
1786   {
1787     Mapping_symbol_position(unsigned int shndx, AArch64_address offset):
1788       shndx_(shndx), offset_(offset)
1789     {}
1790
1791     // "<" comparator used in ordered_map container.
1792     bool
1793     operator<(const Mapping_symbol_position& p) const
1794     {
1795       return (this->shndx_ < p.shndx_
1796               || (this->shndx_ == p.shndx_ && this->offset_ < p.offset_));
1797     }
1798
1799     // Section index.
1800     unsigned int shndx_;
1801
1802     // Section offset.
1803     AArch64_address offset_;
1804   };
1805
1806   typedef std::map<Mapping_symbol_position, char> Mapping_symbol_info;
1807
1808  protected:
1809   // Post constructor setup.
1810   void
1811   do_setup()
1812   {
1813     // Call parent's setup method.
1814     Sized_relobj_file<size, big_endian>::do_setup();
1815
1816     // Initialize look-up tables.
1817     this->stub_tables_.resize(this->shnum());
1818   }
1819
1820   virtual void
1821   do_relocate_sections(
1822       const Symbol_table* symtab, const Layout* layout,
1823       const unsigned char* pshdrs, Output_file* of,
1824       typename Sized_relobj_file<size, big_endian>::Views* pviews);
1825
1826   // Count local symbols and (optionally) record mapping info.
1827   virtual void
1828   do_count_local_symbols(Stringpool_template<char>*,
1829                          Stringpool_template<char>*);
1830
1831  private:
1832   // Fix all errata in the object.
1833   void
1834   fix_errata(typename Sized_relobj_file<size, big_endian>::Views* pviews);
1835
1836   // Try to fix erratum 843419 in an optimized way. Return true if patch is
1837   // applied.
1838   bool
1839   try_fix_erratum_843419_optimized(
1840       The_erratum_stub*,
1841       typename Sized_relobj_file<size, big_endian>::View_size&);
1842
1843   // Whether a section needs to be scanned for relocation stubs.
1844   bool
1845   section_needs_reloc_stub_scanning(const elfcpp::Shdr<size, big_endian>&,
1846                                     const Relobj::Output_sections&,
1847                                     const Symbol_table*, const unsigned char*);
1848
1849   // List of stub tables.
1850   Stub_table_list stub_tables_;
1851
1852   // Mapping symbol information sorted by (section index, section_offset).
1853   Mapping_symbol_info mapping_symbol_info_;
1854 };  // End of AArch64_relobj
1855
1856
1857 // Override to record mapping symbol information.
1858 template<int size, bool big_endian>
1859 void
1860 AArch64_relobj<size, big_endian>::do_count_local_symbols(
1861     Stringpool_template<char>* pool, Stringpool_template<char>* dynpool)
1862 {
1863   Sized_relobj_file<size, big_endian>::do_count_local_symbols(pool, dynpool);
1864
1865   // Only erratum-fixing work needs mapping symbols, so skip this time consuming
1866   // processing if not fixing erratum.
1867   if (!parameters->options().fix_cortex_a53_843419()
1868       && !parameters->options().fix_cortex_a53_835769())
1869     return;
1870
1871   const unsigned int loccount = this->local_symbol_count();
1872   if (loccount == 0)
1873     return;
1874
1875   // Read the symbol table section header.
1876   const unsigned int symtab_shndx = this->symtab_shndx();
1877   elfcpp::Shdr<size, big_endian>
1878       symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
1879   gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
1880
1881   // Read the local symbols.
1882   const int sym_size =elfcpp::Elf_sizes<size>::sym_size;
1883   gold_assert(loccount == symtabshdr.get_sh_info());
1884   off_t locsize = loccount * sym_size;
1885   const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
1886                                               locsize, true, true);
1887
1888   // For mapping symbol processing, we need to read the symbol names.
1889   unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
1890   if (strtab_shndx >= this->shnum())
1891     {
1892       this->error(_("invalid symbol table name index: %u"), strtab_shndx);
1893       return;
1894     }
1895
1896   elfcpp::Shdr<size, big_endian>
1897     strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
1898   if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
1899     {
1900       this->error(_("symbol table name section has wrong type: %u"),
1901                   static_cast<unsigned int>(strtabshdr.get_sh_type()));
1902       return;
1903     }
1904
1905   const char* pnames =
1906     reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
1907                                                  strtabshdr.get_sh_size(),
1908                                                  false, false));
1909
1910   // Skip the first dummy symbol.
1911   psyms += sym_size;
1912   typename Sized_relobj_file<size, big_endian>::Local_values*
1913     plocal_values = this->local_values();
1914   for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
1915     {
1916       elfcpp::Sym<size, big_endian> sym(psyms);
1917       Symbol_value<size>& lv((*plocal_values)[i]);
1918       AArch64_address input_value = lv.input_value();
1919
1920       // Check to see if this is a mapping symbol. AArch64 mapping symbols are
1921       // defined in "ELF for the ARM 64-bit Architecture", Table 4-4, Mapping
1922       // symbols.
1923       // Mapping symbols could be one of the following 4 forms -
1924       //   a) $x
1925       //   b) $x.<any...>
1926       //   c) $d
1927       //   d) $d.<any...>
1928       const char* sym_name = pnames + sym.get_st_name();
1929       if (sym_name[0] == '$' && (sym_name[1] == 'x' || sym_name[1] == 'd')
1930           && (sym_name[2] == '\0' || sym_name[2] == '.'))
1931         {
1932           bool is_ordinary;
1933           unsigned int input_shndx =
1934             this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
1935           gold_assert(is_ordinary);
1936
1937           Mapping_symbol_position msp(input_shndx, input_value);
1938           // Insert mapping_symbol_info into map whose ordering is defined by
1939           // (shndx, offset_within_section).
1940           this->mapping_symbol_info_[msp] = sym_name[1];
1941         }
1942    }
1943 }
1944
1945
1946 // Fix all errata in the object.
1947
1948 template<int size, bool big_endian>
1949 void
1950 AArch64_relobj<size, big_endian>::fix_errata(
1951     typename Sized_relobj_file<size, big_endian>::Views* pviews)
1952 {
1953   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
1954   unsigned int shnum = this->shnum();
1955   for (unsigned int i = 1; i < shnum; ++i)
1956     {
1957       The_stub_table* stub_table = this->stub_table(i);
1958       if (!stub_table)
1959         continue;
1960       std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
1961         ipair(stub_table->find_erratum_stubs_for_input_section(this, i));
1962       Erratum_stub_set_iter p = ipair.first, end = ipair.second;
1963       while (p != end)
1964         {
1965           The_erratum_stub* stub = *p;
1966           typename Sized_relobj_file<size, big_endian>::View_size&
1967             pview((*pviews)[i]);
1968
1969           // Double check data before fix.
1970           gold_assert(pview.address + stub->sh_offset()
1971                       == stub->erratum_address());
1972
1973           // Update previously recorded erratum insn with relocated
1974           // version.
1975           Insntype* ip =
1976             reinterpret_cast<Insntype*>(pview.view + stub->sh_offset());
1977           Insntype insn_to_fix = ip[0];
1978           stub->update_erratum_insn(insn_to_fix);
1979
1980           // First try to see if erratum is 843419 and if it can be fixed
1981           // without using branch-to-stub.
1982           if (!try_fix_erratum_843419_optimized(stub, pview))
1983             {
1984               // Replace the erratum insn with a branch-to-stub.
1985               AArch64_address stub_address =
1986                 stub_table->erratum_stub_address(stub);
1987               unsigned int b_offset = stub_address - stub->erratum_address();
1988               AArch64_relocate_functions<size, big_endian>::construct_b(
1989                 pview.view + stub->sh_offset(), b_offset & 0xfffffff);
1990             }
1991           ++p;
1992         }
1993     }
1994 }
1995
1996
1997 // This is an optimization for 843419. This erratum requires the sequence begin
1998 // with 'adrp', when final value calculated by adrp fits in adr, we can just
1999 // replace 'adrp' with 'adr', so we save 2 jumps per occurrence. (Note, however,
2000 // in this case, we do not delete the erratum stub (too late to do so), it is
2001 // merely generated without ever being called.)
2002
2003 template<int size, bool big_endian>
2004 bool
2005 AArch64_relobj<size, big_endian>::try_fix_erratum_843419_optimized(
2006     The_erratum_stub* stub,
2007     typename Sized_relobj_file<size, big_endian>::View_size& pview)
2008 {
2009   if (stub->type() != ST_E_843419)
2010     return false;
2011
2012   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
2013   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
2014   E843419_stub<size, big_endian>* e843419_stub =
2015     reinterpret_cast<E843419_stub<size, big_endian>*>(stub);
2016   AArch64_address pc = pview.address + e843419_stub->adrp_sh_offset();
2017   unsigned int adrp_offset = e843419_stub->adrp_sh_offset ();
2018   Insntype* adrp_view = reinterpret_cast<Insntype*>(pview.view + adrp_offset);
2019   Insntype adrp_insn = adrp_view[0];
2020
2021   // If the instruction at adrp_sh_offset is "mrs R, tpidr_el0", it may come
2022   // from IE -> LE relaxation etc.  This is a side-effect of TLS relaxation that
2023   // ADRP has been turned into MRS, there is no erratum risk anymore.
2024   // Therefore, we return true to avoid doing unnecessary branch-to-stub.
2025   if (Insn_utilities::is_mrs_tpidr_el0(adrp_insn))
2026     return true;
2027
2028   // If the instruction at adrp_sh_offset is not ADRP and the instruction before
2029   // it is "mrs R, tpidr_el0", it may come from LD -> LE relaxation etc.
2030   // Like the above case, there is no erratum risk any more, we can safely
2031   // return true.
2032   if (!Insn_utilities::is_adrp(adrp_insn) && adrp_offset)
2033     {
2034       Insntype* prev_view
2035         = reinterpret_cast<Insntype*>(pview.view + adrp_offset - 4);
2036       Insntype prev_insn = prev_view[0];
2037
2038       if (Insn_utilities::is_mrs_tpidr_el0(prev_insn))
2039         return true;
2040     }
2041
2042   /* If we reach here, the first instruction must be ADRP.  */
2043   gold_assert(Insn_utilities::is_adrp(adrp_insn));
2044   // Get adrp 33-bit signed imm value.
2045   int64_t adrp_imm = Insn_utilities::
2046     aarch64_adrp_decode_imm(adrp_insn);
2047   // adrp - final value transferred to target register is calculated as:
2048   //     PC[11:0] = Zeros(12)
2049   //     adrp_dest_value = PC + adrp_imm;
2050   int64_t adrp_dest_value = (pc & ~((1 << 12) - 1)) + adrp_imm;
2051   // adr -final value transferred to target register is calucalted as:
2052   //     PC + adr_imm
2053   // So we have:
2054   //     PC + adr_imm = adrp_dest_value
2055   //   ==>
2056   //     adr_imm = adrp_dest_value - PC
2057   int64_t adr_imm = adrp_dest_value - pc;
2058   // Check if imm fits in adr (21-bit signed).
2059   if (-(1 << 20) <= adr_imm && adr_imm < (1 << 20))
2060     {
2061       // Convert 'adrp' into 'adr'.
2062       Insntype adr_insn = adrp_insn & ((1u << 31) - 1);
2063       adr_insn = Insn_utilities::
2064         aarch64_adr_encode_imm(adr_insn, adr_imm);
2065       elfcpp::Swap<32, big_endian>::writeval(adrp_view, adr_insn);
2066       return true;
2067     }
2068   return false;
2069 }
2070
2071
2072 // Relocate sections.
2073
2074 template<int size, bool big_endian>
2075 void
2076 AArch64_relobj<size, big_endian>::do_relocate_sections(
2077     const Symbol_table* symtab, const Layout* layout,
2078     const unsigned char* pshdrs, Output_file* of,
2079     typename Sized_relobj_file<size, big_endian>::Views* pviews)
2080 {
2081   // Relocate the section data.
2082   this->relocate_section_range(symtab, layout, pshdrs, of, pviews,
2083                                1, this->shnum() - 1);
2084
2085   // We do not generate stubs if doing a relocatable link.
2086   if (parameters->options().relocatable())
2087     return;
2088
2089   if (parameters->options().fix_cortex_a53_843419()
2090       || parameters->options().fix_cortex_a53_835769())
2091     this->fix_errata(pviews);
2092
2093   Relocate_info<size, big_endian> relinfo;
2094   relinfo.symtab = symtab;
2095   relinfo.layout = layout;
2096   relinfo.object = this;
2097
2098   // Relocate stub tables.
2099   unsigned int shnum = this->shnum();
2100   The_target_aarch64* target = The_target_aarch64::current_target();
2101
2102   for (unsigned int i = 1; i < shnum; ++i)
2103     {
2104       The_aarch64_input_section* aarch64_input_section =
2105           target->find_aarch64_input_section(this, i);
2106       if (aarch64_input_section != NULL
2107           && aarch64_input_section->is_stub_table_owner()
2108           && !aarch64_input_section->stub_table()->empty())
2109         {
2110           Output_section* os = this->output_section(i);
2111           gold_assert(os != NULL);
2112
2113           relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
2114           relinfo.reloc_shdr = NULL;
2115           relinfo.data_shndx = i;
2116           relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<size>::shdr_size;
2117
2118           typename Sized_relobj_file<size, big_endian>::View_size&
2119               view_struct = (*pviews)[i];
2120           gold_assert(view_struct.view != NULL);
2121
2122           The_stub_table* stub_table = aarch64_input_section->stub_table();
2123           off_t offset = stub_table->address() - view_struct.address;
2124           unsigned char* view = view_struct.view + offset;
2125           AArch64_address address = stub_table->address();
2126           section_size_type view_size = stub_table->data_size();
2127           stub_table->relocate_stubs(&relinfo, target, os, view, address,
2128                                      view_size);
2129         }
2130     }
2131 }
2132
2133
2134 // Determine if an input section is scannable for stub processing.  SHDR is
2135 // the header of the section and SHNDX is the section index.  OS is the output
2136 // section for the input section and SYMTAB is the global symbol table used to
2137 // look up ICF information.
2138
2139 template<int size, bool big_endian>
2140 bool
2141 AArch64_relobj<size, big_endian>::text_section_is_scannable(
2142     const elfcpp::Shdr<size, big_endian>& text_shdr,
2143     unsigned int text_shndx,
2144     const Output_section* os,
2145     const Symbol_table* symtab)
2146 {
2147   // Skip any empty sections, unallocated sections or sections whose
2148   // type are not SHT_PROGBITS.
2149   if (text_shdr.get_sh_size() == 0
2150       || (text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
2151       || text_shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
2152     return false;
2153
2154   // Skip any discarded or ICF'ed sections.
2155   if (os == NULL || symtab->is_section_folded(this, text_shndx))
2156     return false;
2157
2158   // Skip exception frame.
2159   if (strcmp(os->name(), ".eh_frame") == 0)
2160     return false ;
2161
2162   gold_assert(!this->is_output_section_offset_invalid(text_shndx) ||
2163               os->find_relaxed_input_section(this, text_shndx) != NULL);
2164
2165   return true;
2166 }
2167
2168
2169 // Determine if we want to scan the SHNDX-th section for relocation stubs.
2170 // This is a helper for AArch64_relobj::scan_sections_for_stubs().
2171
2172 template<int size, bool big_endian>
2173 bool
2174 AArch64_relobj<size, big_endian>::section_needs_reloc_stub_scanning(
2175     const elfcpp::Shdr<size, big_endian>& shdr,
2176     const Relobj::Output_sections& out_sections,
2177     const Symbol_table* symtab,
2178     const unsigned char* pshdrs)
2179 {
2180   unsigned int sh_type = shdr.get_sh_type();
2181   if (sh_type != elfcpp::SHT_RELA)
2182     return false;
2183
2184   // Ignore empty section.
2185   off_t sh_size = shdr.get_sh_size();
2186   if (sh_size == 0)
2187     return false;
2188
2189   // Ignore reloc section with unexpected symbol table.  The
2190   // error will be reported in the final link.
2191   if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
2192     return false;
2193
2194   gold_assert(sh_type == elfcpp::SHT_RELA);
2195   unsigned int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
2196
2197   // Ignore reloc section with unexpected entsize or uneven size.
2198   // The error will be reported in the final link.
2199   if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
2200     return false;
2201
2202   // Ignore reloc section with bad info.  This error will be
2203   // reported in the final link.
2204   unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_info());
2205   if (text_shndx >= this->shnum())
2206     return false;
2207
2208   const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
2209   const elfcpp::Shdr<size, big_endian> text_shdr(pshdrs +
2210                                                  text_shndx * shdr_size);
2211   return this->text_section_is_scannable(text_shdr, text_shndx,
2212                                          out_sections[text_shndx], symtab);
2213 }
2214
2215
2216 // Scan section SHNDX for erratum 843419 and 835769.
2217
2218 template<int size, bool big_endian>
2219 void
2220 AArch64_relobj<size, big_endian>::scan_errata(
2221     unsigned int shndx, const elfcpp::Shdr<size, big_endian>& shdr,
2222     Output_section* os, const Symbol_table* symtab,
2223     The_target_aarch64* target)
2224 {
2225   if (shdr.get_sh_size() == 0
2226       || (shdr.get_sh_flags() &
2227           (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR)) == 0
2228       || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
2229     return;
2230
2231   if (!os || symtab->is_section_folded(this, shndx)) return;
2232
2233   AArch64_address output_offset = this->get_output_section_offset(shndx);
2234   AArch64_address output_address;
2235   if (output_offset != invalid_address)
2236     output_address = os->address() + output_offset;
2237   else
2238     {
2239       const Output_relaxed_input_section* poris =
2240         os->find_relaxed_input_section(this, shndx);
2241       if (!poris) return;
2242       output_address = poris->address();
2243     }
2244
2245   section_size_type input_view_size = 0;
2246   const unsigned char* input_view =
2247     this->section_contents(shndx, &input_view_size, false);
2248
2249   Mapping_symbol_position section_start(shndx, 0);
2250   // Find the first mapping symbol record within section shndx.
2251   typename Mapping_symbol_info::const_iterator p =
2252     this->mapping_symbol_info_.lower_bound(section_start);
2253   while (p != this->mapping_symbol_info_.end() &&
2254          p->first.shndx_ == shndx)
2255     {
2256       typename Mapping_symbol_info::const_iterator prev = p;
2257       ++p;
2258       if (prev->second == 'x')
2259         {
2260           section_size_type span_start =
2261             convert_to_section_size_type(prev->first.offset_);
2262           section_size_type span_end;
2263           if (p != this->mapping_symbol_info_.end()
2264               && p->first.shndx_ == shndx)
2265             span_end = convert_to_section_size_type(p->first.offset_);
2266           else
2267             span_end = convert_to_section_size_type(shdr.get_sh_size());
2268
2269           // Here we do not share the scanning code of both errata. For 843419,
2270           // only the last few insns of each page are examined, which is fast,
2271           // whereas, for 835769, every insn pair needs to be checked.
2272
2273           if (parameters->options().fix_cortex_a53_843419())
2274             target->scan_erratum_843419_span(
2275               this, shndx, span_start, span_end,
2276               const_cast<unsigned char*>(input_view), output_address);
2277
2278           if (parameters->options().fix_cortex_a53_835769())
2279             target->scan_erratum_835769_span(
2280               this, shndx, span_start, span_end,
2281               const_cast<unsigned char*>(input_view), output_address);
2282         }
2283     }
2284 }
2285
2286
2287 // Scan relocations for stub generation.
2288
2289 template<int size, bool big_endian>
2290 void
2291 AArch64_relobj<size, big_endian>::scan_sections_for_stubs(
2292     The_target_aarch64* target,
2293     const Symbol_table* symtab,
2294     const Layout* layout)
2295 {
2296   unsigned int shnum = this->shnum();
2297   const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
2298
2299   // Read the section headers.
2300   const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
2301                                                shnum * shdr_size,
2302                                                true, true);
2303
2304   // To speed up processing, we set up hash tables for fast lookup of
2305   // input offsets to output addresses.
2306   this->initialize_input_to_output_maps();
2307
2308   const Relobj::Output_sections& out_sections(this->output_sections());
2309
2310   Relocate_info<size, big_endian> relinfo;
2311   relinfo.symtab = symtab;
2312   relinfo.layout = layout;
2313   relinfo.object = this;
2314
2315   // Do relocation stubs scanning.
2316   const unsigned char* p = pshdrs + shdr_size;
2317   for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
2318     {
2319       const elfcpp::Shdr<size, big_endian> shdr(p);
2320       if (parameters->options().fix_cortex_a53_843419()
2321           || parameters->options().fix_cortex_a53_835769())
2322         scan_errata(i, shdr, out_sections[i], symtab, target);
2323       if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
2324                                                   pshdrs))
2325         {
2326           unsigned int index = this->adjust_shndx(shdr.get_sh_info());
2327           AArch64_address output_offset =
2328               this->get_output_section_offset(index);
2329           AArch64_address output_address;
2330           if (output_offset != invalid_address)
2331             {
2332               output_address = out_sections[index]->address() + output_offset;
2333             }
2334           else
2335             {
2336               // Currently this only happens for a relaxed section.
2337               const Output_relaxed_input_section* poris =
2338                   out_sections[index]->find_relaxed_input_section(this, index);
2339               gold_assert(poris != NULL);
2340               output_address = poris->address();
2341             }
2342
2343           // Get the relocations.
2344           const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
2345                                                         shdr.get_sh_size(),
2346                                                         true, false);
2347
2348           // Get the section contents.
2349           section_size_type input_view_size = 0;
2350           const unsigned char* input_view =
2351               this->section_contents(index, &input_view_size, false);
2352
2353           relinfo.reloc_shndx = i;
2354           relinfo.data_shndx = index;
2355           unsigned int sh_type = shdr.get_sh_type();
2356           unsigned int reloc_size;
2357           gold_assert (sh_type == elfcpp::SHT_RELA);
2358           reloc_size = elfcpp::Elf_sizes<size>::rela_size;
2359
2360           Output_section* os = out_sections[index];
2361           target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
2362                                          shdr.get_sh_size() / reloc_size,
2363                                          os,
2364                                          output_offset == invalid_address,
2365                                          input_view, output_address,
2366                                          input_view_size);
2367         }
2368     }
2369 }
2370
2371
2372 // A class to wrap an ordinary input section containing executable code.
2373
2374 template<int size, bool big_endian>
2375 class AArch64_input_section : public Output_relaxed_input_section
2376 {
2377  public:
2378   typedef Stub_table<size, big_endian> The_stub_table;
2379
2380   AArch64_input_section(Relobj* relobj, unsigned int shndx)
2381     : Output_relaxed_input_section(relobj, shndx, 1),
2382       stub_table_(NULL),
2383       original_contents_(NULL), original_size_(0),
2384       original_addralign_(1)
2385   { }
2386
2387   ~AArch64_input_section()
2388   { delete[] this->original_contents_; }
2389
2390   // Initialize.
2391   void
2392   init();
2393
2394   // Set the stub_table.
2395   void
2396   set_stub_table(The_stub_table* st)
2397   { this->stub_table_ = st; }
2398
2399   // Whether this is a stub table owner.
2400   bool
2401   is_stub_table_owner() const
2402   { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
2403
2404   // Return the original size of the section.
2405   uint32_t
2406   original_size() const
2407   { return this->original_size_; }
2408
2409   // Return the stub table.
2410   The_stub_table*
2411   stub_table()
2412   { return stub_table_; }
2413
2414  protected:
2415   // Write out this input section.
2416   void
2417   do_write(Output_file*);
2418
2419   // Return required alignment of this.
2420   uint64_t
2421   do_addralign() const
2422   {
2423     if (this->is_stub_table_owner())
2424       return std::max(this->stub_table_->addralign(),
2425                       static_cast<uint64_t>(this->original_addralign_));
2426     else
2427       return this->original_addralign_;
2428   }
2429
2430   // Finalize data size.
2431   void
2432   set_final_data_size();
2433
2434   // Reset address and file offset.
2435   void
2436   do_reset_address_and_file_offset();
2437
2438   // Output offset.
2439   bool
2440   do_output_offset(const Relobj* object, unsigned int shndx,
2441                    section_offset_type offset,
2442                    section_offset_type* poutput) const
2443   {
2444     if ((object == this->relobj())
2445         && (shndx == this->shndx())
2446         && (offset >= 0)
2447         && (offset <=
2448             convert_types<section_offset_type, uint32_t>(this->original_size_)))
2449       {
2450         *poutput = offset;
2451         return true;
2452       }
2453     else
2454       return false;
2455   }
2456
2457  private:
2458   // Copying is not allowed.
2459   AArch64_input_section(const AArch64_input_section&);
2460   AArch64_input_section& operator=(const AArch64_input_section&);
2461
2462   // The relocation stubs.
2463   The_stub_table* stub_table_;
2464   // Original section contents.  We have to make a copy here since the file
2465   // containing the original section may not be locked when we need to access
2466   // the contents.
2467   unsigned char* original_contents_;
2468   // Section size of the original input section.
2469   uint32_t original_size_;
2470   // Address alignment of the original input section.
2471   uint32_t original_addralign_;
2472 };  // End of AArch64_input_section
2473
2474
2475 // Finalize data size.
2476
2477 template<int size, bool big_endian>
2478 void
2479 AArch64_input_section<size, big_endian>::set_final_data_size()
2480 {
2481   off_t off = convert_types<off_t, uint64_t>(this->original_size_);
2482
2483   if (this->is_stub_table_owner())
2484     {
2485       this->stub_table_->finalize_data_size();
2486       off = align_address(off, this->stub_table_->addralign());
2487       off += this->stub_table_->data_size();
2488     }
2489   this->set_data_size(off);
2490 }
2491
2492
2493 // Reset address and file offset.
2494
2495 template<int size, bool big_endian>
2496 void
2497 AArch64_input_section<size, big_endian>::do_reset_address_and_file_offset()
2498 {
2499   // Size of the original input section contents.
2500   off_t off = convert_types<off_t, uint64_t>(this->original_size_);
2501
2502   // If this is a stub table owner, account for the stub table size.
2503   if (this->is_stub_table_owner())
2504     {
2505       The_stub_table* stub_table = this->stub_table_;
2506
2507       // Reset the stub table's address and file offset.  The
2508       // current data size for child will be updated after that.
2509       stub_table_->reset_address_and_file_offset();
2510       off = align_address(off, stub_table_->addralign());
2511       off += stub_table->current_data_size();
2512     }
2513
2514   this->set_current_data_size(off);
2515 }
2516
2517
2518 // Initialize an Arm_input_section.
2519
2520 template<int size, bool big_endian>
2521 void
2522 AArch64_input_section<size, big_endian>::init()
2523 {
2524   Relobj* relobj = this->relobj();
2525   unsigned int shndx = this->shndx();
2526
2527   // We have to cache original size, alignment and contents to avoid locking
2528   // the original file.
2529   this->original_addralign_ =
2530       convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
2531
2532   // This is not efficient but we expect only a small number of relaxed
2533   // input sections for stubs.
2534   section_size_type section_size;
2535   const unsigned char* section_contents =
2536       relobj->section_contents(shndx, &section_size, false);
2537   this->original_size_ =
2538       convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
2539
2540   gold_assert(this->original_contents_ == NULL);
2541   this->original_contents_ = new unsigned char[section_size];
2542   memcpy(this->original_contents_, section_contents, section_size);
2543
2544   // We want to make this look like the original input section after
2545   // output sections are finalized.
2546   Output_section* os = relobj->output_section(shndx);
2547   off_t offset = relobj->output_section_offset(shndx);
2548   gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
2549   this->set_address(os->address() + offset);
2550   this->set_file_offset(os->offset() + offset);
2551   this->set_current_data_size(this->original_size_);
2552   this->finalize_data_size();
2553 }
2554
2555
2556 // Write data to output file.
2557
2558 template<int size, bool big_endian>
2559 void
2560 AArch64_input_section<size, big_endian>::do_write(Output_file* of)
2561 {
2562   // We have to write out the original section content.
2563   gold_assert(this->original_contents_ != NULL);
2564   of->write(this->offset(), this->original_contents_,
2565             this->original_size_);
2566
2567   // If this owns a stub table and it is not empty, write it.
2568   if (this->is_stub_table_owner() && !this->stub_table_->empty())
2569     this->stub_table_->write(of);
2570 }
2571
2572
2573 // Arm output section class.  This is defined mainly to add a number of stub
2574 // generation methods.
2575
2576 template<int size, bool big_endian>
2577 class AArch64_output_section : public Output_section
2578 {
2579  public:
2580   typedef Target_aarch64<size, big_endian> The_target_aarch64;
2581   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
2582   typedef Stub_table<size, big_endian> The_stub_table;
2583   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
2584
2585  public:
2586   AArch64_output_section(const char* name, elfcpp::Elf_Word type,
2587                          elfcpp::Elf_Xword flags)
2588     : Output_section(name, type, flags)
2589   { }
2590
2591   ~AArch64_output_section() {}
2592
2593   // Group input sections for stub generation.
2594   void
2595   group_sections(section_size_type, bool, Target_aarch64<size, big_endian>*,
2596                  const Task*);
2597
2598  private:
2599   typedef Output_section::Input_section Input_section;
2600   typedef Output_section::Input_section_list Input_section_list;
2601
2602   // Create a stub group.
2603   void
2604   create_stub_group(Input_section_list::const_iterator,
2605                     Input_section_list::const_iterator,
2606                     Input_section_list::const_iterator,
2607                     The_target_aarch64*,
2608                     std::vector<Output_relaxed_input_section*>&,
2609                     const Task*);
2610 };  // End of AArch64_output_section
2611
2612
2613 // Create a stub group for input sections from FIRST to LAST. OWNER points to
2614 // the input section that will be the owner of the stub table.
2615
2616 template<int size, bool big_endian> void
2617 AArch64_output_section<size, big_endian>::create_stub_group(
2618     Input_section_list::const_iterator first,
2619     Input_section_list::const_iterator last,
2620     Input_section_list::const_iterator owner,
2621     The_target_aarch64* target,
2622     std::vector<Output_relaxed_input_section*>& new_relaxed_sections,
2623     const Task* task)
2624 {
2625   // Currently we convert ordinary input sections into relaxed sections only
2626   // at this point.
2627   The_aarch64_input_section* input_section;
2628   if (owner->is_relaxed_input_section())
2629     gold_unreachable();
2630   else
2631     {
2632       gold_assert(owner->is_input_section());
2633       // Create a new relaxed input section.  We need to lock the original
2634       // file.
2635       Task_lock_obj<Object> tl(task, owner->relobj());
2636       input_section =
2637           target->new_aarch64_input_section(owner->relobj(), owner->shndx());
2638       new_relaxed_sections.push_back(input_section);
2639     }
2640
2641   // Create a stub table.
2642   The_stub_table* stub_table =
2643       target->new_stub_table(input_section);
2644
2645   input_section->set_stub_table(stub_table);
2646
2647   Input_section_list::const_iterator p = first;
2648   // Look for input sections or relaxed input sections in [first ... last].
2649   do
2650     {
2651       if (p->is_input_section() || p->is_relaxed_input_section())
2652         {
2653           // The stub table information for input sections live
2654           // in their objects.
2655           The_aarch64_relobj* aarch64_relobj =
2656               static_cast<The_aarch64_relobj*>(p->relobj());
2657           aarch64_relobj->set_stub_table(p->shndx(), stub_table);
2658         }
2659     }
2660   while (p++ != last);
2661 }
2662
2663
2664 // Group input sections for stub generation. GROUP_SIZE is roughly the limit of
2665 // stub groups. We grow a stub group by adding input section until the size is
2666 // just below GROUP_SIZE. The last input section will be converted into a stub
2667 // table owner. If STUB_ALWAYS_AFTER_BRANCH is false, we also add input sectiond
2668 // after the stub table, effectively doubling the group size.
2669 //
2670 // This is similar to the group_sections() function in elf32-arm.c but is
2671 // implemented differently.
2672
2673 template<int size, bool big_endian>
2674 void AArch64_output_section<size, big_endian>::group_sections(
2675     section_size_type group_size,
2676     bool stubs_always_after_branch,
2677     Target_aarch64<size, big_endian>* target,
2678     const Task* task)
2679 {
2680   typedef enum
2681   {
2682     NO_GROUP,
2683     FINDING_STUB_SECTION,
2684     HAS_STUB_SECTION
2685   } State;
2686
2687   std::vector<Output_relaxed_input_section*> new_relaxed_sections;
2688
2689   State state = NO_GROUP;
2690   section_size_type off = 0;
2691   section_size_type group_begin_offset = 0;
2692   section_size_type group_end_offset = 0;
2693   section_size_type stub_table_end_offset = 0;
2694   Input_section_list::const_iterator group_begin =
2695       this->input_sections().end();
2696   Input_section_list::const_iterator stub_table =
2697       this->input_sections().end();
2698   Input_section_list::const_iterator group_end = this->input_sections().end();
2699   for (Input_section_list::const_iterator p = this->input_sections().begin();
2700        p != this->input_sections().end();
2701        ++p)
2702     {
2703       section_size_type section_begin_offset =
2704         align_address(off, p->addralign());
2705       section_size_type section_end_offset =
2706         section_begin_offset + p->data_size();
2707
2708       // Check to see if we should group the previously seen sections.
2709       switch (state)
2710         {
2711         case NO_GROUP:
2712           break;
2713
2714         case FINDING_STUB_SECTION:
2715           // Adding this section makes the group larger than GROUP_SIZE.
2716           if (section_end_offset - group_begin_offset >= group_size)
2717             {
2718               if (stubs_always_after_branch)
2719                 {
2720                   gold_assert(group_end != this->input_sections().end());
2721                   this->create_stub_group(group_begin, group_end, group_end,
2722                                           target, new_relaxed_sections,
2723                                           task);
2724                   state = NO_GROUP;
2725                 }
2726               else
2727                 {
2728                   // Input sections up to stub_group_size bytes after the stub
2729                   // table can be handled by it too.
2730                   state = HAS_STUB_SECTION;
2731                   stub_table = group_end;
2732                   stub_table_end_offset = group_end_offset;
2733                 }
2734             }
2735             break;
2736
2737         case HAS_STUB_SECTION:
2738           // Adding this section makes the post stub-section group larger
2739           // than GROUP_SIZE.
2740           gold_unreachable();
2741           // NOT SUPPORTED YET. For completeness only.
2742           if (section_end_offset - stub_table_end_offset >= group_size)
2743            {
2744              gold_assert(group_end != this->input_sections().end());
2745              this->create_stub_group(group_begin, group_end, stub_table,
2746                                      target, new_relaxed_sections, task);
2747              state = NO_GROUP;
2748            }
2749            break;
2750
2751           default:
2752             gold_unreachable();
2753         }
2754
2755       // If we see an input section and currently there is no group, start
2756       // a new one.  Skip any empty sections.  We look at the data size
2757       // instead of calling p->relobj()->section_size() to avoid locking.
2758       if ((p->is_input_section() || p->is_relaxed_input_section())
2759           && (p->data_size() != 0))
2760         {
2761           if (state == NO_GROUP)
2762             {
2763               state = FINDING_STUB_SECTION;
2764               group_begin = p;
2765               group_begin_offset = section_begin_offset;
2766             }
2767
2768           // Keep track of the last input section seen.
2769           group_end = p;
2770           group_end_offset = section_end_offset;
2771         }
2772
2773       off = section_end_offset;
2774     }
2775
2776   // Create a stub group for any ungrouped sections.
2777   if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
2778     {
2779       gold_assert(group_end != this->input_sections().end());
2780       this->create_stub_group(group_begin, group_end,
2781                               (state == FINDING_STUB_SECTION
2782                                ? group_end
2783                                : stub_table),
2784                               target, new_relaxed_sections, task);
2785     }
2786
2787   if (!new_relaxed_sections.empty())
2788     this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
2789
2790   // Update the section offsets
2791   for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
2792     {
2793       The_aarch64_relobj* relobj = static_cast<The_aarch64_relobj*>(
2794           new_relaxed_sections[i]->relobj());
2795       unsigned int shndx = new_relaxed_sections[i]->shndx();
2796       // Tell AArch64_relobj that this input section is converted.
2797       relobj->convert_input_section_to_relaxed_section(shndx);
2798     }
2799 }  // End of AArch64_output_section::group_sections
2800
2801
2802 AArch64_reloc_property_table* aarch64_reloc_property_table = NULL;
2803
2804
2805 // The aarch64 target class.
2806 // See the ABI at
2807 // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf
2808 template<int size, bool big_endian>
2809 class Target_aarch64 : public Sized_target<size, big_endian>
2810 {
2811  public:
2812   typedef Target_aarch64<size, big_endian> This;
2813   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
2814       Reloc_section;
2815   typedef Relocate_info<size, big_endian> The_relocate_info;
2816   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
2817   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
2818   typedef Reloc_stub<size, big_endian> The_reloc_stub;
2819   typedef Erratum_stub<size, big_endian> The_erratum_stub;
2820   typedef typename Reloc_stub<size, big_endian>::Key The_reloc_stub_key;
2821   typedef Stub_table<size, big_endian> The_stub_table;
2822   typedef std::vector<The_stub_table*> Stub_table_list;
2823   typedef typename Stub_table_list::iterator Stub_table_iterator;
2824   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
2825   typedef AArch64_output_section<size, big_endian> The_aarch64_output_section;
2826   typedef Unordered_map<Section_id,
2827                         AArch64_input_section<size, big_endian>*,
2828                         Section_id_hash> AArch64_input_section_map;
2829   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
2830   const static int TCB_SIZE = size / 8 * 2;
2831
2832   Target_aarch64(const Target::Target_info* info = &aarch64_info)
2833     : Sized_target<size, big_endian>(info),
2834       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
2835       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
2836       rela_irelative_(NULL), copy_relocs_(elfcpp::R_AARCH64_COPY),
2837       got_mod_index_offset_(-1U),
2838       tlsdesc_reloc_info_(), tls_base_symbol_defined_(false),
2839       stub_tables_(), stub_group_size_(0), aarch64_input_section_map_()
2840   { }
2841
2842   // Scan the relocations to determine unreferenced sections for
2843   // garbage collection.
2844   void
2845   gc_process_relocs(Symbol_table* symtab,
2846                     Layout* layout,
2847                     Sized_relobj_file<size, big_endian>* object,
2848                     unsigned int data_shndx,
2849                     unsigned int sh_type,
2850                     const unsigned char* prelocs,
2851                     size_t reloc_count,
2852                     Output_section* output_section,
2853                     bool needs_special_offset_handling,
2854                     size_t local_symbol_count,
2855                     const unsigned char* plocal_symbols);
2856
2857   // Scan the relocations to look for symbol adjustments.
2858   void
2859   scan_relocs(Symbol_table* symtab,
2860               Layout* layout,
2861               Sized_relobj_file<size, big_endian>* object,
2862               unsigned int data_shndx,
2863               unsigned int sh_type,
2864               const unsigned char* prelocs,
2865               size_t reloc_count,
2866               Output_section* output_section,
2867               bool needs_special_offset_handling,
2868               size_t local_symbol_count,
2869               const unsigned char* plocal_symbols);
2870
2871   // Finalize the sections.
2872   void
2873   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2874
2875   // Return the value to use for a dynamic which requires special
2876   // treatment.
2877   uint64_t
2878   do_dynsym_value(const Symbol*) const;
2879
2880   // Relocate a section.
2881   void
2882   relocate_section(const Relocate_info<size, big_endian>*,
2883                    unsigned int sh_type,
2884                    const unsigned char* prelocs,
2885                    size_t reloc_count,
2886                    Output_section* output_section,
2887                    bool needs_special_offset_handling,
2888                    unsigned char* view,
2889                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
2890                    section_size_type view_size,
2891                    const Reloc_symbol_changes*);
2892
2893   // Scan the relocs during a relocatable link.
2894   void
2895   scan_relocatable_relocs(Symbol_table* symtab,
2896                           Layout* layout,
2897                           Sized_relobj_file<size, big_endian>* object,
2898                           unsigned int data_shndx,
2899                           unsigned int sh_type,
2900                           const unsigned char* prelocs,
2901                           size_t reloc_count,
2902                           Output_section* output_section,
2903                           bool needs_special_offset_handling,
2904                           size_t local_symbol_count,
2905                           const unsigned char* plocal_symbols,
2906                           Relocatable_relocs*);
2907
2908   // Scan the relocs for --emit-relocs.
2909   void
2910   emit_relocs_scan(Symbol_table* symtab,
2911                    Layout* layout,
2912                    Sized_relobj_file<size, big_endian>* object,
2913                    unsigned int data_shndx,
2914                    unsigned int sh_type,
2915                    const unsigned char* prelocs,
2916                    size_t reloc_count,
2917                    Output_section* output_section,
2918                    bool needs_special_offset_handling,
2919                    size_t local_symbol_count,
2920                    const unsigned char* plocal_syms,
2921                    Relocatable_relocs* rr);
2922
2923   // Relocate a section during a relocatable link.
2924   void
2925   relocate_relocs(
2926       const Relocate_info<size, big_endian>*,
2927       unsigned int sh_type,
2928       const unsigned char* prelocs,
2929       size_t reloc_count,
2930       Output_section* output_section,
2931       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
2932       unsigned char* view,
2933       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
2934       section_size_type view_size,
2935       unsigned char* reloc_view,
2936       section_size_type reloc_view_size);
2937
2938   // Return the symbol index to use for a target specific relocation.
2939   // The only target specific relocation is R_AARCH64_TLSDESC for a
2940   // local symbol, which is an absolute reloc.
2941   unsigned int
2942   do_reloc_symbol_index(void*, unsigned int r_type) const
2943   {
2944     gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
2945     return 0;
2946   }
2947
2948   // Return the addend to use for a target specific relocation.
2949   uint64_t
2950   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
2951
2952   // Return the PLT section.
2953   uint64_t
2954   do_plt_address_for_global(const Symbol* gsym) const
2955   { return this->plt_section()->address_for_global(gsym); }
2956
2957   uint64_t
2958   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
2959   { return this->plt_section()->address_for_local(relobj, symndx); }
2960
2961   // This function should be defined in targets that can use relocation
2962   // types to determine (implemented in local_reloc_may_be_function_pointer
2963   // and global_reloc_may_be_function_pointer)
2964   // if a function's pointer is taken.  ICF uses this in safe mode to only
2965   // fold those functions whose pointer is defintely not taken.
2966   bool
2967   do_can_check_for_function_pointers() const
2968   { return true; }
2969
2970   // Return the number of entries in the PLT.
2971   unsigned int
2972   plt_entry_count() const;
2973
2974   //Return the offset of the first non-reserved PLT entry.
2975   unsigned int
2976   first_plt_entry_offset() const;
2977
2978   // Return the size of each PLT entry.
2979   unsigned int
2980   plt_entry_size() const;
2981
2982   // Create a stub table.
2983   The_stub_table*
2984   new_stub_table(The_aarch64_input_section*);
2985
2986   // Create an aarch64 input section.
2987   The_aarch64_input_section*
2988   new_aarch64_input_section(Relobj*, unsigned int);
2989
2990   // Find an aarch64 input section instance for a given OBJ and SHNDX.
2991   The_aarch64_input_section*
2992   find_aarch64_input_section(Relobj*, unsigned int) const;
2993
2994   // Return the thread control block size.
2995   unsigned int
2996   tcb_size() const { return This::TCB_SIZE; }
2997
2998   // Scan a section for stub generation.
2999   void
3000   scan_section_for_stubs(const Relocate_info<size, big_endian>*, unsigned int,
3001                          const unsigned char*, size_t, Output_section*,
3002                          bool, const unsigned char*,
3003                          Address,
3004                          section_size_type);
3005
3006   // Scan a relocation section for stub.
3007   template<int sh_type>
3008   void
3009   scan_reloc_section_for_stubs(
3010       const The_relocate_info* relinfo,
3011       const unsigned char* prelocs,
3012       size_t reloc_count,
3013       Output_section* output_section,
3014       bool needs_special_offset_handling,
3015       const unsigned char* view,
3016       Address view_address,
3017       section_size_type);
3018
3019   // Relocate a single stub.
3020   void
3021   relocate_stub(The_reloc_stub*, const Relocate_info<size, big_endian>*,
3022                 Output_section*, unsigned char*, Address,
3023                 section_size_type);
3024
3025   // Get the default AArch64 target.
3026   static This*
3027   current_target()
3028   {
3029     gold_assert(parameters->target().machine_code() == elfcpp::EM_AARCH64
3030                 && parameters->target().get_size() == size
3031                 && parameters->target().is_big_endian() == big_endian);
3032     return static_cast<This*>(parameters->sized_target<size, big_endian>());
3033   }
3034
3035
3036   // Scan erratum 843419 for a part of a section.
3037   void
3038   scan_erratum_843419_span(
3039     AArch64_relobj<size, big_endian>*,
3040     unsigned int,
3041     const section_size_type,
3042     const section_size_type,
3043     unsigned char*,
3044     Address);
3045
3046   // Scan erratum 835769 for a part of a section.
3047   void
3048   scan_erratum_835769_span(
3049     AArch64_relobj<size, big_endian>*,
3050     unsigned int,
3051     const section_size_type,
3052     const section_size_type,
3053     unsigned char*,
3054     Address);
3055
3056  protected:
3057   void
3058   do_select_as_default_target()
3059   {
3060     gold_assert(aarch64_reloc_property_table == NULL);
3061     aarch64_reloc_property_table = new AArch64_reloc_property_table();
3062   }
3063
3064   // Add a new reloc argument, returning the index in the vector.
3065   size_t
3066   add_tlsdesc_info(Sized_relobj_file<size, big_endian>* object,
3067                    unsigned int r_sym)
3068   {
3069     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
3070     return this->tlsdesc_reloc_info_.size() - 1;
3071   }
3072
3073   virtual Output_data_plt_aarch64<size, big_endian>*
3074   do_make_data_plt(Layout* layout,
3075                    Output_data_got_aarch64<size, big_endian>* got,
3076                    Output_data_space* got_plt,
3077                    Output_data_space* got_irelative)
3078   {
3079     return new Output_data_plt_aarch64_standard<size, big_endian>(
3080       layout, got, got_plt, got_irelative);
3081   }
3082
3083
3084   // do_make_elf_object to override the same function in the base class.
3085   Object*
3086   do_make_elf_object(const std::string&, Input_file*, off_t,
3087                      const elfcpp::Ehdr<size, big_endian>&);
3088
3089   Output_data_plt_aarch64<size, big_endian>*
3090   make_data_plt(Layout* layout,
3091                 Output_data_got_aarch64<size, big_endian>* got,
3092                 Output_data_space* got_plt,
3093                 Output_data_space* got_irelative)
3094   {
3095     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
3096   }
3097
3098   // We only need to generate stubs, and hence perform relaxation if we are
3099   // not doing relocatable linking.
3100   virtual bool
3101   do_may_relax() const
3102   { return !parameters->options().relocatable(); }
3103
3104   // Relaxation hook.  This is where we do stub generation.
3105   virtual bool
3106   do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*);
3107
3108   void
3109   group_sections(Layout* layout,
3110                  section_size_type group_size,
3111                  bool stubs_always_after_branch,
3112                  const Task* task);
3113
3114   void
3115   scan_reloc_for_stub(const The_relocate_info*, unsigned int,
3116                       const Sized_symbol<size>*, unsigned int,
3117                       const Symbol_value<size>*,
3118                       typename elfcpp::Elf_types<size>::Elf_Swxword,
3119                       Address Elf_Addr);
3120
3121   // Make an output section.
3122   Output_section*
3123   do_make_output_section(const char* name, elfcpp::Elf_Word type,
3124                          elfcpp::Elf_Xword flags)
3125   { return new The_aarch64_output_section(name, type, flags); }
3126
3127  private:
3128   // The class which scans relocations.
3129   class Scan
3130   {
3131   public:
3132     Scan()
3133       : issued_non_pic_error_(false)
3134     { }
3135
3136     inline void
3137     local(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
3138           Sized_relobj_file<size, big_endian>* object,
3139           unsigned int data_shndx,
3140           Output_section* output_section,
3141           const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
3142           const elfcpp::Sym<size, big_endian>& lsym,
3143           bool is_discarded);
3144
3145     inline void
3146     global(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
3147            Sized_relobj_file<size, big_endian>* object,
3148            unsigned int data_shndx,
3149            Output_section* output_section,
3150            const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
3151            Symbol* gsym);
3152
3153     inline bool
3154     local_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
3155                                         Target_aarch64<size, big_endian>* ,
3156                                         Sized_relobj_file<size, big_endian>* ,
3157                                         unsigned int ,
3158                                         Output_section* ,
3159                                         const elfcpp::Rela<size, big_endian>& ,
3160                                         unsigned int r_type,
3161                                         const elfcpp::Sym<size, big_endian>&);
3162
3163     inline bool
3164     global_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
3165                                          Target_aarch64<size, big_endian>* ,
3166                                          Sized_relobj_file<size, big_endian>* ,
3167                                          unsigned int ,
3168                                          Output_section* ,
3169                                          const elfcpp::Rela<size, big_endian>& ,
3170                                          unsigned int r_type,
3171                                          Symbol* gsym);
3172
3173   private:
3174     static void
3175     unsupported_reloc_local(Sized_relobj_file<size, big_endian>*,
3176                             unsigned int r_type);
3177
3178     static void
3179     unsupported_reloc_global(Sized_relobj_file<size, big_endian>*,
3180                              unsigned int r_type, Symbol*);
3181
3182     inline bool
3183     possible_function_pointer_reloc(unsigned int r_type);
3184
3185     void
3186     check_non_pic(Relobj*, unsigned int r_type);
3187
3188     bool
3189     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, big_endian>*,
3190                               unsigned int r_type);
3191
3192     // Whether we have issued an error about a non-PIC compilation.
3193     bool issued_non_pic_error_;
3194   };
3195
3196   // The class which implements relocation.
3197   class Relocate
3198   {
3199    public:
3200     Relocate()
3201       : skip_call_tls_get_addr_(false)
3202     { }
3203
3204     ~Relocate()
3205     { }
3206
3207     // Do a relocation.  Return false if the caller should not issue
3208     // any warnings about this relocation.
3209     inline bool
3210     relocate(const Relocate_info<size, big_endian>*, unsigned int,
3211              Target_aarch64*, Output_section*, size_t, const unsigned char*,
3212              const Sized_symbol<size>*, const Symbol_value<size>*,
3213              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
3214              section_size_type);
3215
3216   private:
3217     inline typename AArch64_relocate_functions<size, big_endian>::Status
3218     relocate_tls(const Relocate_info<size, big_endian>*,
3219                  Target_aarch64<size, big_endian>*,
3220                  size_t,
3221                  const elfcpp::Rela<size, big_endian>&,
3222                  unsigned int r_type, const Sized_symbol<size>*,
3223                  const Symbol_value<size>*,
3224                  unsigned char*,
3225                  typename elfcpp::Elf_types<size>::Elf_Addr);
3226
3227     inline typename AArch64_relocate_functions<size, big_endian>::Status
3228     tls_gd_to_le(
3229                  const Relocate_info<size, big_endian>*,
3230                  Target_aarch64<size, big_endian>*,
3231                  const elfcpp::Rela<size, big_endian>&,
3232                  unsigned int,
3233                  unsigned char*,
3234                  const Symbol_value<size>*);
3235
3236     inline typename AArch64_relocate_functions<size, big_endian>::Status
3237     tls_ld_to_le(
3238                  const Relocate_info<size, big_endian>*,
3239                  Target_aarch64<size, big_endian>*,
3240                  const elfcpp::Rela<size, big_endian>&,
3241                  unsigned int,
3242                  unsigned char*,
3243                  const Symbol_value<size>*);
3244
3245     inline typename AArch64_relocate_functions<size, big_endian>::Status
3246     tls_ie_to_le(
3247                  const Relocate_info<size, big_endian>*,
3248                  Target_aarch64<size, big_endian>*,
3249                  const elfcpp::Rela<size, big_endian>&,
3250                  unsigned int,
3251                  unsigned char*,
3252                  const Symbol_value<size>*);
3253
3254     inline typename AArch64_relocate_functions<size, big_endian>::Status
3255     tls_desc_gd_to_le(
3256                  const Relocate_info<size, big_endian>*,
3257                  Target_aarch64<size, big_endian>*,
3258                  const elfcpp::Rela<size, big_endian>&,
3259                  unsigned int,
3260                  unsigned char*,
3261                  const Symbol_value<size>*);
3262
3263     inline typename AArch64_relocate_functions<size, big_endian>::Status
3264     tls_desc_gd_to_ie(
3265                  const Relocate_info<size, big_endian>*,
3266                  Target_aarch64<size, big_endian>*,
3267                  const elfcpp::Rela<size, big_endian>&,
3268                  unsigned int,
3269                  unsigned char*,
3270                  const Symbol_value<size>*,
3271                  typename elfcpp::Elf_types<size>::Elf_Addr,
3272                  typename elfcpp::Elf_types<size>::Elf_Addr);
3273
3274     bool skip_call_tls_get_addr_;
3275
3276   };  // End of class Relocate
3277
3278   // Adjust TLS relocation type based on the options and whether this
3279   // is a local symbol.
3280   static tls::Tls_optimization
3281   optimize_tls_reloc(bool is_final, int r_type);
3282
3283   // Get the GOT section, creating it if necessary.
3284   Output_data_got_aarch64<size, big_endian>*
3285   got_section(Symbol_table*, Layout*);
3286
3287   // Get the GOT PLT section.
3288   Output_data_space*
3289   got_plt_section() const
3290   {
3291     gold_assert(this->got_plt_ != NULL);
3292     return this->got_plt_;
3293   }
3294
3295   // Get the GOT section for TLSDESC entries.
3296   Output_data_got<size, big_endian>*
3297   got_tlsdesc_section() const
3298   {
3299     gold_assert(this->got_tlsdesc_ != NULL);
3300     return this->got_tlsdesc_;
3301   }
3302
3303   // Create the PLT section.
3304   void
3305   make_plt_section(Symbol_table* symtab, Layout* layout);
3306
3307   // Create a PLT entry for a global symbol.
3308   void
3309   make_plt_entry(Symbol_table*, Layout*, Symbol*);
3310
3311   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
3312   void
3313   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
3314                              Sized_relobj_file<size, big_endian>* relobj,
3315                              unsigned int local_sym_index);
3316
3317   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
3318   void
3319   define_tls_base_symbol(Symbol_table*, Layout*);
3320
3321   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
3322   void
3323   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
3324
3325   // Create a GOT entry for the TLS module index.
3326   unsigned int
3327   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
3328                       Sized_relobj_file<size, big_endian>* object);
3329
3330   // Get the PLT section.
3331   Output_data_plt_aarch64<size, big_endian>*
3332   plt_section() const
3333   {
3334     gold_assert(this->plt_ != NULL);
3335     return this->plt_;
3336   }
3337
3338   // Helper method to create erratum stubs for ST_E_843419 and ST_E_835769. For
3339   // ST_E_843419, we need an additional field for adrp offset.
3340   void create_erratum_stub(
3341     AArch64_relobj<size, big_endian>* relobj,
3342     unsigned int shndx,
3343     section_size_type erratum_insn_offset,
3344     Address erratum_address,
3345     typename Insn_utilities::Insntype erratum_insn,
3346     int erratum_type,
3347     unsigned int e843419_adrp_offset=0);
3348
3349   // Return whether this is a 3-insn erratum sequence.
3350   bool is_erratum_843419_sequence(
3351       typename elfcpp::Swap<32,big_endian>::Valtype insn1,
3352       typename elfcpp::Swap<32,big_endian>::Valtype insn2,
3353       typename elfcpp::Swap<32,big_endian>::Valtype insn3);
3354
3355   // Return whether this is a 835769 sequence.
3356   // (Similarly implemented as in elfnn-aarch64.c.)
3357   bool is_erratum_835769_sequence(
3358       typename elfcpp::Swap<32,big_endian>::Valtype,
3359       typename elfcpp::Swap<32,big_endian>::Valtype);
3360
3361   // Get the dynamic reloc section, creating it if necessary.
3362   Reloc_section*
3363   rela_dyn_section(Layout*);
3364
3365   // Get the section to use for TLSDESC relocations.
3366   Reloc_section*
3367   rela_tlsdesc_section(Layout*) const;
3368
3369   // Get the section to use for IRELATIVE relocations.
3370   Reloc_section*
3371   rela_irelative_section(Layout*);
3372
3373   // Add a potential copy relocation.
3374   void
3375   copy_reloc(Symbol_table* symtab, Layout* layout,
3376              Sized_relobj_file<size, big_endian>* object,
3377              unsigned int shndx, Output_section* output_section,
3378              Symbol* sym, const elfcpp::Rela<size, big_endian>& reloc)
3379   {
3380     unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
3381     this->copy_relocs_.copy_reloc(symtab, layout,
3382                                   symtab->get_sized_symbol<size>(sym),
3383                                   object, shndx, output_section,
3384                                   r_type, reloc.get_r_offset(),
3385                                   reloc.get_r_addend(),
3386                                   this->rela_dyn_section(layout));
3387   }
3388
3389   // Information about this specific target which we pass to the
3390   // general Target structure.
3391   static const Target::Target_info aarch64_info;
3392
3393   // The types of GOT entries needed for this platform.
3394   // These values are exposed to the ABI in an incremental link.
3395   // Do not renumber existing values without changing the version
3396   // number of the .gnu_incremental_inputs section.
3397   enum Got_type
3398   {
3399     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
3400     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
3401     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
3402     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
3403   };
3404
3405   // This type is used as the argument to the target specific
3406   // relocation routines.  The only target specific reloc is
3407   // R_AARCh64_TLSDESC against a local symbol.
3408   struct Tlsdesc_info
3409   {
3410     Tlsdesc_info(Sized_relobj_file<size, big_endian>* a_object,
3411                  unsigned int a_r_sym)
3412       : object(a_object), r_sym(a_r_sym)
3413     { }
3414
3415     // The object in which the local symbol is defined.
3416     Sized_relobj_file<size, big_endian>* object;
3417     // The local symbol index in the object.
3418     unsigned int r_sym;
3419   };
3420
3421   // The GOT section.
3422   Output_data_got_aarch64<size, big_endian>* got_;
3423   // The PLT section.
3424   Output_data_plt_aarch64<size, big_endian>* plt_;
3425   // The GOT PLT section.
3426   Output_data_space* got_plt_;
3427   // The GOT section for IRELATIVE relocations.
3428   Output_data_space* got_irelative_;
3429   // The GOT section for TLSDESC relocations.
3430   Output_data_got<size, big_endian>* got_tlsdesc_;
3431   // The _GLOBAL_OFFSET_TABLE_ symbol.
3432   Symbol* global_offset_table_;
3433   // The dynamic reloc section.
3434   Reloc_section* rela_dyn_;
3435   // The section to use for IRELATIVE relocs.
3436   Reloc_section* rela_irelative_;
3437   // Relocs saved to avoid a COPY reloc.
3438   Copy_relocs<elfcpp::SHT_RELA, size, big_endian> copy_relocs_;
3439   // Offset of the GOT entry for the TLS module index.
3440   unsigned int got_mod_index_offset_;
3441   // We handle R_AARCH64_TLSDESC against a local symbol as a target
3442   // specific relocation. Here we store the object and local symbol
3443   // index for the relocation.
3444   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
3445   // True if the _TLS_MODULE_BASE_ symbol has been defined.
3446   bool tls_base_symbol_defined_;
3447   // List of stub_tables
3448   Stub_table_list stub_tables_;
3449   // Actual stub group size
3450   section_size_type stub_group_size_;
3451   AArch64_input_section_map aarch64_input_section_map_;
3452 };  // End of Target_aarch64
3453
3454
3455 template<>
3456 const Target::Target_info Target_aarch64<64, false>::aarch64_info =
3457 {
3458   64,                   // size
3459   false,                // is_big_endian
3460   elfcpp::EM_AARCH64,   // machine_code
3461   false,                // has_make_symbol
3462   false,                // has_resolve
3463   false,                // has_code_fill
3464   true,                 // is_default_stack_executable
3465   true,                 // can_icf_inline_merge_sections
3466   '\0',                 // wrap_char
3467   "/lib/ld.so.1",       // program interpreter
3468   0x400000,             // default_text_segment_address
3469   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3470   0x1000,               // common_pagesize (overridable by -z common-page-size)
3471   false,                // isolate_execinstr
3472   0,                    // rosegment_gap
3473   elfcpp::SHN_UNDEF,    // small_common_shndx
3474   elfcpp::SHN_UNDEF,    // large_common_shndx
3475   0,                    // small_common_section_flags
3476   0,                    // large_common_section_flags
3477   NULL,                 // attributes_section
3478   NULL,                 // attributes_vendor
3479   "_start",             // entry_symbol_name
3480   32,                   // hash_entry_size
3481 };
3482
3483 template<>
3484 const Target::Target_info Target_aarch64<32, false>::aarch64_info =
3485 {
3486   32,                   // size
3487   false,                // is_big_endian
3488   elfcpp::EM_AARCH64,   // machine_code
3489   false,                // has_make_symbol
3490   false,                // has_resolve
3491   false,                // has_code_fill
3492   true,                 // is_default_stack_executable
3493   false,                // can_icf_inline_merge_sections
3494   '\0',                 // wrap_char
3495   "/lib/ld.so.1",       // program interpreter
3496   0x400000,             // default_text_segment_address
3497   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3498   0x1000,               // common_pagesize (overridable by -z common-page-size)
3499   false,                // isolate_execinstr
3500   0,                    // rosegment_gap
3501   elfcpp::SHN_UNDEF,    // small_common_shndx
3502   elfcpp::SHN_UNDEF,    // large_common_shndx
3503   0,                    // small_common_section_flags
3504   0,                    // large_common_section_flags
3505   NULL,                 // attributes_section
3506   NULL,                 // attributes_vendor
3507   "_start",             // entry_symbol_name
3508   32,                   // hash_entry_size
3509 };
3510
3511 template<>
3512 const Target::Target_info Target_aarch64<64, true>::aarch64_info =
3513 {
3514   64,                   // size
3515   true,                 // is_big_endian
3516   elfcpp::EM_AARCH64,   // machine_code
3517   false,                // has_make_symbol
3518   false,                // has_resolve
3519   false,                // has_code_fill
3520   true,                 // is_default_stack_executable
3521   true,                 // can_icf_inline_merge_sections
3522   '\0',                 // wrap_char
3523   "/lib/ld.so.1",       // program interpreter
3524   0x400000,             // default_text_segment_address
3525   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3526   0x1000,               // common_pagesize (overridable by -z common-page-size)
3527   false,                // isolate_execinstr
3528   0,                    // rosegment_gap
3529   elfcpp::SHN_UNDEF,    // small_common_shndx
3530   elfcpp::SHN_UNDEF,    // large_common_shndx
3531   0,                    // small_common_section_flags
3532   0,                    // large_common_section_flags
3533   NULL,                 // attributes_section
3534   NULL,                 // attributes_vendor
3535   "_start",             // entry_symbol_name
3536   32,                   // hash_entry_size
3537 };
3538
3539 template<>
3540 const Target::Target_info Target_aarch64<32, true>::aarch64_info =
3541 {
3542   32,                   // size
3543   true,                 // is_big_endian
3544   elfcpp::EM_AARCH64,   // machine_code
3545   false,                // has_make_symbol
3546   false,                // has_resolve
3547   false,                // has_code_fill
3548   true,                 // is_default_stack_executable
3549   false,                // can_icf_inline_merge_sections
3550   '\0',                 // wrap_char
3551   "/lib/ld.so.1",       // program interpreter
3552   0x400000,             // default_text_segment_address
3553   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3554   0x1000,               // common_pagesize (overridable by -z common-page-size)
3555   false,                // isolate_execinstr
3556   0,                    // rosegment_gap
3557   elfcpp::SHN_UNDEF,    // small_common_shndx
3558   elfcpp::SHN_UNDEF,    // large_common_shndx
3559   0,                    // small_common_section_flags
3560   0,                    // large_common_section_flags
3561   NULL,                 // attributes_section
3562   NULL,                 // attributes_vendor
3563   "_start",             // entry_symbol_name
3564   32,                   // hash_entry_size
3565 };
3566
3567 // Get the GOT section, creating it if necessary.
3568
3569 template<int size, bool big_endian>
3570 Output_data_got_aarch64<size, big_endian>*
3571 Target_aarch64<size, big_endian>::got_section(Symbol_table* symtab,
3572                                               Layout* layout)
3573 {
3574   if (this->got_ == NULL)
3575     {
3576       gold_assert(symtab != NULL && layout != NULL);
3577
3578       // When using -z now, we can treat .got.plt as a relro section.
3579       // Without -z now, it is modified after program startup by lazy
3580       // PLT relocations.
3581       bool is_got_plt_relro = parameters->options().now();
3582       Output_section_order got_order = (is_got_plt_relro
3583                                         ? ORDER_RELRO
3584                                         : ORDER_RELRO_LAST);
3585       Output_section_order got_plt_order = (is_got_plt_relro
3586                                             ? ORDER_RELRO
3587                                             : ORDER_NON_RELRO_FIRST);
3588
3589       // Layout of .got and .got.plt sections.
3590       // .got[0] &_DYNAMIC                          <-_GLOBAL_OFFSET_TABLE_
3591       // ...
3592       // .gotplt[0] reserved for ld.so (&linkmap)   <--DT_PLTGOT
3593       // .gotplt[1] reserved for ld.so (resolver)
3594       // .gotplt[2] reserved
3595
3596       // Generate .got section.
3597       this->got_ = new Output_data_got_aarch64<size, big_endian>(symtab,
3598                                                                  layout);
3599       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3600                                       (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
3601                                       this->got_, got_order, true);
3602       // The first word of GOT is reserved for the address of .dynamic.
3603       // We put 0 here now. The value will be replaced later in
3604       // Output_data_got_aarch64::do_write.
3605       this->got_->add_constant(0);
3606
3607       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3608       // _GLOBAL_OFFSET_TABLE_ value points to the start of the .got section,
3609       // even if there is a .got.plt section.
3610       this->global_offset_table_ =
3611         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
3612                                       Symbol_table::PREDEFINED,
3613                                       this->got_,
3614                                       0, 0, elfcpp::STT_OBJECT,
3615                                       elfcpp::STB_LOCAL,
3616                                       elfcpp::STV_HIDDEN, 0,
3617                                       false, false);
3618
3619       // Generate .got.plt section.
3620       this->got_plt_ = new Output_data_space(size / 8, "** GOT PLT");
3621       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3622                                       (elfcpp::SHF_ALLOC
3623                                        | elfcpp::SHF_WRITE),
3624                                       this->got_plt_, got_plt_order,
3625                                       is_got_plt_relro);
3626
3627       // The first three entries are reserved.
3628       this->got_plt_->set_current_data_size(
3629         AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
3630
3631       // If there are any IRELATIVE relocations, they get GOT entries
3632       // in .got.plt after the jump slot entries.
3633       this->got_irelative_ = new Output_data_space(size / 8,
3634                                                    "** GOT IRELATIVE PLT");
3635       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3636                                       (elfcpp::SHF_ALLOC
3637                                        | elfcpp::SHF_WRITE),
3638                                       this->got_irelative_,
3639                                       got_plt_order,
3640                                       is_got_plt_relro);
3641
3642       // If there are any TLSDESC relocations, they get GOT entries in
3643       // .got.plt after the jump slot and IRELATIVE entries.
3644       this->got_tlsdesc_ = new Output_data_got<size, big_endian>();
3645       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3646                                       (elfcpp::SHF_ALLOC
3647                                        | elfcpp::SHF_WRITE),
3648                                       this->got_tlsdesc_,
3649                                       got_plt_order,
3650                                       is_got_plt_relro);
3651
3652       if (!is_got_plt_relro)
3653         {
3654           // Those bytes can go into the relro segment.
3655           layout->increase_relro(
3656             AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
3657         }
3658
3659     }
3660   return this->got_;
3661 }
3662
3663 // Get the dynamic reloc section, creating it if necessary.
3664
3665 template<int size, bool big_endian>
3666 typename Target_aarch64<size, big_endian>::Reloc_section*
3667 Target_aarch64<size, big_endian>::rela_dyn_section(Layout* layout)
3668 {
3669   if (this->rela_dyn_ == NULL)
3670     {
3671       gold_assert(layout != NULL);
3672       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
3673       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
3674                                       elfcpp::SHF_ALLOC, this->rela_dyn_,
3675                                       ORDER_DYNAMIC_RELOCS, false);
3676     }
3677   return this->rela_dyn_;
3678 }
3679
3680 // Get the section to use for IRELATIVE relocs, creating it if
3681 // necessary.  These go in .rela.dyn, but only after all other dynamic
3682 // relocations.  They need to follow the other dynamic relocations so
3683 // that they can refer to global variables initialized by those
3684 // relocs.
3685
3686 template<int size, bool big_endian>
3687 typename Target_aarch64<size, big_endian>::Reloc_section*
3688 Target_aarch64<size, big_endian>::rela_irelative_section(Layout* layout)
3689 {
3690   if (this->rela_irelative_ == NULL)
3691     {
3692       // Make sure we have already created the dynamic reloc section.
3693       this->rela_dyn_section(layout);
3694       this->rela_irelative_ = new Reloc_section(false);
3695       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
3696                                       elfcpp::SHF_ALLOC, this->rela_irelative_,
3697                                       ORDER_DYNAMIC_RELOCS, false);
3698       gold_assert(this->rela_dyn_->output_section()
3699                   == this->rela_irelative_->output_section());
3700     }
3701   return this->rela_irelative_;
3702 }
3703
3704
3705 // do_make_elf_object to override the same function in the base class.  We need
3706 // to use a target-specific sub-class of Sized_relobj_file<size, big_endian> to
3707 // store backend specific information. Hence we need to have our own ELF object
3708 // creation.
3709
3710 template<int size, bool big_endian>
3711 Object*
3712 Target_aarch64<size, big_endian>::do_make_elf_object(
3713     const std::string& name,
3714     Input_file* input_file,
3715     off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
3716 {
3717   int et = ehdr.get_e_type();
3718   // ET_EXEC files are valid input for --just-symbols/-R,
3719   // and we treat them as relocatable objects.
3720   if (et == elfcpp::ET_EXEC && input_file->just_symbols())
3721     return Sized_target<size, big_endian>::do_make_elf_object(
3722         name, input_file, offset, ehdr);
3723   else if (et == elfcpp::ET_REL)
3724     {
3725       AArch64_relobj<size, big_endian>* obj =
3726         new AArch64_relobj<size, big_endian>(name, input_file, offset, ehdr);
3727       obj->setup();
3728       return obj;
3729     }
3730   else if (et == elfcpp::ET_DYN)
3731     {
3732       // Keep base implementation.
3733       Sized_dynobj<size, big_endian>* obj =
3734           new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
3735       obj->setup();
3736       return obj;
3737     }
3738   else
3739     {
3740       gold_error(_("%s: unsupported ELF file type %d"),
3741                  name.c_str(), et);
3742       return NULL;
3743     }
3744 }
3745
3746
3747 // Scan a relocation for stub generation.
3748
3749 template<int size, bool big_endian>
3750 void
3751 Target_aarch64<size, big_endian>::scan_reloc_for_stub(
3752     const Relocate_info<size, big_endian>* relinfo,
3753     unsigned int r_type,
3754     const Sized_symbol<size>* gsym,
3755     unsigned int r_sym,
3756     const Symbol_value<size>* psymval,
3757     typename elfcpp::Elf_types<size>::Elf_Swxword addend,
3758     Address address)
3759 {
3760   const AArch64_relobj<size, big_endian>* aarch64_relobj =
3761       static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
3762
3763   Symbol_value<size> symval;
3764   if (gsym != NULL)
3765     {
3766       const AArch64_reloc_property* arp = aarch64_reloc_property_table->
3767         get_reloc_property(r_type);
3768       if (gsym->use_plt_offset(arp->reference_flags()))
3769         {
3770           // This uses a PLT, change the symbol value.
3771           symval.set_output_value(this->plt_section()->address()
3772                                   + gsym->plt_offset());
3773           psymval = &symval;
3774         }
3775       else if (gsym->is_undefined())
3776         {
3777           // There is no need to generate a stub symbol if the original symbol
3778           // is undefined.
3779           gold_debug(DEBUG_TARGET,
3780                      "stub: not creating a stub for undefined symbol %s in file %s",
3781                      gsym->name(), aarch64_relobj->name().c_str());
3782           return;
3783         }
3784     }
3785
3786   // Get the symbol value.
3787   typename Symbol_value<size>::Value value = psymval->value(aarch64_relobj, 0);
3788
3789   // Owing to pipelining, the PC relative branches below actually skip
3790   // two instructions when the branch offset is 0.
3791   Address destination = static_cast<Address>(-1);
3792   switch (r_type)
3793     {
3794     case elfcpp::R_AARCH64_CALL26:
3795     case elfcpp::R_AARCH64_JUMP26:
3796       destination = value + addend;
3797       break;
3798     default:
3799       gold_unreachable();
3800     }
3801
3802   int stub_type = The_reloc_stub::
3803       stub_type_for_reloc(r_type, address, destination);
3804   if (stub_type == ST_NONE)
3805     return;
3806
3807   The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
3808   gold_assert(stub_table != NULL);
3809
3810   The_reloc_stub_key key(stub_type, gsym, aarch64_relobj, r_sym, addend);
3811   The_reloc_stub* stub = stub_table->find_reloc_stub(key);
3812   if (stub == NULL)
3813     {
3814       stub = new The_reloc_stub(stub_type);
3815       stub_table->add_reloc_stub(stub, key);
3816     }
3817   stub->set_destination_address(destination);
3818 }  // End of Target_aarch64::scan_reloc_for_stub
3819
3820
3821 // This function scans a relocation section for stub generation.
3822 // The template parameter Relocate must be a class type which provides
3823 // a single function, relocate(), which implements the machine
3824 // specific part of a relocation.
3825
3826 // BIG_ENDIAN is the endianness of the data.  SH_TYPE is the section type:
3827 // SHT_REL or SHT_RELA.
3828
3829 // PRELOCS points to the relocation data.  RELOC_COUNT is the number
3830 // of relocs.  OUTPUT_SECTION is the output section.
3831 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
3832 // mapped to output offsets.
3833
3834 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
3835 // VIEW_SIZE is the size.  These refer to the input section, unless
3836 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
3837 // the output section.
3838
3839 template<int size, bool big_endian>
3840 template<int sh_type>
3841 void inline
3842 Target_aarch64<size, big_endian>::scan_reloc_section_for_stubs(
3843     const Relocate_info<size, big_endian>* relinfo,
3844     const unsigned char* prelocs,
3845     size_t reloc_count,
3846     Output_section* /*output_section*/,
3847     bool /*needs_special_offset_handling*/,
3848     const unsigned char* /*view*/,
3849     Address view_address,
3850     section_size_type)
3851 {
3852   typedef typename Reloc_types<sh_type,size,big_endian>::Reloc Reltype;
3853
3854   const int reloc_size =
3855       Reloc_types<sh_type,size,big_endian>::reloc_size;
3856   AArch64_relobj<size, big_endian>* object =
3857       static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
3858   unsigned int local_count = object->local_symbol_count();
3859
3860   gold::Default_comdat_behavior default_comdat_behavior;
3861   Comdat_behavior comdat_behavior = CB_UNDETERMINED;
3862
3863   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
3864     {
3865       Reltype reloc(prelocs);
3866       typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
3867       unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
3868       unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
3869       if (r_type != elfcpp::R_AARCH64_CALL26
3870           && r_type != elfcpp::R_AARCH64_JUMP26)
3871         continue;
3872
3873       section_offset_type offset =
3874           convert_to_section_size_type(reloc.get_r_offset());
3875
3876       // Get the addend.
3877       typename elfcpp::Elf_types<size>::Elf_Swxword addend =
3878           reloc.get_r_addend();
3879
3880       const Sized_symbol<size>* sym;
3881       Symbol_value<size> symval;
3882       const Symbol_value<size> *psymval;
3883       bool is_defined_in_discarded_section;
3884       unsigned int shndx;
3885       if (r_sym < local_count)
3886         {
3887           sym = NULL;
3888           psymval = object->local_symbol(r_sym);
3889
3890           // If the local symbol belongs to a section we are discarding,
3891           // and that section is a debug section, try to find the
3892           // corresponding kept section and map this symbol to its
3893           // counterpart in the kept section.  The symbol must not
3894           // correspond to a section we are folding.
3895           bool is_ordinary;
3896           shndx = psymval->input_shndx(&is_ordinary);
3897           is_defined_in_discarded_section =
3898             (is_ordinary
3899              && shndx != elfcpp::SHN_UNDEF
3900              && !object->is_section_included(shndx)
3901              && !relinfo->symtab->is_section_folded(object, shndx));
3902
3903           // We need to compute the would-be final value of this local
3904           // symbol.
3905           if (!is_defined_in_discarded_section)
3906             {
3907               typedef Sized_relobj_file<size, big_endian> ObjType;
3908               if (psymval->is_section_symbol())
3909                 symval.set_is_section_symbol();
3910               typename ObjType::Compute_final_local_value_status status =
3911                 object->compute_final_local_value(r_sym, psymval, &symval,
3912                                                   relinfo->symtab);
3913               if (status == ObjType::CFLV_OK)
3914                 {
3915                   // Currently we cannot handle a branch to a target in
3916                   // a merged section.  If this is the case, issue an error
3917                   // and also free the merge symbol value.
3918                   if (!symval.has_output_value())
3919                     {
3920                       const std::string& section_name =
3921                         object->section_name(shndx);
3922                       object->error(_("cannot handle branch to local %u "
3923                                           "in a merged section %s"),
3924                                         r_sym, section_name.c_str());
3925                     }
3926                   psymval = &symval;
3927                 }
3928               else
3929                 {
3930                   // We cannot determine the final value.
3931                   continue;
3932                 }
3933             }
3934         }
3935       else
3936         {
3937           const Symbol* gsym;
3938           gsym = object->global_symbol(r_sym);
3939           gold_assert(gsym != NULL);
3940           if (gsym->is_forwarder())
3941             gsym = relinfo->symtab->resolve_forwards(gsym);
3942
3943           sym = static_cast<const Sized_symbol<size>*>(gsym);
3944           if (sym->has_symtab_index() && sym->symtab_index() != -1U)
3945             symval.set_output_symtab_index(sym->symtab_index());
3946           else
3947             symval.set_no_output_symtab_entry();
3948
3949           // We need to compute the would-be final value of this global
3950           // symbol.
3951           const Symbol_table* symtab = relinfo->symtab;
3952           const Sized_symbol<size>* sized_symbol =
3953               symtab->get_sized_symbol<size>(gsym);
3954           Symbol_table::Compute_final_value_status status;
3955           typename elfcpp::Elf_types<size>::Elf_Addr value =
3956               symtab->compute_final_value<size>(sized_symbol, &status);
3957
3958           // Skip this if the symbol has not output section.
3959           if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
3960             continue;
3961           symval.set_output_value(value);
3962
3963           if (gsym->type() == elfcpp::STT_TLS)
3964             symval.set_is_tls_symbol();
3965           else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
3966             symval.set_is_ifunc_symbol();
3967           psymval = &symval;
3968
3969           is_defined_in_discarded_section =
3970               (gsym->is_defined_in_discarded_section()
3971                && gsym->is_undefined());
3972           shndx = 0;
3973         }
3974
3975       Symbol_value<size> symval2;
3976       if (is_defined_in_discarded_section)
3977         {
3978           if (comdat_behavior == CB_UNDETERMINED)
3979             {
3980               std::string name = object->section_name(relinfo->data_shndx);
3981               comdat_behavior = default_comdat_behavior.get(name.c_str());
3982             }
3983           if (comdat_behavior == CB_PRETEND)
3984             {
3985               bool found;
3986               typename elfcpp::Elf_types<size>::Elf_Addr value =
3987                 object->map_to_kept_section(shndx, &found);
3988               if (found)
3989                 symval2.set_output_value(value + psymval->input_value());
3990               else
3991                 symval2.set_output_value(0);
3992             }
3993           else
3994             {
3995               if (comdat_behavior == CB_WARNING)
3996                 gold_warning_at_location(relinfo, i, offset,
3997                                          _("relocation refers to discarded "
3998                                            "section"));
3999               symval2.set_output_value(0);
4000             }
4001           symval2.set_no_output_symtab_entry();
4002           psymval = &symval2;
4003         }
4004
4005       // If symbol is a section symbol, we don't know the actual type of
4006       // destination.  Give up.
4007       if (psymval->is_section_symbol())
4008         continue;
4009
4010       this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
4011                                 addend, view_address + offset);
4012     }  // End of iterating relocs in a section
4013 }  // End of Target_aarch64::scan_reloc_section_for_stubs
4014
4015
4016 // Scan an input section for stub generation.
4017
4018 template<int size, bool big_endian>
4019 void
4020 Target_aarch64<size, big_endian>::scan_section_for_stubs(
4021     const Relocate_info<size, big_endian>* relinfo,
4022     unsigned int sh_type,
4023     const unsigned char* prelocs,
4024     size_t reloc_count,
4025     Output_section* output_section,
4026     bool needs_special_offset_handling,
4027     const unsigned char* view,
4028     Address view_address,
4029     section_size_type view_size)
4030 {
4031   gold_assert(sh_type == elfcpp::SHT_RELA);
4032   this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
4033       relinfo,
4034       prelocs,
4035       reloc_count,
4036       output_section,
4037       needs_special_offset_handling,
4038       view,
4039       view_address,
4040       view_size);
4041 }
4042
4043
4044 // Relocate a single stub.
4045
4046 template<int size, bool big_endian>
4047 void Target_aarch64<size, big_endian>::
4048 relocate_stub(The_reloc_stub* stub,
4049               const The_relocate_info*,
4050               Output_section*,
4051               unsigned char* view,
4052               Address address,
4053               section_size_type)
4054 {
4055   typedef AArch64_relocate_functions<size, big_endian> The_reloc_functions;
4056   typedef typename The_reloc_functions::Status The_reloc_functions_status;
4057   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
4058
4059   Insntype* ip = reinterpret_cast<Insntype*>(view);
4060   int insn_number = stub->insn_num();
4061   const uint32_t* insns = stub->insns();
4062   // Check the insns are really those stub insns.
4063   for (int i = 0; i < insn_number; ++i)
4064     {
4065       Insntype insn = elfcpp::Swap<32,big_endian>::readval(ip + i);
4066       gold_assert(((uint32_t)insn == insns[i]));
4067     }
4068
4069   Address dest = stub->destination_address();
4070
4071   switch(stub->type())
4072     {
4073     case ST_ADRP_BRANCH:
4074       {
4075         // 1st reloc is ADR_PREL_PG_HI21
4076         The_reloc_functions_status status =
4077             The_reloc_functions::adrp(view, dest, address);
4078         // An error should never arise in the above step. If so, please
4079         // check 'aarch64_valid_for_adrp_p'.
4080         gold_assert(status == The_reloc_functions::STATUS_OKAY);
4081
4082         // 2nd reloc is ADD_ABS_LO12_NC
4083         const AArch64_reloc_property* arp =
4084             aarch64_reloc_property_table->get_reloc_property(
4085                 elfcpp::R_AARCH64_ADD_ABS_LO12_NC);
4086         gold_assert(arp != NULL);
4087         status = The_reloc_functions::template
4088             rela_general<32>(view + 4, dest, 0, arp);
4089         // An error should never arise, it is an "_NC" relocation.
4090         gold_assert(status == The_reloc_functions::STATUS_OKAY);
4091       }
4092       break;
4093
4094     case ST_LONG_BRANCH_ABS:
4095       // 1st reloc is R_AARCH64_PREL64, at offset 8
4096       elfcpp::Swap<64,big_endian>::writeval(view + 8, dest);
4097       break;
4098
4099     case ST_LONG_BRANCH_PCREL:
4100       {
4101         // "PC" calculation is the 2nd insn in the stub.
4102         uint64_t offset = dest - (address + 4);
4103         // Offset is placed at offset 4 and 5.
4104         elfcpp::Swap<64,big_endian>::writeval(view + 16, offset);
4105       }
4106       break;
4107
4108     default:
4109       gold_unreachable();
4110     }
4111 }
4112
4113
4114 // A class to handle the PLT data.
4115 // This is an abstract base class that handles most of the linker details
4116 // but does not know the actual contents of PLT entries.  The derived
4117 // classes below fill in those details.
4118
4119 template<int size, bool big_endian>
4120 class Output_data_plt_aarch64 : public Output_section_data
4121 {
4122  public:
4123   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
4124       Reloc_section;
4125   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
4126
4127   Output_data_plt_aarch64(Layout* layout,
4128                           uint64_t addralign,
4129                           Output_data_got_aarch64<size, big_endian>* got,
4130                           Output_data_space* got_plt,
4131                           Output_data_space* got_irelative)
4132     : Output_section_data(addralign), tlsdesc_rel_(NULL), irelative_rel_(NULL),
4133       got_(got), got_plt_(got_plt), got_irelative_(got_irelative),
4134       count_(0), irelative_count_(0), tlsdesc_got_offset_(-1U)
4135   { this->init(layout); }
4136
4137   // Initialize the PLT section.
4138   void
4139   init(Layout* layout);
4140
4141   // Add an entry to the PLT.
4142   void
4143   add_entry(Symbol_table*, Layout*, Symbol* gsym);
4144
4145   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
4146   unsigned int
4147   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
4148                         Sized_relobj_file<size, big_endian>* relobj,
4149                         unsigned int local_sym_index);
4150
4151   // Add the relocation for a PLT entry.
4152   void
4153   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
4154                  unsigned int got_offset);
4155
4156   // Add the reserved TLSDESC_PLT entry to the PLT.
4157   void
4158   reserve_tlsdesc_entry(unsigned int got_offset)
4159   { this->tlsdesc_got_offset_ = got_offset; }
4160
4161   // Return true if a TLSDESC_PLT entry has been reserved.
4162   bool
4163   has_tlsdesc_entry() const
4164   { return this->tlsdesc_got_offset_ != -1U; }
4165
4166   // Return the GOT offset for the reserved TLSDESC_PLT entry.
4167   unsigned int
4168   get_tlsdesc_got_offset() const
4169   { return this->tlsdesc_got_offset_; }
4170
4171   // Return the PLT offset of the reserved TLSDESC_PLT entry.
4172   unsigned int
4173   get_tlsdesc_plt_offset() const
4174   {
4175     return (this->first_plt_entry_offset() +
4176             (this->count_ + this->irelative_count_)
4177             * this->get_plt_entry_size());
4178   }
4179
4180   // Return the .rela.plt section data.
4181   Reloc_section*
4182   rela_plt()
4183   { return this->rel_; }
4184
4185   // Return where the TLSDESC relocations should go.
4186   Reloc_section*
4187   rela_tlsdesc(Layout*);
4188
4189   // Return where the IRELATIVE relocations should go in the PLT
4190   // relocations.
4191   Reloc_section*
4192   rela_irelative(Symbol_table*, Layout*);
4193
4194   // Return whether we created a section for IRELATIVE relocations.
4195   bool
4196   has_irelative_section() const
4197   { return this->irelative_rel_ != NULL; }
4198
4199   // Return the number of PLT entries.
4200   unsigned int
4201   entry_count() const
4202   { return this->count_ + this->irelative_count_; }
4203
4204   // Return the offset of the first non-reserved PLT entry.
4205   unsigned int
4206   first_plt_entry_offset() const
4207   { return this->do_first_plt_entry_offset(); }
4208
4209   // Return the size of a PLT entry.
4210   unsigned int
4211   get_plt_entry_size() const
4212   { return this->do_get_plt_entry_size(); }
4213
4214   // Return the reserved tlsdesc entry size.
4215   unsigned int
4216   get_plt_tlsdesc_entry_size() const
4217   { return this->do_get_plt_tlsdesc_entry_size(); }
4218
4219   // Return the PLT address to use for a global symbol.
4220   uint64_t
4221   address_for_global(const Symbol*);
4222
4223   // Return the PLT address to use for a local symbol.
4224   uint64_t
4225   address_for_local(const Relobj*, unsigned int symndx);
4226
4227  protected:
4228   // Fill in the first PLT entry.
4229   void
4230   fill_first_plt_entry(unsigned char* pov,
4231                        Address got_address,
4232                        Address plt_address)
4233   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
4234
4235   // Fill in a normal PLT entry.
4236   void
4237   fill_plt_entry(unsigned char* pov,
4238                  Address got_address,
4239                  Address plt_address,
4240                  unsigned int got_offset,
4241                  unsigned int plt_offset)
4242   {
4243     this->do_fill_plt_entry(pov, got_address, plt_address,
4244                             got_offset, plt_offset);
4245   }
4246
4247   // Fill in the reserved TLSDESC PLT entry.
4248   void
4249   fill_tlsdesc_entry(unsigned char* pov,
4250                      Address gotplt_address,
4251                      Address plt_address,
4252                      Address got_base,
4253                      unsigned int tlsdesc_got_offset,
4254                      unsigned int plt_offset)
4255   {
4256     this->do_fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
4257                                 tlsdesc_got_offset, plt_offset);
4258   }
4259
4260   virtual unsigned int
4261   do_first_plt_entry_offset() const = 0;
4262
4263   virtual unsigned int
4264   do_get_plt_entry_size() const = 0;
4265
4266   virtual unsigned int
4267   do_get_plt_tlsdesc_entry_size() const = 0;
4268
4269   virtual void
4270   do_fill_first_plt_entry(unsigned char* pov,
4271                           Address got_addr,
4272                           Address plt_addr) = 0;
4273
4274   virtual void
4275   do_fill_plt_entry(unsigned char* pov,
4276                     Address got_address,
4277                     Address plt_address,
4278                     unsigned int got_offset,
4279                     unsigned int plt_offset) = 0;
4280
4281   virtual void
4282   do_fill_tlsdesc_entry(unsigned char* pov,
4283                         Address gotplt_address,
4284                         Address plt_address,
4285                         Address got_base,
4286                         unsigned int tlsdesc_got_offset,
4287                         unsigned int plt_offset) = 0;
4288
4289   void
4290   do_adjust_output_section(Output_section* os);
4291
4292   // Write to a map file.
4293   void
4294   do_print_to_mapfile(Mapfile* mapfile) const
4295   { mapfile->print_output_data(this, _("** PLT")); }
4296
4297  private:
4298   // Set the final size.
4299   void
4300   set_final_data_size();
4301
4302   // Write out the PLT data.
4303   void
4304   do_write(Output_file*);
4305
4306   // The reloc section.
4307   Reloc_section* rel_;
4308
4309   // The TLSDESC relocs, if necessary.  These must follow the regular
4310   // PLT relocs.
4311   Reloc_section* tlsdesc_rel_;
4312
4313   // The IRELATIVE relocs, if necessary.  These must follow the
4314   // regular PLT relocations.
4315   Reloc_section* irelative_rel_;
4316
4317   // The .got section.
4318   Output_data_got_aarch64<size, big_endian>* got_;
4319
4320   // The .got.plt section.
4321   Output_data_space* got_plt_;
4322
4323   // The part of the .got.plt section used for IRELATIVE relocs.
4324   Output_data_space* got_irelative_;
4325
4326   // The number of PLT entries.
4327   unsigned int count_;
4328
4329   // Number of PLT entries with R_AARCH64_IRELATIVE relocs.  These
4330   // follow the regular PLT entries.
4331   unsigned int irelative_count_;
4332
4333   // GOT offset of the reserved TLSDESC_GOT entry for the lazy trampoline.
4334   // Communicated to the loader via DT_TLSDESC_GOT. The magic value -1
4335   // indicates an offset is not allocated.
4336   unsigned int tlsdesc_got_offset_;
4337 };
4338
4339 // Initialize the PLT section.
4340
4341 template<int size, bool big_endian>
4342 void
4343 Output_data_plt_aarch64<size, big_endian>::init(Layout* layout)
4344 {
4345   this->rel_ = new Reloc_section(false);
4346   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4347                                   elfcpp::SHF_ALLOC, this->rel_,
4348                                   ORDER_DYNAMIC_PLT_RELOCS, false);
4349 }
4350
4351 template<int size, bool big_endian>
4352 void
4353 Output_data_plt_aarch64<size, big_endian>::do_adjust_output_section(
4354     Output_section* os)
4355 {
4356   os->set_entsize(this->get_plt_entry_size());
4357 }
4358
4359 // Add an entry to the PLT.
4360
4361 template<int size, bool big_endian>
4362 void
4363 Output_data_plt_aarch64<size, big_endian>::add_entry(Symbol_table* symtab,
4364     Layout* layout, Symbol* gsym)
4365 {
4366   gold_assert(!gsym->has_plt_offset());
4367
4368   unsigned int* pcount;
4369   unsigned int plt_reserved;
4370   Output_section_data_build* got;
4371
4372   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4373       && gsym->can_use_relative_reloc(false))
4374     {
4375       pcount = &this->irelative_count_;
4376       plt_reserved = 0;
4377       got = this->got_irelative_;
4378     }
4379   else
4380     {
4381       pcount = &this->count_;
4382       plt_reserved = this->first_plt_entry_offset();
4383       got = this->got_plt_;
4384     }
4385
4386   gsym->set_plt_offset((*pcount) * this->get_plt_entry_size()
4387                        + plt_reserved);
4388
4389   ++*pcount;
4390
4391   section_offset_type got_offset = got->current_data_size();
4392
4393   // Every PLT entry needs a GOT entry which points back to the PLT
4394   // entry (this will be changed by the dynamic linker, normally
4395   // lazily when the function is called).
4396   got->set_current_data_size(got_offset + size / 8);
4397
4398   // Every PLT entry needs a reloc.
4399   this->add_relocation(symtab, layout, gsym, got_offset);
4400
4401   // Note that we don't need to save the symbol. The contents of the
4402   // PLT are independent of which symbols are used. The symbols only
4403   // appear in the relocations.
4404 }
4405
4406 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
4407 // the PLT offset.
4408
4409 template<int size, bool big_endian>
4410 unsigned int
4411 Output_data_plt_aarch64<size, big_endian>::add_local_ifunc_entry(
4412     Symbol_table* symtab,
4413     Layout* layout,
4414     Sized_relobj_file<size, big_endian>* relobj,
4415     unsigned int local_sym_index)
4416 {
4417   unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
4418   ++this->irelative_count_;
4419
4420   section_offset_type got_offset = this->got_irelative_->current_data_size();
4421
4422   // Every PLT entry needs a GOT entry which points back to the PLT
4423   // entry.
4424   this->got_irelative_->set_current_data_size(got_offset + size / 8);
4425
4426   // Every PLT entry needs a reloc.
4427   Reloc_section* rela = this->rela_irelative(symtab, layout);
4428   rela->add_symbolless_local_addend(relobj, local_sym_index,
4429                                     elfcpp::R_AARCH64_IRELATIVE,
4430                                     this->got_irelative_, got_offset, 0);
4431
4432   return plt_offset;
4433 }
4434
4435 // Add the relocation for a PLT entry.
4436
4437 template<int size, bool big_endian>
4438 void
4439 Output_data_plt_aarch64<size, big_endian>::add_relocation(
4440     Symbol_table* symtab, Layout* layout, Symbol* gsym, unsigned int got_offset)
4441 {
4442   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4443       && gsym->can_use_relative_reloc(false))
4444     {
4445       Reloc_section* rela = this->rela_irelative(symtab, layout);
4446       rela->add_symbolless_global_addend(gsym, elfcpp::R_AARCH64_IRELATIVE,
4447                                          this->got_irelative_, got_offset, 0);
4448     }
4449   else
4450     {
4451       gsym->set_needs_dynsym_entry();
4452       this->rel_->add_global(gsym, elfcpp::R_AARCH64_JUMP_SLOT, this->got_plt_,
4453                              got_offset, 0);
4454     }
4455 }
4456
4457 // Return where the TLSDESC relocations should go, creating it if
4458 // necessary.  These follow the JUMP_SLOT relocations.
4459
4460 template<int size, bool big_endian>
4461 typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
4462 Output_data_plt_aarch64<size, big_endian>::rela_tlsdesc(Layout* layout)
4463 {
4464   if (this->tlsdesc_rel_ == NULL)
4465     {
4466       this->tlsdesc_rel_ = new Reloc_section(false);
4467       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4468                                       elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
4469                                       ORDER_DYNAMIC_PLT_RELOCS, false);
4470       gold_assert(this->tlsdesc_rel_->output_section()
4471                   == this->rel_->output_section());
4472     }
4473   return this->tlsdesc_rel_;
4474 }
4475
4476 // Return where the IRELATIVE relocations should go in the PLT.  These
4477 // follow the JUMP_SLOT and the TLSDESC relocations.
4478
4479 template<int size, bool big_endian>
4480 typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
4481 Output_data_plt_aarch64<size, big_endian>::rela_irelative(Symbol_table* symtab,
4482                                                           Layout* layout)
4483 {
4484   if (this->irelative_rel_ == NULL)
4485     {
4486       // Make sure we have a place for the TLSDESC relocations, in
4487       // case we see any later on.
4488       this->rela_tlsdesc(layout);
4489       this->irelative_rel_ = new Reloc_section(false);
4490       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4491                                       elfcpp::SHF_ALLOC, this->irelative_rel_,
4492                                       ORDER_DYNAMIC_PLT_RELOCS, false);
4493       gold_assert(this->irelative_rel_->output_section()
4494                   == this->rel_->output_section());
4495
4496       if (parameters->doing_static_link())
4497         {
4498           // A statically linked executable will only have a .rela.plt
4499           // section to hold R_AARCH64_IRELATIVE relocs for
4500           // STT_GNU_IFUNC symbols.  The library will use these
4501           // symbols to locate the IRELATIVE relocs at program startup
4502           // time.
4503           symtab->define_in_output_data("__rela_iplt_start", NULL,
4504                                         Symbol_table::PREDEFINED,
4505                                         this->irelative_rel_, 0, 0,
4506                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
4507                                         elfcpp::STV_HIDDEN, 0, false, true);
4508           symtab->define_in_output_data("__rela_iplt_end", NULL,
4509                                         Symbol_table::PREDEFINED,
4510                                         this->irelative_rel_, 0, 0,
4511                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
4512                                         elfcpp::STV_HIDDEN, 0, true, true);
4513         }
4514     }
4515   return this->irelative_rel_;
4516 }
4517
4518 // Return the PLT address to use for a global symbol.
4519
4520 template<int size, bool big_endian>
4521 uint64_t
4522 Output_data_plt_aarch64<size, big_endian>::address_for_global(
4523   const Symbol* gsym)
4524 {
4525   uint64_t offset = 0;
4526   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4527       && gsym->can_use_relative_reloc(false))
4528     offset = (this->first_plt_entry_offset() +
4529               this->count_ * this->get_plt_entry_size());
4530   return this->address() + offset + gsym->plt_offset();
4531 }
4532
4533 // Return the PLT address to use for a local symbol.  These are always
4534 // IRELATIVE relocs.
4535
4536 template<int size, bool big_endian>
4537 uint64_t
4538 Output_data_plt_aarch64<size, big_endian>::address_for_local(
4539     const Relobj* object,
4540     unsigned int r_sym)
4541 {
4542   return (this->address()
4543           + this->first_plt_entry_offset()
4544           + this->count_ * this->get_plt_entry_size()
4545           + object->local_plt_offset(r_sym));
4546 }
4547
4548 // Set the final size.
4549
4550 template<int size, bool big_endian>
4551 void
4552 Output_data_plt_aarch64<size, big_endian>::set_final_data_size()
4553 {
4554   unsigned int count = this->count_ + this->irelative_count_;
4555   unsigned int extra_size = 0;
4556   if (this->has_tlsdesc_entry())
4557     extra_size += this->get_plt_tlsdesc_entry_size();
4558   this->set_data_size(this->first_plt_entry_offset()
4559                       + count * this->get_plt_entry_size()
4560                       + extra_size);
4561 }
4562
4563 template<int size, bool big_endian>
4564 class Output_data_plt_aarch64_standard :
4565   public Output_data_plt_aarch64<size, big_endian>
4566 {
4567  public:
4568   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
4569   Output_data_plt_aarch64_standard(
4570       Layout* layout,
4571       Output_data_got_aarch64<size, big_endian>* got,
4572       Output_data_space* got_plt,
4573       Output_data_space* got_irelative)
4574     : Output_data_plt_aarch64<size, big_endian>(layout,
4575                                                 size == 32 ? 4 : 8,
4576                                                 got, got_plt,
4577                                                 got_irelative)
4578   { }
4579
4580  protected:
4581   // Return the offset of the first non-reserved PLT entry.
4582   virtual unsigned int
4583   do_first_plt_entry_offset() const
4584   { return this->first_plt_entry_size; }
4585
4586   // Return the size of a PLT entry
4587   virtual unsigned int
4588   do_get_plt_entry_size() const
4589   { return this->plt_entry_size; }
4590
4591   // Return the size of a tlsdesc entry
4592   virtual unsigned int
4593   do_get_plt_tlsdesc_entry_size() const
4594   { return this->plt_tlsdesc_entry_size; }
4595
4596   virtual void
4597   do_fill_first_plt_entry(unsigned char* pov,
4598                           Address got_address,
4599                           Address plt_address);
4600
4601   virtual void
4602   do_fill_plt_entry(unsigned char* pov,
4603                     Address got_address,
4604                     Address plt_address,
4605                     unsigned int got_offset,
4606                     unsigned int plt_offset);
4607
4608   virtual void
4609   do_fill_tlsdesc_entry(unsigned char* pov,
4610                         Address gotplt_address,
4611                         Address plt_address,
4612                         Address got_base,
4613                         unsigned int tlsdesc_got_offset,
4614                         unsigned int plt_offset);
4615
4616  private:
4617   // The size of the first plt entry size.
4618   static const int first_plt_entry_size = 32;
4619   // The size of the plt entry size.
4620   static const int plt_entry_size = 16;
4621   // The size of the plt tlsdesc entry size.
4622   static const int plt_tlsdesc_entry_size = 32;
4623   // Template for the first PLT entry.
4624   static const uint32_t first_plt_entry[first_plt_entry_size / 4];
4625   // Template for subsequent PLT entries.
4626   static const uint32_t plt_entry[plt_entry_size / 4];
4627   // The reserved TLSDESC entry in the PLT for an executable.
4628   static const uint32_t tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4];
4629 };
4630
4631 // The first entry in the PLT for an executable.
4632
4633 template<>
4634 const uint32_t
4635 Output_data_plt_aarch64_standard<32, false>::
4636     first_plt_entry[first_plt_entry_size / 4] =
4637 {
4638   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4639   0x90000010,   /* adrp x16, PLT_GOT+0x8  */
4640   0xb9400A11,   /* ldr w17, [x16, #PLT_GOT+0x8]  */
4641   0x11002210,   /* add w16, w16,#PLT_GOT+0x8   */
4642   0xd61f0220,   /* br x17  */
4643   0xd503201f,   /* nop */
4644   0xd503201f,   /* nop */
4645   0xd503201f,   /* nop */
4646 };
4647
4648
4649 template<>
4650 const uint32_t
4651 Output_data_plt_aarch64_standard<32, true>::
4652     first_plt_entry[first_plt_entry_size / 4] =
4653 {
4654   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4655   0x90000010,   /* adrp x16, PLT_GOT+0x8  */
4656   0xb9400A11,   /* ldr w17, [x16, #PLT_GOT+0x8]  */
4657   0x11002210,   /* add w16, w16,#PLT_GOT+0x8   */
4658   0xd61f0220,   /* br x17  */
4659   0xd503201f,   /* nop */
4660   0xd503201f,   /* nop */
4661   0xd503201f,   /* nop */
4662 };
4663
4664
4665 template<>
4666 const uint32_t
4667 Output_data_plt_aarch64_standard<64, false>::
4668     first_plt_entry[first_plt_entry_size / 4] =
4669 {
4670   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4671   0x90000010,   /* adrp x16, PLT_GOT+16  */
4672   0xf9400A11,   /* ldr x17, [x16, #PLT_GOT+0x10]  */
4673   0x91004210,   /* add x16, x16,#PLT_GOT+0x10   */
4674   0xd61f0220,   /* br x17  */
4675   0xd503201f,   /* nop */
4676   0xd503201f,   /* nop */
4677   0xd503201f,   /* nop */
4678 };
4679
4680
4681 template<>
4682 const uint32_t
4683 Output_data_plt_aarch64_standard<64, true>::
4684     first_plt_entry[first_plt_entry_size / 4] =
4685 {
4686   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4687   0x90000010,   /* adrp x16, PLT_GOT+16  */
4688   0xf9400A11,   /* ldr x17, [x16, #PLT_GOT+0x10]  */
4689   0x91004210,   /* add x16, x16,#PLT_GOT+0x10   */
4690   0xd61f0220,   /* br x17  */
4691   0xd503201f,   /* nop */
4692   0xd503201f,   /* nop */
4693   0xd503201f,   /* nop */
4694 };
4695
4696
4697 template<>
4698 const uint32_t
4699 Output_data_plt_aarch64_standard<32, false>::
4700     plt_entry[plt_entry_size / 4] =
4701 {
4702   0x90000010,   /* adrp x16, PLTGOT + n * 4  */
4703   0xb9400211,   /* ldr w17, [w16, PLTGOT + n * 4] */
4704   0x11000210,   /* add w16, w16, :lo12:PLTGOT + n * 4  */
4705   0xd61f0220,   /* br x17.  */
4706 };
4707
4708
4709 template<>
4710 const uint32_t
4711 Output_data_plt_aarch64_standard<32, true>::
4712     plt_entry[plt_entry_size / 4] =
4713 {
4714   0x90000010,   /* adrp x16, PLTGOT + n * 4  */
4715   0xb9400211,   /* ldr w17, [w16, PLTGOT + n * 4] */
4716   0x11000210,   /* add w16, w16, :lo12:PLTGOT + n * 4  */
4717   0xd61f0220,   /* br x17.  */
4718 };
4719
4720
4721 template<>
4722 const uint32_t
4723 Output_data_plt_aarch64_standard<64, false>::
4724     plt_entry[plt_entry_size / 4] =
4725 {
4726   0x90000010,   /* adrp x16, PLTGOT + n * 8  */
4727   0xf9400211,   /* ldr x17, [x16, PLTGOT + n * 8] */
4728   0x91000210,   /* add x16, x16, :lo12:PLTGOT + n * 8  */
4729   0xd61f0220,   /* br x17.  */
4730 };
4731
4732
4733 template<>
4734 const uint32_t
4735 Output_data_plt_aarch64_standard<64, true>::
4736     plt_entry[plt_entry_size / 4] =
4737 {
4738   0x90000010,   /* adrp x16, PLTGOT + n * 8  */
4739   0xf9400211,   /* ldr x17, [x16, PLTGOT + n * 8] */
4740   0x91000210,   /* add x16, x16, :lo12:PLTGOT + n * 8  */
4741   0xd61f0220,   /* br x17.  */
4742 };
4743
4744
4745 template<int size, bool big_endian>
4746 void
4747 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_first_plt_entry(
4748     unsigned char* pov,
4749     Address got_address,
4750     Address plt_address)
4751 {
4752   // PLT0 of the small PLT looks like this in ELF64 -
4753   // stp x16, x30, [sp, #-16]!          Save the reloc and lr on stack.
4754   // adrp x16, PLT_GOT + 16             Get the page base of the GOTPLT
4755   // ldr  x17, [x16, #:lo12:PLT_GOT+16] Load the address of the
4756   //                                    symbol resolver
4757   // add  x16, x16, #:lo12:PLT_GOT+16   Load the lo12 bits of the
4758   //                                    GOTPLT entry for this.
4759   // br   x17
4760   // PLT0 will be slightly different in ELF32 due to different got entry
4761   // size.
4762   memcpy(pov, this->first_plt_entry, this->first_plt_entry_size);
4763   Address gotplt_2nd_ent = got_address + (size / 8) * 2;
4764
4765   // Fill in the top 21 bits for this: ADRP x16, PLT_GOT + 8 * 2.
4766   // ADRP:  (PG(S+A)-PG(P)) >> 12) & 0x1fffff.
4767   // FIXME: This only works for 64bit
4768   AArch64_relocate_functions<size, big_endian>::adrp(pov + 4,
4769       gotplt_2nd_ent, plt_address + 4);
4770
4771   // Fill in R_AARCH64_LDST8_LO12
4772   elfcpp::Swap<32, big_endian>::writeval(
4773       pov + 8,
4774       ((this->first_plt_entry[2] & 0xffc003ff)
4775        | ((gotplt_2nd_ent & 0xff8) << 7)));
4776
4777   // Fill in R_AARCH64_ADD_ABS_LO12
4778   elfcpp::Swap<32, big_endian>::writeval(
4779       pov + 12,
4780       ((this->first_plt_entry[3] & 0xffc003ff)
4781        | ((gotplt_2nd_ent & 0xfff) << 10)));
4782 }
4783
4784
4785 // Subsequent entries in the PLT for an executable.
4786 // FIXME: This only works for 64bit
4787
4788 template<int size, bool big_endian>
4789 void
4790 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_plt_entry(
4791     unsigned char* pov,
4792     Address got_address,
4793     Address plt_address,
4794     unsigned int got_offset,
4795     unsigned int plt_offset)
4796 {
4797   memcpy(pov, this->plt_entry, this->plt_entry_size);
4798
4799   Address gotplt_entry_address = got_address + got_offset;
4800   Address plt_entry_address = plt_address + plt_offset;
4801
4802   // Fill in R_AARCH64_PCREL_ADR_HI21
4803   AArch64_relocate_functions<size, big_endian>::adrp(
4804       pov,
4805       gotplt_entry_address,
4806       plt_entry_address);
4807
4808   // Fill in R_AARCH64_LDST64_ABS_LO12
4809   elfcpp::Swap<32, big_endian>::writeval(
4810       pov + 4,
4811       ((this->plt_entry[1] & 0xffc003ff)
4812        | ((gotplt_entry_address & 0xff8) << 7)));
4813
4814   // Fill in R_AARCH64_ADD_ABS_LO12
4815   elfcpp::Swap<32, big_endian>::writeval(
4816       pov + 8,
4817       ((this->plt_entry[2] & 0xffc003ff)
4818        | ((gotplt_entry_address & 0xfff) <<10)));
4819
4820 }
4821
4822
4823 template<>
4824 const uint32_t
4825 Output_data_plt_aarch64_standard<32, false>::
4826     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4827 {
4828   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4829   0x90000002,   /* adrp x2, 0 */
4830   0x90000003,   /* adrp x3, 0 */
4831   0xb9400042,   /* ldr w2, [w2, #0] */
4832   0x11000063,   /* add w3, w3, 0 */
4833   0xd61f0040,   /* br x2 */
4834   0xd503201f,   /* nop */
4835   0xd503201f,   /* nop */
4836 };
4837
4838 template<>
4839 const uint32_t
4840 Output_data_plt_aarch64_standard<32, true>::
4841     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4842 {
4843   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4844   0x90000002,   /* adrp x2, 0 */
4845   0x90000003,   /* adrp x3, 0 */
4846   0xb9400042,   /* ldr w2, [w2, #0] */
4847   0x11000063,   /* add w3, w3, 0 */
4848   0xd61f0040,   /* br x2 */
4849   0xd503201f,   /* nop */
4850   0xd503201f,   /* nop */
4851 };
4852
4853 template<>
4854 const uint32_t
4855 Output_data_plt_aarch64_standard<64, false>::
4856     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4857 {
4858   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4859   0x90000002,   /* adrp x2, 0 */
4860   0x90000003,   /* adrp x3, 0 */
4861   0xf9400042,   /* ldr x2, [x2, #0] */
4862   0x91000063,   /* add x3, x3, 0 */
4863   0xd61f0040,   /* br x2 */
4864   0xd503201f,   /* nop */
4865   0xd503201f,   /* nop */
4866 };
4867
4868 template<>
4869 const uint32_t
4870 Output_data_plt_aarch64_standard<64, true>::
4871     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4872 {
4873   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4874   0x90000002,   /* adrp x2, 0 */
4875   0x90000003,   /* adrp x3, 0 */
4876   0xf9400042,   /* ldr x2, [x2, #0] */
4877   0x91000063,   /* add x3, x3, 0 */
4878   0xd61f0040,   /* br x2 */
4879   0xd503201f,   /* nop */
4880   0xd503201f,   /* nop */
4881 };
4882
4883 template<int size, bool big_endian>
4884 void
4885 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_tlsdesc_entry(
4886     unsigned char* pov,
4887     Address gotplt_address,
4888     Address plt_address,
4889     Address got_base,
4890     unsigned int tlsdesc_got_offset,
4891     unsigned int plt_offset)
4892 {
4893   memcpy(pov, tlsdesc_plt_entry, plt_tlsdesc_entry_size);
4894
4895   // move DT_TLSDESC_GOT address into x2
4896   // move .got.plt address into x3
4897   Address tlsdesc_got_entry = got_base + tlsdesc_got_offset;
4898   Address plt_entry_address = plt_address + plt_offset;
4899
4900   // R_AARCH64_ADR_PREL_PG_HI21
4901   AArch64_relocate_functions<size, big_endian>::adrp(
4902       pov + 4,
4903       tlsdesc_got_entry,
4904       plt_entry_address + 4);
4905
4906   // R_AARCH64_ADR_PREL_PG_HI21
4907   AArch64_relocate_functions<size, big_endian>::adrp(
4908       pov + 8,
4909       gotplt_address,
4910       plt_entry_address + 8);
4911
4912   // R_AARCH64_LDST64_ABS_LO12
4913   elfcpp::Swap<32, big_endian>::writeval(
4914       pov + 12,
4915       ((this->tlsdesc_plt_entry[3] & 0xffc003ff)
4916        | ((tlsdesc_got_entry & 0xff8) << 7)));
4917
4918   // R_AARCH64_ADD_ABS_LO12
4919   elfcpp::Swap<32, big_endian>::writeval(
4920       pov + 16,
4921       ((this->tlsdesc_plt_entry[4] & 0xffc003ff)
4922        | ((gotplt_address & 0xfff) << 10)));
4923 }
4924
4925 // Write out the PLT.  This uses the hand-coded instructions above,
4926 // and adjusts them as needed.  This is specified by the AMD64 ABI.
4927
4928 template<int size, bool big_endian>
4929 void
4930 Output_data_plt_aarch64<size, big_endian>::do_write(Output_file* of)
4931 {
4932   const off_t offset = this->offset();
4933   const section_size_type oview_size =
4934     convert_to_section_size_type(this->data_size());
4935   unsigned char* const oview = of->get_output_view(offset, oview_size);
4936
4937   const off_t got_file_offset = this->got_plt_->offset();
4938   gold_assert(got_file_offset + this->got_plt_->data_size()
4939               == this->got_irelative_->offset());
4940
4941   const section_size_type got_size =
4942       convert_to_section_size_type(this->got_plt_->data_size()
4943                                    + this->got_irelative_->data_size());
4944   unsigned char* const got_view = of->get_output_view(got_file_offset,
4945                                                       got_size);
4946
4947   unsigned char* pov = oview;
4948
4949   // The base address of the .plt section.
4950   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
4951   // The base address of the PLT portion of the .got section.
4952   typename elfcpp::Elf_types<size>::Elf_Addr gotplt_address
4953       = this->got_plt_->address();
4954
4955   this->fill_first_plt_entry(pov, gotplt_address, plt_address);
4956   pov += this->first_plt_entry_offset();
4957
4958   // The first three entries in .got.plt are reserved.
4959   unsigned char* got_pov = got_view;
4960   memset(got_pov, 0, size / 8 * AARCH64_GOTPLT_RESERVE_COUNT);
4961   got_pov += (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
4962
4963   unsigned int plt_offset = this->first_plt_entry_offset();
4964   unsigned int got_offset = (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
4965   const unsigned int count = this->count_ + this->irelative_count_;
4966   for (unsigned int plt_index = 0;
4967        plt_index < count;
4968        ++plt_index,
4969          pov += this->get_plt_entry_size(),
4970          got_pov += size / 8,
4971          plt_offset += this->get_plt_entry_size(),
4972          got_offset += size / 8)
4973     {
4974       // Set and adjust the PLT entry itself.
4975       this->fill_plt_entry(pov, gotplt_address, plt_address,
4976                            got_offset, plt_offset);
4977
4978       // Set the entry in the GOT, which points to plt0.
4979       elfcpp::Swap<size, big_endian>::writeval(got_pov, plt_address);
4980     }
4981
4982   if (this->has_tlsdesc_entry())
4983     {
4984       // Set and adjust the reserved TLSDESC PLT entry.
4985       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
4986       // The base address of the .base section.
4987       typename elfcpp::Elf_types<size>::Elf_Addr got_base =
4988           this->got_->address();
4989       this->fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
4990                                tlsdesc_got_offset, plt_offset);
4991       pov += this->get_plt_tlsdesc_entry_size();
4992     }
4993
4994   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
4995   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
4996
4997   of->write_output_view(offset, oview_size, oview);
4998   of->write_output_view(got_file_offset, got_size, got_view);
4999 }
5000
5001 // Telling how to update the immediate field of an instruction.
5002 struct AArch64_howto
5003 {
5004   // The immediate field mask.
5005   elfcpp::Elf_Xword dst_mask;
5006
5007   // The offset to apply relocation immediate
5008   int doffset;
5009
5010   // The second part offset, if the immediate field has two parts.
5011   // -1 if the immediate field has only one part.
5012   int doffset2;
5013 };
5014
5015 static const AArch64_howto aarch64_howto[AArch64_reloc_property::INST_NUM] =
5016 {
5017   {0, -1, -1},          // DATA
5018   {0x1fffe0, 5, -1},    // MOVW  [20:5]-imm16
5019   {0xffffe0, 5, -1},    // LD    [23:5]-imm19
5020   {0x60ffffe0, 29, 5},  // ADR   [30:29]-immlo  [23:5]-immhi
5021   {0x60ffffe0, 29, 5},  // ADRP  [30:29]-immlo  [23:5]-immhi
5022   {0x3ffc00, 10, -1},   // ADD   [21:10]-imm12
5023   {0x3ffc00, 10, -1},   // LDST  [21:10]-imm12
5024   {0x7ffe0, 5, -1},     // TBZNZ [18:5]-imm14
5025   {0xffffe0, 5, -1},    // CONDB [23:5]-imm19
5026   {0x3ffffff, 0, -1},   // B     [25:0]-imm26
5027   {0x3ffffff, 0, -1},   // CALL  [25:0]-imm26
5028 };
5029
5030 // AArch64 relocate function class
5031
5032 template<int size, bool big_endian>
5033 class AArch64_relocate_functions
5034 {
5035  public:
5036   typedef enum
5037   {
5038     STATUS_OKAY,        // No error during relocation.
5039     STATUS_OVERFLOW,    // Relocation overflow.
5040     STATUS_BAD_RELOC,   // Relocation cannot be applied.
5041   } Status;
5042
5043   typedef AArch64_relocate_functions<size, big_endian> This;
5044   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
5045   typedef Relocate_info<size, big_endian> The_relocate_info;
5046   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
5047   typedef Reloc_stub<size, big_endian> The_reloc_stub;
5048   typedef Stub_table<size, big_endian> The_stub_table;
5049   typedef elfcpp::Rela<size, big_endian> The_rela;
5050   typedef typename elfcpp::Swap<size, big_endian>::Valtype AArch64_valtype;
5051
5052   // Return the page address of the address.
5053   // Page(address) = address & ~0xFFF
5054
5055   static inline AArch64_valtype
5056   Page(Address address)
5057   {
5058     return (address & (~static_cast<Address>(0xFFF)));
5059   }
5060
5061  private:
5062   // Update instruction (pointed by view) with selected bits (immed).
5063   // val = (val & ~dst_mask) | (immed << doffset)
5064
5065   template<int valsize>
5066   static inline void
5067   update_view(unsigned char* view,
5068               AArch64_valtype immed,
5069               elfcpp::Elf_Xword doffset,
5070               elfcpp::Elf_Xword dst_mask)
5071   {
5072     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5073     Valtype* wv = reinterpret_cast<Valtype*>(view);
5074     Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
5075
5076     // Clear immediate fields.
5077     val &= ~dst_mask;
5078     elfcpp::Swap<valsize, big_endian>::writeval(wv,
5079       static_cast<Valtype>(val | (immed << doffset)));
5080   }
5081
5082   // Update two parts of an instruction (pointed by view) with selected
5083   // bits (immed1 and immed2).
5084   // val = (val & ~dst_mask) | (immed1 << doffset1) | (immed2 << doffset2)
5085
5086   template<int valsize>
5087   static inline void
5088   update_view_two_parts(
5089     unsigned char* view,
5090     AArch64_valtype immed1,
5091     AArch64_valtype immed2,
5092     elfcpp::Elf_Xword doffset1,
5093     elfcpp::Elf_Xword doffset2,
5094     elfcpp::Elf_Xword dst_mask)
5095   {
5096     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5097     Valtype* wv = reinterpret_cast<Valtype*>(view);
5098     Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
5099     val &= ~dst_mask;
5100     elfcpp::Swap<valsize, big_endian>::writeval(wv,
5101       static_cast<Valtype>(val | (immed1 << doffset1) |
5102                            (immed2 << doffset2)));
5103   }
5104
5105   // Update adr or adrp instruction with immed.
5106   // In adr and adrp: [30:29] immlo   [23:5] immhi
5107
5108   static inline void
5109   update_adr(unsigned char* view, AArch64_valtype immed)
5110   {
5111     elfcpp::Elf_Xword dst_mask = (0x3 << 29) | (0x7ffff << 5);
5112     This::template update_view_two_parts<32>(
5113       view,
5114       immed & 0x3,
5115       (immed & 0x1ffffc) >> 2,
5116       29,
5117       5,
5118       dst_mask);
5119   }
5120
5121   // Update movz/movn instruction with bits immed.
5122   // Set instruction to movz if is_movz is true, otherwise set instruction
5123   // to movn.
5124
5125   static inline void
5126   update_movnz(unsigned char* view,
5127                AArch64_valtype immed,
5128                bool is_movz)
5129   {
5130     typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5131     Valtype* wv = reinterpret_cast<Valtype*>(view);
5132     Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
5133
5134     const elfcpp::Elf_Xword doffset =
5135         aarch64_howto[AArch64_reloc_property::INST_MOVW].doffset;
5136     const elfcpp::Elf_Xword dst_mask =
5137         aarch64_howto[AArch64_reloc_property::INST_MOVW].dst_mask;
5138
5139     // Clear immediate fields and opc code.
5140     val &= ~(dst_mask | (0x3 << 29));
5141
5142     // Set instruction to movz or movn.
5143     // movz: [30:29] is 10   movn: [30:29] is 00
5144     if (is_movz)
5145       val |= (0x2 << 29);
5146
5147     elfcpp::Swap<32, big_endian>::writeval(wv,
5148       static_cast<Valtype>(val | (immed << doffset)));
5149   }
5150
5151  public:
5152
5153   // Update selected bits in text.
5154
5155   template<int valsize>
5156   static inline typename This::Status
5157   reloc_common(unsigned char* view, Address x,
5158                 const AArch64_reloc_property* reloc_property)
5159   {
5160     // Select bits from X.
5161     Address immed = reloc_property->select_x_value(x);
5162
5163     // Update view.
5164     const AArch64_reloc_property::Reloc_inst inst =
5165       reloc_property->reloc_inst();
5166     // If it is a data relocation or instruction has 2 parts of immediate
5167     // fields, you should not call pcrela_general.
5168     gold_assert(aarch64_howto[inst].doffset2 == -1 &&
5169                 aarch64_howto[inst].doffset != -1);
5170     This::template update_view<valsize>(view, immed,
5171                                         aarch64_howto[inst].doffset,
5172                                         aarch64_howto[inst].dst_mask);
5173
5174     // Do check overflow or alignment if needed.
5175     return (reloc_property->checkup_x_value(x)
5176             ? This::STATUS_OKAY
5177             : This::STATUS_OVERFLOW);
5178   }
5179
5180   // Construct a B insn. Note, although we group it here with other relocation
5181   // operation, there is actually no 'relocation' involved here.
5182   static inline void
5183   construct_b(unsigned char* view, unsigned int branch_offset)
5184   {
5185     update_view_two_parts<32>(view, 0x05, (branch_offset >> 2),
5186                               26, 0, 0xffffffff);
5187   }
5188
5189   // Do a simple rela relocation at unaligned addresses.
5190
5191   template<int valsize>
5192   static inline typename This::Status
5193   rela_ua(unsigned char* view,
5194           const Sized_relobj_file<size, big_endian>* object,
5195           const Symbol_value<size>* psymval,
5196           AArch64_valtype addend,
5197           const AArch64_reloc_property* reloc_property)
5198   {
5199     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
5200       Valtype;
5201     typename elfcpp::Elf_types<size>::Elf_Addr x =
5202         psymval->value(object, addend);
5203     elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
5204       static_cast<Valtype>(x));
5205     return (reloc_property->checkup_x_value(x)
5206             ? This::STATUS_OKAY
5207             : This::STATUS_OVERFLOW);
5208   }
5209
5210   // Do a simple pc-relative relocation at unaligned addresses.
5211
5212   template<int valsize>
5213   static inline typename This::Status
5214   pcrela_ua(unsigned char* view,
5215             const Sized_relobj_file<size, big_endian>* object,
5216             const Symbol_value<size>* psymval,
5217             AArch64_valtype addend,
5218             Address address,
5219             const AArch64_reloc_property* reloc_property)
5220   {
5221     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
5222       Valtype;
5223     Address x = psymval->value(object, addend) - address;
5224     elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
5225       static_cast<Valtype>(x));
5226     return (reloc_property->checkup_x_value(x)
5227             ? This::STATUS_OKAY
5228             : This::STATUS_OVERFLOW);
5229   }
5230
5231   // Do a simple rela relocation at aligned addresses.
5232
5233   template<int valsize>
5234   static inline typename This::Status
5235   rela(
5236     unsigned char* view,
5237     const Sized_relobj_file<size, big_endian>* object,
5238     const Symbol_value<size>* psymval,
5239     AArch64_valtype addend,
5240     const AArch64_reloc_property* reloc_property)
5241   {
5242     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5243     Valtype* wv = reinterpret_cast<Valtype*>(view);
5244     Address x = psymval->value(object, addend);
5245     elfcpp::Swap<valsize, big_endian>::writeval(wv,static_cast<Valtype>(x));
5246     return (reloc_property->checkup_x_value(x)
5247             ? This::STATUS_OKAY
5248             : This::STATUS_OVERFLOW);
5249   }
5250
5251   // Do relocate. Update selected bits in text.
5252   // new_val = (val & ~dst_mask) | (immed << doffset)
5253
5254   template<int valsize>
5255   static inline typename This::Status
5256   rela_general(unsigned char* view,
5257                const Sized_relobj_file<size, big_endian>* object,
5258                const Symbol_value<size>* psymval,
5259                AArch64_valtype addend,
5260                const AArch64_reloc_property* reloc_property)
5261   {
5262     // Calculate relocation.
5263     Address x = psymval->value(object, addend);
5264     return This::template reloc_common<valsize>(view, x, reloc_property);
5265   }
5266
5267   // Do relocate. Update selected bits in text.
5268   // new val = (val & ~dst_mask) | (immed << doffset)
5269
5270   template<int valsize>
5271   static inline typename This::Status
5272   rela_general(
5273     unsigned char* view,
5274     AArch64_valtype s,
5275     AArch64_valtype addend,
5276     const AArch64_reloc_property* reloc_property)
5277   {
5278     // Calculate relocation.
5279     Address x = s + addend;
5280     return This::template reloc_common<valsize>(view, x, reloc_property);
5281   }
5282
5283   // Do address relative relocate. Update selected bits in text.
5284   // new val = (val & ~dst_mask) | (immed << doffset)
5285
5286   template<int valsize>
5287   static inline typename This::Status
5288   pcrela_general(
5289     unsigned char* view,
5290     const Sized_relobj_file<size, big_endian>* object,
5291     const Symbol_value<size>* psymval,
5292     AArch64_valtype addend,
5293     Address address,
5294     const AArch64_reloc_property* reloc_property)
5295   {
5296     // Calculate relocation.
5297     Address x = psymval->value(object, addend) - address;
5298     return This::template reloc_common<valsize>(view, x, reloc_property);
5299   }
5300
5301
5302   // Calculate (S + A) - address, update adr instruction.
5303
5304   static inline typename This::Status
5305   adr(unsigned char* view,
5306       const Sized_relobj_file<size, big_endian>* object,
5307       const Symbol_value<size>* psymval,
5308       Address addend,
5309       Address address,
5310       const AArch64_reloc_property* /* reloc_property */)
5311   {
5312     AArch64_valtype x = psymval->value(object, addend) - address;
5313     // Pick bits [20:0] of X.
5314     AArch64_valtype immed = x & 0x1fffff;
5315     update_adr(view, immed);
5316     // Check -2^20 <= X < 2^20
5317     return (size == 64 && Bits<21>::has_overflow((x))
5318             ? This::STATUS_OVERFLOW
5319             : This::STATUS_OKAY);
5320   }
5321
5322   // Calculate PG(S+A) - PG(address), update adrp instruction.
5323   // R_AARCH64_ADR_PREL_PG_HI21
5324
5325   static inline typename This::Status
5326   adrp(
5327     unsigned char* view,
5328     Address sa,
5329     Address address)
5330   {
5331     AArch64_valtype x = This::Page(sa) - This::Page(address);
5332     // Pick [32:12] of X.
5333     AArch64_valtype immed = (x >> 12) & 0x1fffff;
5334     update_adr(view, immed);
5335     // Check -2^32 <= X < 2^32
5336     return (size == 64 && Bits<33>::has_overflow((x))
5337             ? This::STATUS_OVERFLOW
5338             : This::STATUS_OKAY);
5339   }
5340
5341   // Calculate PG(S+A) - PG(address), update adrp instruction.
5342   // R_AARCH64_ADR_PREL_PG_HI21
5343
5344   static inline typename This::Status
5345   adrp(unsigned char* view,
5346        const Sized_relobj_file<size, big_endian>* object,
5347        const Symbol_value<size>* psymval,
5348        Address addend,
5349        Address address,
5350        const AArch64_reloc_property* reloc_property)
5351   {
5352     Address sa = psymval->value(object, addend);
5353     AArch64_valtype x = This::Page(sa) - This::Page(address);
5354     // Pick [32:12] of X.
5355     AArch64_valtype immed = (x >> 12) & 0x1fffff;
5356     update_adr(view, immed);
5357     return (reloc_property->checkup_x_value(x)
5358             ? This::STATUS_OKAY
5359             : This::STATUS_OVERFLOW);
5360   }
5361
5362   // Update mov[n/z] instruction. Check overflow if needed.
5363   // If X >=0, set the instruction to movz and its immediate value to the
5364   // selected bits S.
5365   // If X < 0, set the instruction to movn and its immediate value to
5366   // NOT (selected bits of).
5367
5368   static inline typename This::Status
5369   movnz(unsigned char* view,
5370         AArch64_valtype x,
5371         const AArch64_reloc_property* reloc_property)
5372   {
5373     // Select bits from X.
5374     Address immed;
5375     bool is_movz;
5376     typedef typename elfcpp::Elf_types<size>::Elf_Swxword SignedW;
5377     if (static_cast<SignedW>(x) >= 0)
5378       {
5379         immed = reloc_property->select_x_value(x);
5380         is_movz = true;
5381       }
5382     else
5383       {
5384         immed = reloc_property->select_x_value(~x);;
5385         is_movz = false;
5386       }
5387
5388     // Update movnz instruction.
5389     update_movnz(view, immed, is_movz);
5390
5391     // Do check overflow or alignment if needed.
5392     return (reloc_property->checkup_x_value(x)
5393             ? This::STATUS_OKAY
5394             : This::STATUS_OVERFLOW);
5395   }
5396
5397   static inline bool
5398   maybe_apply_stub(unsigned int,
5399                    const The_relocate_info*,
5400                    const The_rela&,
5401                    unsigned char*,
5402                    Address,
5403                    const Sized_symbol<size>*,
5404                    const Symbol_value<size>*,
5405                    const Sized_relobj_file<size, big_endian>*,
5406                    section_size_type);
5407
5408 };  // End of AArch64_relocate_functions
5409
5410
5411 // For a certain relocation type (usually jump/branch), test to see if the
5412 // destination needs a stub to fulfil. If so, re-route the destination of the
5413 // original instruction to the stub, note, at this time, the stub has already
5414 // been generated.
5415
5416 template<int size, bool big_endian>
5417 bool
5418 AArch64_relocate_functions<size, big_endian>::
5419 maybe_apply_stub(unsigned int r_type,
5420                  const The_relocate_info* relinfo,
5421                  const The_rela& rela,
5422                  unsigned char* view,
5423                  Address address,
5424                  const Sized_symbol<size>* gsym,
5425                  const Symbol_value<size>* psymval,
5426                  const Sized_relobj_file<size, big_endian>* object,
5427                  section_size_type current_group_size)
5428 {
5429   if (parameters->options().relocatable())
5430     return false;
5431
5432   typename elfcpp::Elf_types<size>::Elf_Swxword addend = rela.get_r_addend();
5433   Address branch_target = psymval->value(object, 0) + addend;
5434   int stub_type =
5435     The_reloc_stub::stub_type_for_reloc(r_type, address, branch_target);
5436   if (stub_type == ST_NONE)
5437     return false;
5438
5439   const The_aarch64_relobj* aarch64_relobj =
5440       static_cast<const The_aarch64_relobj*>(object);
5441   // We don't create stubs for undefined symbols so don't look for one.
5442   if (gsym && gsym->is_undefined())
5443     {
5444       gold_debug(DEBUG_TARGET,
5445                  "stub: looking for a stub for undefined symbol %s in file %s",
5446                  gsym->name(), aarch64_relobj->name().c_str());
5447       return false;
5448     }
5449
5450   The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
5451   gold_assert(stub_table != NULL);
5452
5453   unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
5454   typename The_reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
5455   The_reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
5456   gold_assert(stub != NULL);
5457
5458   Address new_branch_target = stub_table->address() + stub->offset();
5459   typename elfcpp::Swap<size, big_endian>::Valtype branch_offset =
5460       new_branch_target - address;
5461   const AArch64_reloc_property* arp =
5462       aarch64_reloc_property_table->get_reloc_property(r_type);
5463   gold_assert(arp != NULL);
5464   typename This::Status status = This::template
5465       rela_general<32>(view, branch_offset, 0, arp);
5466   if (status != This::STATUS_OKAY)
5467     gold_error(_("Stub is too far away, try a smaller value "
5468                  "for '--stub-group-size'. The current value is 0x%lx."),
5469                static_cast<unsigned long>(current_group_size));
5470   return true;
5471 }
5472
5473
5474 // Group input sections for stub generation.
5475 //
5476 // We group input sections in an output section so that the total size,
5477 // including any padding space due to alignment is smaller than GROUP_SIZE
5478 // unless the only input section in group is bigger than GROUP_SIZE already.
5479 // Then an ARM stub table is created to follow the last input section
5480 // in group.  For each group an ARM stub table is created an is placed
5481 // after the last group.  If STUB_ALWAYS_AFTER_BRANCH is false, we further
5482 // extend the group after the stub table.
5483
5484 template<int size, bool big_endian>
5485 void
5486 Target_aarch64<size, big_endian>::group_sections(
5487     Layout* layout,
5488     section_size_type group_size,
5489     bool stubs_always_after_branch,
5490     const Task* task)
5491 {
5492   // Group input sections and insert stub table
5493   Layout::Section_list section_list;
5494   layout->get_executable_sections(&section_list);
5495   for (Layout::Section_list::const_iterator p = section_list.begin();
5496        p != section_list.end();
5497        ++p)
5498     {
5499       AArch64_output_section<size, big_endian>* output_section =
5500           static_cast<AArch64_output_section<size, big_endian>*>(*p);
5501       output_section->group_sections(group_size, stubs_always_after_branch,
5502                                      this, task);
5503     }
5504 }
5505
5506
5507 // Find the AArch64_input_section object corresponding to the SHNDX-th input
5508 // section of RELOBJ.
5509
5510 template<int size, bool big_endian>
5511 AArch64_input_section<size, big_endian>*
5512 Target_aarch64<size, big_endian>::find_aarch64_input_section(
5513     Relobj* relobj, unsigned int shndx) const
5514 {
5515   Section_id sid(relobj, shndx);
5516   typename AArch64_input_section_map::const_iterator p =
5517     this->aarch64_input_section_map_.find(sid);
5518   return (p != this->aarch64_input_section_map_.end()) ? p->second : NULL;
5519 }
5520
5521
5522 // Make a new AArch64_input_section object.
5523
5524 template<int size, bool big_endian>
5525 AArch64_input_section<size, big_endian>*
5526 Target_aarch64<size, big_endian>::new_aarch64_input_section(
5527     Relobj* relobj, unsigned int shndx)
5528 {
5529   Section_id sid(relobj, shndx);
5530
5531   AArch64_input_section<size, big_endian>* input_section =
5532       new AArch64_input_section<size, big_endian>(relobj, shndx);
5533   input_section->init();
5534
5535   // Register new AArch64_input_section in map for look-up.
5536   std::pair<typename AArch64_input_section_map::iterator,bool> ins =
5537       this->aarch64_input_section_map_.insert(
5538           std::make_pair(sid, input_section));
5539
5540   // Make sure that it we have not created another AArch64_input_section
5541   // for this input section already.
5542   gold_assert(ins.second);
5543
5544   return input_section;
5545 }
5546
5547
5548 // Relaxation hook.  This is where we do stub generation.
5549
5550 template<int size, bool big_endian>
5551 bool
5552 Target_aarch64<size, big_endian>::do_relax(
5553     int pass,
5554     const Input_objects* input_objects,
5555     Symbol_table* symtab,
5556     Layout* layout ,
5557     const Task* task)
5558 {
5559   gold_assert(!parameters->options().relocatable());
5560   if (pass == 1)
5561     {
5562       // We don't handle negative stub_group_size right now.
5563       this->stub_group_size_ = abs(parameters->options().stub_group_size());
5564       if (this->stub_group_size_ == 1)
5565         {
5566           // Leave room for 4096 4-byte stub entries. If we exceed that, then we
5567           // will fail to link.  The user will have to relink with an explicit
5568           // group size option.
5569           this->stub_group_size_ = The_reloc_stub::MAX_BRANCH_OFFSET -
5570                                    4096 * 4;
5571         }
5572       group_sections(layout, this->stub_group_size_, true, task);
5573     }
5574   else
5575     {
5576       // If this is not the first pass, addresses and file offsets have
5577       // been reset at this point, set them here.
5578       for (Stub_table_iterator sp = this->stub_tables_.begin();
5579            sp != this->stub_tables_.end(); ++sp)
5580         {
5581           The_stub_table* stt = *sp;
5582           The_aarch64_input_section* owner = stt->owner();
5583           off_t off = align_address(owner->original_size(),
5584                                     stt->addralign());
5585           stt->set_address_and_file_offset(owner->address() + off,
5586                                            owner->offset() + off);
5587         }
5588     }
5589
5590   // Scan relocs for relocation stubs
5591   for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
5592        op != input_objects->relobj_end();
5593        ++op)
5594     {
5595       The_aarch64_relobj* aarch64_relobj =
5596           static_cast<The_aarch64_relobj*>(*op);
5597       // Lock the object so we can read from it.  This is only called
5598       // single-threaded from Layout::finalize, so it is OK to lock.
5599       Task_lock_obj<Object> tl(task, aarch64_relobj);
5600       aarch64_relobj->scan_sections_for_stubs(this, symtab, layout);
5601     }
5602
5603   bool any_stub_table_changed = false;
5604   for (Stub_table_iterator siter = this->stub_tables_.begin();
5605        siter != this->stub_tables_.end() && !any_stub_table_changed; ++siter)
5606     {
5607       The_stub_table* stub_table = *siter;
5608       if (stub_table->update_data_size_changed_p())
5609         {
5610           The_aarch64_input_section* owner = stub_table->owner();
5611           uint64_t address = owner->address();
5612           off_t offset = owner->offset();
5613           owner->reset_address_and_file_offset();
5614           owner->set_address_and_file_offset(address, offset);
5615
5616           any_stub_table_changed = true;
5617         }
5618     }
5619
5620   // Do not continue relaxation.
5621   bool continue_relaxation = any_stub_table_changed;
5622   if (!continue_relaxation)
5623     for (Stub_table_iterator sp = this->stub_tables_.begin();
5624          (sp != this->stub_tables_.end());
5625          ++sp)
5626       (*sp)->finalize_stubs();
5627
5628   return continue_relaxation;
5629 }
5630
5631
5632 // Make a new Stub_table.
5633
5634 template<int size, bool big_endian>
5635 Stub_table<size, big_endian>*
5636 Target_aarch64<size, big_endian>::new_stub_table(
5637     AArch64_input_section<size, big_endian>* owner)
5638 {
5639   Stub_table<size, big_endian>* stub_table =
5640       new Stub_table<size, big_endian>(owner);
5641   stub_table->set_address(align_address(
5642       owner->address() + owner->data_size(), 8));
5643   stub_table->set_file_offset(owner->offset() + owner->data_size());
5644   stub_table->finalize_data_size();
5645
5646   this->stub_tables_.push_back(stub_table);
5647
5648   return stub_table;
5649 }
5650
5651
5652 template<int size, bool big_endian>
5653 uint64_t
5654 Target_aarch64<size, big_endian>::do_reloc_addend(
5655     void* arg, unsigned int r_type, uint64_t) const
5656 {
5657   gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
5658   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
5659   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
5660   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
5661   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
5662   gold_assert(psymval->is_tls_symbol());
5663   // The value of a TLS symbol is the offset in the TLS segment.
5664   return psymval->value(ti.object, 0);
5665 }
5666
5667 // Return the number of entries in the PLT.
5668
5669 template<int size, bool big_endian>
5670 unsigned int
5671 Target_aarch64<size, big_endian>::plt_entry_count() const
5672 {
5673   if (this->plt_ == NULL)
5674     return 0;
5675   return this->plt_->entry_count();
5676 }
5677
5678 // Return the offset of the first non-reserved PLT entry.
5679
5680 template<int size, bool big_endian>
5681 unsigned int
5682 Target_aarch64<size, big_endian>::first_plt_entry_offset() const
5683 {
5684   return this->plt_->first_plt_entry_offset();
5685 }
5686
5687 // Return the size of each PLT entry.
5688
5689 template<int size, bool big_endian>
5690 unsigned int
5691 Target_aarch64<size, big_endian>::plt_entry_size() const
5692 {
5693   return this->plt_->get_plt_entry_size();
5694 }
5695
5696 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
5697
5698 template<int size, bool big_endian>
5699 void
5700 Target_aarch64<size, big_endian>::define_tls_base_symbol(
5701     Symbol_table* symtab, Layout* layout)
5702 {
5703   if (this->tls_base_symbol_defined_)
5704     return;
5705
5706   Output_segment* tls_segment = layout->tls_segment();
5707   if (tls_segment != NULL)
5708     {
5709       // _TLS_MODULE_BASE_ always points to the beginning of tls segment.
5710       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
5711                                        Symbol_table::PREDEFINED,
5712                                        tls_segment, 0, 0,
5713                                        elfcpp::STT_TLS,
5714                                        elfcpp::STB_LOCAL,
5715                                        elfcpp::STV_HIDDEN, 0,
5716                                        Symbol::SEGMENT_START,
5717                                        true);
5718     }
5719   this->tls_base_symbol_defined_ = true;
5720 }
5721
5722 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
5723
5724 template<int size, bool big_endian>
5725 void
5726 Target_aarch64<size, big_endian>::reserve_tlsdesc_entries(
5727     Symbol_table* symtab, Layout* layout)
5728 {
5729   if (this->plt_ == NULL)
5730     this->make_plt_section(symtab, layout);
5731
5732   if (!this->plt_->has_tlsdesc_entry())
5733     {
5734       // Allocate the TLSDESC_GOT entry.
5735       Output_data_got_aarch64<size, big_endian>* got =
5736           this->got_section(symtab, layout);
5737       unsigned int got_offset = got->add_constant(0);
5738
5739       // Allocate the TLSDESC_PLT entry.
5740       this->plt_->reserve_tlsdesc_entry(got_offset);
5741     }
5742 }
5743
5744 // Create a GOT entry for the TLS module index.
5745
5746 template<int size, bool big_endian>
5747 unsigned int
5748 Target_aarch64<size, big_endian>::got_mod_index_entry(
5749     Symbol_table* symtab, Layout* layout,
5750     Sized_relobj_file<size, big_endian>* object)
5751 {
5752   if (this->got_mod_index_offset_ == -1U)
5753     {
5754       gold_assert(symtab != NULL && layout != NULL && object != NULL);
5755       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
5756       Output_data_got_aarch64<size, big_endian>* got =
5757           this->got_section(symtab, layout);
5758       unsigned int got_offset = got->add_constant(0);
5759       rela_dyn->add_local(object, 0, elfcpp::R_AARCH64_TLS_DTPMOD64, got,
5760                           got_offset, 0);
5761       got->add_constant(0);
5762       this->got_mod_index_offset_ = got_offset;
5763     }
5764   return this->got_mod_index_offset_;
5765 }
5766
5767 // Optimize the TLS relocation type based on what we know about the
5768 // symbol.  IS_FINAL is true if the final address of this symbol is
5769 // known at link time.
5770
5771 template<int size, bool big_endian>
5772 tls::Tls_optimization
5773 Target_aarch64<size, big_endian>::optimize_tls_reloc(bool is_final,
5774                                                      int r_type)
5775 {
5776   // If we are generating a shared library, then we can't do anything
5777   // in the linker
5778   if (parameters->options().shared())
5779     return tls::TLSOPT_NONE;
5780
5781   switch (r_type)
5782     {
5783     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
5784     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
5785     case elfcpp::R_AARCH64_TLSDESC_LD_PREL19:
5786     case elfcpp::R_AARCH64_TLSDESC_ADR_PREL21:
5787     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
5788     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
5789     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
5790     case elfcpp::R_AARCH64_TLSDESC_OFF_G1:
5791     case elfcpp::R_AARCH64_TLSDESC_OFF_G0_NC:
5792     case elfcpp::R_AARCH64_TLSDESC_LDR:
5793     case elfcpp::R_AARCH64_TLSDESC_ADD:
5794     case elfcpp::R_AARCH64_TLSDESC_CALL:
5795       // These are General-Dynamic which permits fully general TLS
5796       // access.  Since we know that we are generating an executable,
5797       // we can convert this to Initial-Exec.  If we also know that
5798       // this is a local symbol, we can further switch to Local-Exec.
5799       if (is_final)
5800         return tls::TLSOPT_TO_LE;
5801       return tls::TLSOPT_TO_IE;
5802
5803     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
5804     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
5805     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
5806     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
5807     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
5808     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
5809       // These are Local-Dynamic, which refer to local symbols in the
5810       // dynamic TLS block. Since we know that we generating an
5811       // executable, we can switch to Local-Exec.
5812       return tls::TLSOPT_TO_LE;
5813
5814     case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G1:
5815     case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC:
5816     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
5817     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
5818     case elfcpp::R_AARCH64_TLSIE_LD_GOTTPREL_PREL19:
5819       // These are Initial-Exec relocs which get the thread offset
5820       // from the GOT. If we know that we are linking against the
5821       // local symbol, we can switch to Local-Exec, which links the
5822       // thread offset into the instruction.
5823       if (is_final)
5824         return tls::TLSOPT_TO_LE;
5825       return tls::TLSOPT_NONE;
5826
5827     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
5828     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
5829     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
5830     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
5831     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
5832     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
5833     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
5834     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
5835       // When we already have Local-Exec, there is nothing further we
5836       // can do.
5837       return tls::TLSOPT_NONE;
5838
5839     default:
5840       gold_unreachable();
5841     }
5842 }
5843
5844 // Returns true if this relocation type could be that of a function pointer.
5845
5846 template<int size, bool big_endian>
5847 inline bool
5848 Target_aarch64<size, big_endian>::Scan::possible_function_pointer_reloc(
5849   unsigned int r_type)
5850 {
5851   switch (r_type)
5852     {
5853     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
5854     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
5855     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
5856     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
5857     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
5858       {
5859         return true;
5860       }
5861     }
5862   return false;
5863 }
5864
5865 // For safe ICF, scan a relocation for a local symbol to check if it
5866 // corresponds to a function pointer being taken.  In that case mark
5867 // the function whose pointer was taken as not foldable.
5868
5869 template<int size, bool big_endian>
5870 inline bool
5871 Target_aarch64<size, big_endian>::Scan::local_reloc_may_be_function_pointer(
5872   Symbol_table* ,
5873   Layout* ,
5874   Target_aarch64<size, big_endian>* ,
5875   Sized_relobj_file<size, big_endian>* ,
5876   unsigned int ,
5877   Output_section* ,
5878   const elfcpp::Rela<size, big_endian>& ,
5879   unsigned int r_type,
5880   const elfcpp::Sym<size, big_endian>&)
5881 {
5882   // When building a shared library, do not fold any local symbols.
5883   return (parameters->options().shared()
5884           || possible_function_pointer_reloc(r_type));
5885 }
5886
5887 // For safe ICF, scan a relocation for a global symbol to check if it
5888 // corresponds to a function pointer being taken.  In that case mark
5889 // the function whose pointer was taken as not foldable.
5890
5891 template<int size, bool big_endian>
5892 inline bool
5893 Target_aarch64<size, big_endian>::Scan::global_reloc_may_be_function_pointer(
5894   Symbol_table* ,
5895   Layout* ,
5896   Target_aarch64<size, big_endian>* ,
5897   Sized_relobj_file<size, big_endian>* ,
5898   unsigned int ,
5899   Output_section* ,
5900   const elfcpp::Rela<size, big_endian>& ,
5901   unsigned int r_type,
5902   Symbol* gsym)
5903 {
5904   // When building a shared library, do not fold symbols whose visibility
5905   // is hidden, internal or protected.
5906   return ((parameters->options().shared()
5907            && (gsym->visibility() == elfcpp::STV_INTERNAL
5908                || gsym->visibility() == elfcpp::STV_PROTECTED
5909                || gsym->visibility() == elfcpp::STV_HIDDEN))
5910           || possible_function_pointer_reloc(r_type));
5911 }
5912
5913 // Report an unsupported relocation against a local symbol.
5914
5915 template<int size, bool big_endian>
5916 void
5917 Target_aarch64<size, big_endian>::Scan::unsupported_reloc_local(
5918      Sized_relobj_file<size, big_endian>* object,
5919      unsigned int r_type)
5920 {
5921   gold_error(_("%s: unsupported reloc %u against local symbol"),
5922              object->name().c_str(), r_type);
5923 }
5924
5925 // We are about to emit a dynamic relocation of type R_TYPE.  If the
5926 // dynamic linker does not support it, issue an error.
5927
5928 template<int size, bool big_endian>
5929 void
5930 Target_aarch64<size, big_endian>::Scan::check_non_pic(Relobj* object,
5931                                                       unsigned int r_type)
5932 {
5933   gold_assert(r_type != elfcpp::R_AARCH64_NONE);
5934
5935   switch (r_type)
5936     {
5937     // These are the relocation types supported by glibc for AARCH64.
5938     case elfcpp::R_AARCH64_NONE:
5939     case elfcpp::R_AARCH64_COPY:
5940     case elfcpp::R_AARCH64_GLOB_DAT:
5941     case elfcpp::R_AARCH64_JUMP_SLOT:
5942     case elfcpp::R_AARCH64_RELATIVE:
5943     case elfcpp::R_AARCH64_TLS_DTPREL64:
5944     case elfcpp::R_AARCH64_TLS_DTPMOD64:
5945     case elfcpp::R_AARCH64_TLS_TPREL64:
5946     case elfcpp::R_AARCH64_TLSDESC:
5947     case elfcpp::R_AARCH64_IRELATIVE:
5948     case elfcpp::R_AARCH64_ABS32:
5949     case elfcpp::R_AARCH64_ABS64:
5950       return;
5951
5952     default:
5953       break;
5954     }
5955
5956   // This prevents us from issuing more than one error per reloc
5957   // section. But we can still wind up issuing more than one
5958   // error per object file.
5959   if (this->issued_non_pic_error_)
5960     return;
5961   gold_assert(parameters->options().output_is_position_independent());
5962   object->error(_("requires unsupported dynamic reloc; "
5963                   "recompile with -fPIC"));
5964   this->issued_non_pic_error_ = true;
5965   return;
5966 }
5967
5968 // Return whether we need to make a PLT entry for a relocation of the
5969 // given type against a STT_GNU_IFUNC symbol.
5970
5971 template<int size, bool big_endian>
5972 bool
5973 Target_aarch64<size, big_endian>::Scan::reloc_needs_plt_for_ifunc(
5974     Sized_relobj_file<size, big_endian>* object,
5975     unsigned int r_type)
5976 {
5977   const AArch64_reloc_property* arp =
5978       aarch64_reloc_property_table->get_reloc_property(r_type);
5979   gold_assert(arp != NULL);
5980
5981   int flags = arp->reference_flags();
5982   if (flags & Symbol::TLS_REF)
5983     {
5984       gold_error(_("%s: unsupported TLS reloc %s for IFUNC symbol"),
5985                  object->name().c_str(), arp->name().c_str());
5986       return false;
5987     }
5988   return flags != 0;
5989 }
5990
5991 // Scan a relocation for a local symbol.
5992
5993 template<int size, bool big_endian>
5994 inline void
5995 Target_aarch64<size, big_endian>::Scan::local(
5996     Symbol_table* symtab,
5997     Layout* layout,
5998     Target_aarch64<size, big_endian>* target,
5999     Sized_relobj_file<size, big_endian>* object,
6000     unsigned int data_shndx,
6001     Output_section* output_section,
6002     const elfcpp::Rela<size, big_endian>& rela,
6003     unsigned int r_type,
6004     const elfcpp::Sym<size, big_endian>& lsym,
6005     bool is_discarded)
6006 {
6007   if (is_discarded)
6008     return;
6009
6010   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
6011       Reloc_section;
6012   unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
6013
6014   // A local STT_GNU_IFUNC symbol may require a PLT entry.
6015   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
6016   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
6017     target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
6018
6019   switch (r_type)
6020     {
6021     case elfcpp::R_AARCH64_NONE:
6022       break;
6023
6024     case elfcpp::R_AARCH64_ABS32:
6025     case elfcpp::R_AARCH64_ABS16:
6026       if (parameters->options().output_is_position_independent())
6027         {
6028           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6029                      object->name().c_str(), r_type);
6030         }
6031       break;
6032
6033     case elfcpp::R_AARCH64_ABS64:
6034       // If building a shared library or pie, we need to mark this as a dynmic
6035       // reloction, so that the dynamic loader can relocate it.
6036       if (parameters->options().output_is_position_independent())
6037         {
6038           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6039           rela_dyn->add_local_relative(object, r_sym,
6040                                        elfcpp::R_AARCH64_RELATIVE,
6041                                        output_section,
6042                                        data_shndx,
6043                                        rela.get_r_offset(),
6044                                        rela.get_r_addend(),
6045                                        is_ifunc);
6046         }
6047       break;
6048
6049     case elfcpp::R_AARCH64_PREL64:
6050     case elfcpp::R_AARCH64_PREL32:
6051     case elfcpp::R_AARCH64_PREL16:
6052       break;
6053
6054     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
6055     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
6056     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
6057       // The above relocations are used to access GOT entries.
6058       {
6059         Output_data_got_aarch64<size, big_endian>* got =
6060             target->got_section(symtab, layout);
6061         bool is_new = false;
6062         // This symbol requires a GOT entry.
6063         if (is_ifunc)
6064           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
6065         else
6066           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
6067         if (is_new && parameters->options().output_is_position_independent())
6068           target->rela_dyn_section(layout)->
6069             add_local_relative(object,
6070                                r_sym,
6071                                elfcpp::R_AARCH64_RELATIVE,
6072                                got,
6073                                object->local_got_offset(r_sym,
6074                                                         GOT_TYPE_STANDARD),
6075                                0,
6076                                false);
6077       }
6078       break;
6079
6080     case elfcpp::R_AARCH64_MOVW_UABS_G0:        // 263
6081     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:     // 264
6082     case elfcpp::R_AARCH64_MOVW_UABS_G1:        // 265
6083     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:     // 266
6084     case elfcpp::R_AARCH64_MOVW_UABS_G2:        // 267
6085     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:     // 268
6086     case elfcpp::R_AARCH64_MOVW_UABS_G3:        // 269
6087     case elfcpp::R_AARCH64_MOVW_SABS_G0:        // 270
6088     case elfcpp::R_AARCH64_MOVW_SABS_G1:        // 271
6089     case elfcpp::R_AARCH64_MOVW_SABS_G2:        // 272
6090       if (parameters->options().output_is_position_independent())
6091         {
6092           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6093                      object->name().c_str(), r_type);
6094         }
6095       break;
6096
6097     case elfcpp::R_AARCH64_LD_PREL_LO19:        // 273
6098     case elfcpp::R_AARCH64_ADR_PREL_LO21:       // 274
6099     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:    // 275
6100     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
6101     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:     // 277
6102     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:   // 278
6103     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:  // 284
6104     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:  // 285
6105     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:  // 286
6106     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
6107        break;
6108
6109     // Control flow, pc-relative. We don't need to do anything for a relative
6110     // addressing relocation against a local symbol if it does not reference
6111     // the GOT.
6112     case elfcpp::R_AARCH64_TSTBR14:
6113     case elfcpp::R_AARCH64_CONDBR19:
6114     case elfcpp::R_AARCH64_JUMP26:
6115     case elfcpp::R_AARCH64_CALL26:
6116       break;
6117
6118     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
6119     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
6120       {
6121         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6122           optimize_tls_reloc(!parameters->options().shared(), r_type);
6123         if (tlsopt == tls::TLSOPT_TO_LE)
6124           break;
6125
6126         layout->set_has_static_tls();
6127         // Create a GOT entry for the tp-relative offset.
6128         if (!parameters->doing_static_link())
6129           {
6130             Output_data_got_aarch64<size, big_endian>* got =
6131                 target->got_section(symtab, layout);
6132             got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
6133                                     target->rela_dyn_section(layout),
6134                                     elfcpp::R_AARCH64_TLS_TPREL64);
6135           }
6136         else if (!object->local_has_got_offset(r_sym,
6137                                                GOT_TYPE_TLS_OFFSET))
6138           {
6139             Output_data_got_aarch64<size, big_endian>* got =
6140                 target->got_section(symtab, layout);
6141             got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
6142             unsigned int got_offset =
6143                 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
6144             const elfcpp::Elf_Xword addend = rela.get_r_addend();
6145             gold_assert(addend == 0);
6146             got->add_static_reloc(got_offset, elfcpp::R_AARCH64_TLS_TPREL64,
6147                                   object, r_sym);
6148           }
6149       }
6150       break;
6151
6152     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
6153     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
6154       {
6155         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6156             optimize_tls_reloc(!parameters->options().shared(), r_type);
6157         if (tlsopt == tls::TLSOPT_TO_LE)
6158           {
6159             layout->set_has_static_tls();
6160             break;
6161           }
6162         gold_assert(tlsopt == tls::TLSOPT_NONE);
6163
6164         Output_data_got_aarch64<size, big_endian>* got =
6165             target->got_section(symtab, layout);
6166         got->add_local_pair_with_rel(object,r_sym, data_shndx,
6167                                      GOT_TYPE_TLS_PAIR,
6168                                      target->rela_dyn_section(layout),
6169                                      elfcpp::R_AARCH64_TLS_DTPMOD64);
6170       }
6171       break;
6172
6173     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
6174     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
6175     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
6176     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
6177     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
6178     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
6179     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
6180     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
6181       {
6182         layout->set_has_static_tls();
6183         bool output_is_shared = parameters->options().shared();
6184         if (output_is_shared)
6185           gold_error(_("%s: unsupported TLSLE reloc %u in shared code."),
6186                      object->name().c_str(), r_type);
6187       }
6188       break;
6189
6190     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
6191     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
6192       {
6193         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6194             optimize_tls_reloc(!parameters->options().shared(), r_type);
6195         if (tlsopt == tls::TLSOPT_NONE)
6196           {
6197             // Create a GOT entry for the module index.
6198             target->got_mod_index_entry(symtab, layout, object);
6199           }
6200         else if (tlsopt != tls::TLSOPT_TO_LE)
6201           unsupported_reloc_local(object, r_type);
6202       }
6203       break;
6204
6205     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
6206     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
6207     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
6208     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
6209       break;
6210
6211     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
6212     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
6213     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
6214       {
6215         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6216             optimize_tls_reloc(!parameters->options().shared(), r_type);
6217         target->define_tls_base_symbol(symtab, layout);
6218         if (tlsopt == tls::TLSOPT_NONE)
6219           {
6220             // Create reserved PLT and GOT entries for the resolver.
6221             target->reserve_tlsdesc_entries(symtab, layout);
6222
6223             // Generate a double GOT entry with an R_AARCH64_TLSDESC reloc.
6224             // The R_AARCH64_TLSDESC reloc is resolved lazily, so the GOT
6225             // entry needs to be in an area in .got.plt, not .got. Call
6226             // got_section to make sure the section has been created.
6227             target->got_section(symtab, layout);
6228             Output_data_got<size, big_endian>* got =
6229                 target->got_tlsdesc_section();
6230             unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
6231             if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
6232               {
6233                 unsigned int got_offset = got->add_constant(0);
6234                 got->add_constant(0);
6235                 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
6236                                              got_offset);
6237                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
6238                 // We store the arguments we need in a vector, and use
6239                 // the index into the vector as the parameter to pass
6240                 // to the target specific routines.
6241                 uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
6242                 void* arg = reinterpret_cast<void*>(intarg);
6243                 rt->add_target_specific(elfcpp::R_AARCH64_TLSDESC, arg,
6244                                         got, got_offset, 0);
6245               }
6246           }
6247         else if (tlsopt != tls::TLSOPT_TO_LE)
6248           unsupported_reloc_local(object, r_type);
6249       }
6250       break;
6251
6252     case elfcpp::R_AARCH64_TLSDESC_CALL:
6253       break;
6254
6255     default:
6256       unsupported_reloc_local(object, r_type);
6257     }
6258 }
6259
6260
6261 // Report an unsupported relocation against a global symbol.
6262
6263 template<int size, bool big_endian>
6264 void
6265 Target_aarch64<size, big_endian>::Scan::unsupported_reloc_global(
6266     Sized_relobj_file<size, big_endian>* object,
6267     unsigned int r_type,
6268     Symbol* gsym)
6269 {
6270   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
6271              object->name().c_str(), r_type, gsym->demangled_name().c_str());
6272 }
6273
6274 template<int size, bool big_endian>
6275 inline void
6276 Target_aarch64<size, big_endian>::Scan::global(
6277     Symbol_table* symtab,
6278     Layout* layout,
6279     Target_aarch64<size, big_endian>* target,
6280     Sized_relobj_file<size, big_endian> * object,
6281     unsigned int data_shndx,
6282     Output_section* output_section,
6283     const elfcpp::Rela<size, big_endian>& rela,
6284     unsigned int r_type,
6285     Symbol* gsym)
6286 {
6287   // A STT_GNU_IFUNC symbol may require a PLT entry.
6288   if (gsym->type() == elfcpp::STT_GNU_IFUNC
6289       && this->reloc_needs_plt_for_ifunc(object, r_type))
6290     target->make_plt_entry(symtab, layout, gsym);
6291
6292   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
6293     Reloc_section;
6294   const AArch64_reloc_property* arp =
6295       aarch64_reloc_property_table->get_reloc_property(r_type);
6296   gold_assert(arp != NULL);
6297
6298   switch (r_type)
6299     {
6300     case elfcpp::R_AARCH64_NONE:
6301       break;
6302
6303     case elfcpp::R_AARCH64_ABS16:
6304     case elfcpp::R_AARCH64_ABS32:
6305     case elfcpp::R_AARCH64_ABS64:
6306       {
6307         // Make a PLT entry if necessary.
6308         if (gsym->needs_plt_entry())
6309           {
6310             target->make_plt_entry(symtab, layout, gsym);
6311             // Since this is not a PC-relative relocation, we may be
6312             // taking the address of a function. In that case we need to
6313             // set the entry in the dynamic symbol table to the address of
6314             // the PLT entry.
6315             if (gsym->is_from_dynobj() && !parameters->options().shared())
6316               gsym->set_needs_dynsym_value();
6317           }
6318         // Make a dynamic relocation if necessary.
6319         if (gsym->needs_dynamic_reloc(arp->reference_flags()))
6320           {
6321             if (!parameters->options().output_is_position_independent()
6322                 && gsym->may_need_copy_reloc())
6323               {
6324                 target->copy_reloc(symtab, layout, object,
6325                                    data_shndx, output_section, gsym, rela);
6326               }
6327             else if (r_type == elfcpp::R_AARCH64_ABS64
6328                      && gsym->type() == elfcpp::STT_GNU_IFUNC
6329                      && gsym->can_use_relative_reloc(false)
6330                      && !gsym->is_from_dynobj()
6331                      && !gsym->is_undefined()
6332                      && !gsym->is_preemptible())
6333               {
6334                 // Use an IRELATIVE reloc for a locally defined STT_GNU_IFUNC
6335                 // symbol. This makes a function address in a PIE executable
6336                 // match the address in a shared library that it links against.
6337                 Reloc_section* rela_dyn =
6338                     target->rela_irelative_section(layout);
6339                 unsigned int r_type = elfcpp::R_AARCH64_IRELATIVE;
6340                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
6341                                                        output_section, object,
6342                                                        data_shndx,
6343                                                        rela.get_r_offset(),
6344                                                        rela.get_r_addend());
6345               }
6346             else if (r_type == elfcpp::R_AARCH64_ABS64
6347                      && gsym->can_use_relative_reloc(false))
6348               {
6349                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6350                 rela_dyn->add_global_relative(gsym,
6351                                               elfcpp::R_AARCH64_RELATIVE,
6352                                               output_section,
6353                                               object,
6354                                               data_shndx,
6355                                               rela.get_r_offset(),
6356                                               rela.get_r_addend(),
6357                                               false);
6358               }
6359             else
6360               {
6361                 check_non_pic(object, r_type);
6362                 Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>*
6363                     rela_dyn = target->rela_dyn_section(layout);
6364                 rela_dyn->add_global(
6365                   gsym, r_type, output_section, object,
6366                   data_shndx, rela.get_r_offset(),rela.get_r_addend());
6367               }
6368           }
6369       }
6370       break;
6371
6372     case elfcpp::R_AARCH64_PREL16:
6373     case elfcpp::R_AARCH64_PREL32:
6374     case elfcpp::R_AARCH64_PREL64:
6375       // This is used to fill the GOT absolute address.
6376       if (gsym->needs_plt_entry())
6377         {
6378           target->make_plt_entry(symtab, layout, gsym);
6379         }
6380       break;
6381
6382     case elfcpp::R_AARCH64_MOVW_UABS_G0:        // 263
6383     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:     // 264
6384     case elfcpp::R_AARCH64_MOVW_UABS_G1:        // 265
6385     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:     // 266
6386     case elfcpp::R_AARCH64_MOVW_UABS_G2:        // 267
6387     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:     // 268
6388     case elfcpp::R_AARCH64_MOVW_UABS_G3:        // 269
6389     case elfcpp::R_AARCH64_MOVW_SABS_G0:        // 270
6390     case elfcpp::R_AARCH64_MOVW_SABS_G1:        // 271
6391     case elfcpp::R_AARCH64_MOVW_SABS_G2:        // 272
6392       if (parameters->options().output_is_position_independent())
6393         {
6394           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6395                      object->name().c_str(), r_type);
6396         }
6397       break;
6398
6399     case elfcpp::R_AARCH64_LD_PREL_LO19:        // 273
6400     case elfcpp::R_AARCH64_ADR_PREL_LO21:       // 274
6401     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:    // 275
6402     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
6403     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:     // 277
6404     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:   // 278
6405     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:  // 284
6406     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:  // 285
6407     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:  // 286
6408     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
6409       {
6410         if (gsym->needs_plt_entry())
6411           target->make_plt_entry(symtab, layout, gsym);
6412         // Make a dynamic relocation if necessary.
6413         if (gsym->needs_dynamic_reloc(arp->reference_flags()))
6414           {
6415             if (parameters->options().output_is_executable()
6416                 && gsym->may_need_copy_reloc())
6417               {
6418                 target->copy_reloc(symtab, layout, object,
6419                                    data_shndx, output_section, gsym, rela);
6420               }
6421           }
6422         break;
6423       }
6424
6425     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
6426     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
6427     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
6428       {
6429         // The above relocations are used to access GOT entries.
6430         // Note a GOT entry is an *address* to a symbol.
6431         // The symbol requires a GOT entry
6432         Output_data_got_aarch64<size, big_endian>* got =
6433           target->got_section(symtab, layout);
6434         if (gsym->final_value_is_known())
6435           {
6436             // For a STT_GNU_IFUNC symbol we want the PLT address.
6437             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
6438               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
6439             else
6440               got->add_global(gsym, GOT_TYPE_STANDARD);
6441           }
6442         else
6443           {
6444             // If this symbol is not fully resolved, we need to add a dynamic
6445             // relocation for it.
6446             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6447
6448             // Use a GLOB_DAT rather than a RELATIVE reloc if:
6449             //
6450             // 1) The symbol may be defined in some other module.
6451             // 2) We are building a shared library and this is a protected
6452             // symbol; using GLOB_DAT means that the dynamic linker can use
6453             // the address of the PLT in the main executable when appropriate
6454             // so that function address comparisons work.
6455             // 3) This is a STT_GNU_IFUNC symbol in position dependent code,
6456             // again so that function address comparisons work.
6457             if (gsym->is_from_dynobj()
6458                 || gsym->is_undefined()
6459                 || gsym->is_preemptible()
6460                 || (gsym->visibility() == elfcpp::STV_PROTECTED
6461                     && parameters->options().shared())
6462                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
6463                     && parameters->options().output_is_position_independent()))
6464               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
6465                                        rela_dyn, elfcpp::R_AARCH64_GLOB_DAT);
6466             else
6467               {
6468                 // For a STT_GNU_IFUNC symbol we want to write the PLT
6469                 // offset into the GOT, so that function pointer
6470                 // comparisons work correctly.
6471                 bool is_new;
6472                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
6473                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
6474                 else
6475                   {
6476                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
6477                     // Tell the dynamic linker to use the PLT address
6478                     // when resolving relocations.
6479                     if (gsym->is_from_dynobj()
6480                         && !parameters->options().shared())
6481                       gsym->set_needs_dynsym_value();
6482                   }
6483                 if (is_new)
6484                   {
6485                     rela_dyn->add_global_relative(
6486                         gsym, elfcpp::R_AARCH64_RELATIVE,
6487                         got,
6488                         gsym->got_offset(GOT_TYPE_STANDARD),
6489                         0,
6490                         false);
6491                   }
6492               }
6493           }
6494         break;
6495       }
6496
6497     case elfcpp::R_AARCH64_TSTBR14:
6498     case elfcpp::R_AARCH64_CONDBR19:
6499     case elfcpp::R_AARCH64_JUMP26:
6500     case elfcpp::R_AARCH64_CALL26:
6501       {
6502         if (gsym->final_value_is_known())
6503           break;
6504
6505         if (gsym->is_defined() &&
6506             !gsym->is_from_dynobj() &&
6507             !gsym->is_preemptible())
6508           break;
6509
6510         // Make plt entry for function call.
6511         target->make_plt_entry(symtab, layout, gsym);
6512         break;
6513       }
6514
6515     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
6516     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:  // General dynamic
6517       {
6518         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6519             optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6520         if (tlsopt == tls::TLSOPT_TO_LE)
6521           {
6522             layout->set_has_static_tls();
6523             break;
6524           }
6525         gold_assert(tlsopt == tls::TLSOPT_NONE);
6526
6527         // General dynamic.
6528         Output_data_got_aarch64<size, big_endian>* got =
6529             target->got_section(symtab, layout);
6530         // Create 2 consecutive entries for module index and offset.
6531         got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
6532                                       target->rela_dyn_section(layout),
6533                                       elfcpp::R_AARCH64_TLS_DTPMOD64,
6534                                       elfcpp::R_AARCH64_TLS_DTPREL64);
6535       }
6536       break;
6537
6538     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
6539     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:  // Local dynamic
6540       {
6541         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6542             optimize_tls_reloc(!parameters->options().shared(), r_type);
6543         if (tlsopt == tls::TLSOPT_NONE)
6544           {
6545             // Create a GOT entry for the module index.
6546             target->got_mod_index_entry(symtab, layout, object);
6547           }
6548         else if (tlsopt != tls::TLSOPT_TO_LE)
6549           unsupported_reloc_local(object, r_type);
6550       }
6551       break;
6552
6553     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
6554     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
6555     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
6556     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:  // Other local dynamic
6557       break;
6558
6559     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
6560     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:  // Initial executable
6561       {
6562         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6563           optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6564         if (tlsopt == tls::TLSOPT_TO_LE)
6565           break;
6566
6567         layout->set_has_static_tls();
6568         // Create a GOT entry for the tp-relative offset.
6569         Output_data_got_aarch64<size, big_endian>* got
6570           = target->got_section(symtab, layout);
6571         if (!parameters->doing_static_link())
6572           {
6573             got->add_global_with_rel(
6574               gsym, GOT_TYPE_TLS_OFFSET,
6575               target->rela_dyn_section(layout),
6576               elfcpp::R_AARCH64_TLS_TPREL64);
6577           }
6578         if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
6579           {
6580             got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
6581             unsigned int got_offset =
6582               gsym->got_offset(GOT_TYPE_TLS_OFFSET);
6583             const elfcpp::Elf_Xword addend = rela.get_r_addend();
6584             gold_assert(addend == 0);
6585             got->add_static_reloc(got_offset,
6586                                   elfcpp::R_AARCH64_TLS_TPREL64, gsym);
6587           }
6588       }
6589       break;
6590
6591     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
6592     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
6593     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
6594     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
6595     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
6596     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
6597     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
6598     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:  // Local executable
6599       layout->set_has_static_tls();
6600       if (parameters->options().shared())
6601         gold_error(_("%s: unsupported TLSLE reloc type %u in shared objects."),
6602                    object->name().c_str(), r_type);
6603       break;
6604
6605     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
6606     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
6607     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:  // TLS descriptor
6608       {
6609         target->define_tls_base_symbol(symtab, layout);
6610         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6611             optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6612         if (tlsopt == tls::TLSOPT_NONE)
6613           {
6614             // Create reserved PLT and GOT entries for the resolver.
6615             target->reserve_tlsdesc_entries(symtab, layout);
6616
6617             // Create a double GOT entry with an R_AARCH64_TLSDESC
6618             // relocation. The R_AARCH64_TLSDESC is resolved lazily, so the GOT
6619             // entry needs to be in an area in .got.plt, not .got. Call
6620             // got_section to make sure the section has been created.
6621             target->got_section(symtab, layout);
6622             Output_data_got<size, big_endian>* got =
6623                 target->got_tlsdesc_section();
6624             Reloc_section* rt = target->rela_tlsdesc_section(layout);
6625             got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
6626                                           elfcpp::R_AARCH64_TLSDESC, 0);
6627           }
6628         else if (tlsopt == tls::TLSOPT_TO_IE)
6629           {
6630             // Create a GOT entry for the tp-relative offset.
6631             Output_data_got<size, big_endian>* got
6632                 = target->got_section(symtab, layout);
6633             got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
6634                                      target->rela_dyn_section(layout),
6635                                      elfcpp::R_AARCH64_TLS_TPREL64);
6636           }
6637         else if (tlsopt != tls::TLSOPT_TO_LE)
6638           unsupported_reloc_global(object, r_type, gsym);
6639       }
6640       break;
6641
6642     case elfcpp::R_AARCH64_TLSDESC_CALL:
6643       break;
6644
6645     default:
6646       gold_error(_("%s: unsupported reloc type in global scan"),
6647                  aarch64_reloc_property_table->
6648                  reloc_name_in_error_message(r_type).c_str());
6649     }
6650   return;
6651 }  // End of Scan::global
6652
6653
6654 // Create the PLT section.
6655 template<int size, bool big_endian>
6656 void
6657 Target_aarch64<size, big_endian>::make_plt_section(
6658   Symbol_table* symtab, Layout* layout)
6659 {
6660   if (this->plt_ == NULL)
6661     {
6662       // Create the GOT section first.
6663       this->got_section(symtab, layout);
6664
6665       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
6666                                        this->got_irelative_);
6667
6668       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
6669                                       (elfcpp::SHF_ALLOC
6670                                        | elfcpp::SHF_EXECINSTR),
6671                                       this->plt_, ORDER_PLT, false);
6672
6673       // Make the sh_info field of .rela.plt point to .plt.
6674       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
6675       rela_plt_os->set_info_section(this->plt_->output_section());
6676     }
6677 }
6678
6679 // Return the section for TLSDESC relocations.
6680
6681 template<int size, bool big_endian>
6682 typename Target_aarch64<size, big_endian>::Reloc_section*
6683 Target_aarch64<size, big_endian>::rela_tlsdesc_section(Layout* layout) const
6684 {
6685   return this->plt_section()->rela_tlsdesc(layout);
6686 }
6687
6688 // Create a PLT entry for a global symbol.
6689
6690 template<int size, bool big_endian>
6691 void
6692 Target_aarch64<size, big_endian>::make_plt_entry(
6693     Symbol_table* symtab,
6694     Layout* layout,
6695     Symbol* gsym)
6696 {
6697   if (gsym->has_plt_offset())
6698     return;
6699
6700   if (this->plt_ == NULL)
6701     this->make_plt_section(symtab, layout);
6702
6703   this->plt_->add_entry(symtab, layout, gsym);
6704 }
6705
6706 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
6707
6708 template<int size, bool big_endian>
6709 void
6710 Target_aarch64<size, big_endian>::make_local_ifunc_plt_entry(
6711     Symbol_table* symtab, Layout* layout,
6712     Sized_relobj_file<size, big_endian>* relobj,
6713     unsigned int local_sym_index)
6714 {
6715   if (relobj->local_has_plt_offset(local_sym_index))
6716     return;
6717   if (this->plt_ == NULL)
6718     this->make_plt_section(symtab, layout);
6719   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
6720                                                               relobj,
6721                                                               local_sym_index);
6722   relobj->set_local_plt_offset(local_sym_index, plt_offset);
6723 }
6724
6725 template<int size, bool big_endian>
6726 void
6727 Target_aarch64<size, big_endian>::gc_process_relocs(
6728     Symbol_table* symtab,
6729     Layout* layout,
6730     Sized_relobj_file<size, big_endian>* object,
6731     unsigned int data_shndx,
6732     unsigned int sh_type,
6733     const unsigned char* prelocs,
6734     size_t reloc_count,
6735     Output_section* output_section,
6736     bool needs_special_offset_handling,
6737     size_t local_symbol_count,
6738     const unsigned char* plocal_symbols)
6739 {
6740   typedef Target_aarch64<size, big_endian> Aarch64;
6741   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
6742       Classify_reloc;
6743
6744   if (sh_type == elfcpp::SHT_REL)
6745     {
6746       return;
6747     }
6748
6749   gold::gc_process_relocs<size, big_endian, Aarch64, Scan, Classify_reloc>(
6750     symtab,
6751     layout,
6752     this,
6753     object,
6754     data_shndx,
6755     prelocs,
6756     reloc_count,
6757     output_section,
6758     needs_special_offset_handling,
6759     local_symbol_count,
6760     plocal_symbols);
6761 }
6762
6763 // Scan relocations for a section.
6764
6765 template<int size, bool big_endian>
6766 void
6767 Target_aarch64<size, big_endian>::scan_relocs(
6768     Symbol_table* symtab,
6769     Layout* layout,
6770     Sized_relobj_file<size, big_endian>* object,
6771     unsigned int data_shndx,
6772     unsigned int sh_type,
6773     const unsigned char* prelocs,
6774     size_t reloc_count,
6775     Output_section* output_section,
6776     bool needs_special_offset_handling,
6777     size_t local_symbol_count,
6778     const unsigned char* plocal_symbols)
6779 {
6780   typedef Target_aarch64<size, big_endian> Aarch64;
6781   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
6782       Classify_reloc;
6783
6784   if (sh_type == elfcpp::SHT_REL)
6785     {
6786       gold_error(_("%s: unsupported REL reloc section"),
6787                  object->name().c_str());
6788       return;
6789     }
6790
6791   gold::scan_relocs<size, big_endian, Aarch64, Scan, Classify_reloc>(
6792     symtab,
6793     layout,
6794     this,
6795     object,
6796     data_shndx,
6797     prelocs,
6798     reloc_count,
6799     output_section,
6800     needs_special_offset_handling,
6801     local_symbol_count,
6802     plocal_symbols);
6803 }
6804
6805 // Return the value to use for a dynamic which requires special
6806 // treatment.  This is how we support equality comparisons of function
6807 // pointers across shared library boundaries, as described in the
6808 // processor specific ABI supplement.
6809
6810 template<int size, bool big_endian>
6811 uint64_t
6812 Target_aarch64<size, big_endian>::do_dynsym_value(const Symbol* gsym) const
6813 {
6814   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
6815   return this->plt_address_for_global(gsym);
6816 }
6817
6818
6819 // Finalize the sections.
6820
6821 template<int size, bool big_endian>
6822 void
6823 Target_aarch64<size, big_endian>::do_finalize_sections(
6824     Layout* layout,
6825     const Input_objects*,
6826     Symbol_table* symtab)
6827 {
6828   const Reloc_section* rel_plt = (this->plt_ == NULL
6829                                   ? NULL
6830                                   : this->plt_->rela_plt());
6831   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
6832                                   this->rela_dyn_, true, false);
6833
6834   // Emit any relocs we saved in an attempt to avoid generating COPY
6835   // relocs.
6836   if (this->copy_relocs_.any_saved_relocs())
6837     this->copy_relocs_.emit(this->rela_dyn_section(layout));
6838
6839   // Fill in some more dynamic tags.
6840   Output_data_dynamic* const odyn = layout->dynamic_data();
6841   if (odyn != NULL)
6842     {
6843       if (this->plt_ != NULL
6844           && this->plt_->output_section() != NULL
6845           && this->plt_ ->has_tlsdesc_entry())
6846         {
6847           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
6848           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
6849           this->got_->finalize_data_size();
6850           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
6851                                         this->plt_, plt_offset);
6852           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
6853                                         this->got_, got_offset);
6854         }
6855     }
6856
6857   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
6858   // the .got.plt section.
6859   Symbol* sym = this->global_offset_table_;
6860   if (sym != NULL)
6861     {
6862       uint64_t data_size = this->got_plt_->current_data_size();
6863       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
6864
6865       // If the .got section is more than 0x8000 bytes, we add
6866       // 0x8000 to the value of _GLOBAL_OFFSET_TABLE_, so that 16
6867       // bit relocations have a greater chance of working.
6868       if (data_size >= 0x8000)
6869         symtab->get_sized_symbol<size>(sym)->set_value(
6870           symtab->get_sized_symbol<size>(sym)->value() + 0x8000);
6871     }
6872
6873   if (parameters->doing_static_link()
6874       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
6875     {
6876       // If linking statically, make sure that the __rela_iplt symbols
6877       // were defined if necessary, even if we didn't create a PLT.
6878       static const Define_symbol_in_segment syms[] =
6879         {
6880           {
6881             "__rela_iplt_start",        // name
6882             elfcpp::PT_LOAD,            // segment_type
6883             elfcpp::PF_W,               // segment_flags_set
6884             elfcpp::PF(0),              // segment_flags_clear
6885             0,                          // value
6886             0,                          // size
6887             elfcpp::STT_NOTYPE,         // type
6888             elfcpp::STB_GLOBAL,         // binding
6889             elfcpp::STV_HIDDEN,         // visibility
6890             0,                          // nonvis
6891             Symbol::SEGMENT_START,      // offset_from_base
6892             true                        // only_if_ref
6893           },
6894           {
6895             "__rela_iplt_end",          // name
6896             elfcpp::PT_LOAD,            // segment_type
6897             elfcpp::PF_W,               // segment_flags_set
6898             elfcpp::PF(0),              // segment_flags_clear
6899             0,                          // value
6900             0,                          // size
6901             elfcpp::STT_NOTYPE,         // type
6902             elfcpp::STB_GLOBAL,         // binding
6903             elfcpp::STV_HIDDEN,         // visibility
6904             0,                          // nonvis
6905             Symbol::SEGMENT_START,      // offset_from_base
6906             true                        // only_if_ref
6907           }
6908         };
6909
6910       symtab->define_symbols(layout, 2, syms,
6911                              layout->script_options()->saw_sections_clause());
6912     }
6913
6914   return;
6915 }
6916
6917 // Perform a relocation.
6918
6919 template<int size, bool big_endian>
6920 inline bool
6921 Target_aarch64<size, big_endian>::Relocate::relocate(
6922     const Relocate_info<size, big_endian>* relinfo,
6923     unsigned int,
6924     Target_aarch64<size, big_endian>* target,
6925     Output_section* ,
6926     size_t relnum,
6927     const unsigned char* preloc,
6928     const Sized_symbol<size>* gsym,
6929     const Symbol_value<size>* psymval,
6930     unsigned char* view,
6931     typename elfcpp::Elf_types<size>::Elf_Addr address,
6932     section_size_type /* view_size */)
6933 {
6934   if (view == NULL)
6935     return true;
6936
6937   typedef AArch64_relocate_functions<size, big_endian> Reloc;
6938
6939   const elfcpp::Rela<size, big_endian> rela(preloc);
6940   unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
6941   const AArch64_reloc_property* reloc_property =
6942       aarch64_reloc_property_table->get_reloc_property(r_type);
6943
6944   if (reloc_property == NULL)
6945     {
6946       std::string reloc_name =
6947           aarch64_reloc_property_table->reloc_name_in_error_message(r_type);
6948       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
6949                              _("cannot relocate %s in object file"),
6950                              reloc_name.c_str());
6951       return true;
6952     }
6953
6954   const Sized_relobj_file<size, big_endian>* object = relinfo->object;
6955
6956   // Pick the value to use for symbols defined in the PLT.
6957   Symbol_value<size> symval;
6958   if (gsym != NULL
6959       && gsym->use_plt_offset(reloc_property->reference_flags()))
6960     {
6961       symval.set_output_value(target->plt_address_for_global(gsym));
6962       psymval = &symval;
6963     }
6964   else if (gsym == NULL && psymval->is_ifunc_symbol())
6965     {
6966       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
6967       if (object->local_has_plt_offset(r_sym))
6968         {
6969           symval.set_output_value(target->plt_address_for_local(object, r_sym));
6970           psymval = &symval;
6971         }
6972     }
6973
6974   const elfcpp::Elf_Xword addend = rela.get_r_addend();
6975
6976   // Get the GOT offset if needed.
6977   // For aarch64, the GOT pointer points to the start of the GOT section.
6978   bool have_got_offset = false;
6979   int got_offset = 0;
6980   int got_base = (target->got_ != NULL
6981                   ? (target->got_->current_data_size() >= 0x8000
6982                      ? 0x8000 : 0)
6983                   : 0);
6984   switch (r_type)
6985     {
6986     case elfcpp::R_AARCH64_MOVW_GOTOFF_G0:
6987     case elfcpp::R_AARCH64_MOVW_GOTOFF_G0_NC:
6988     case elfcpp::R_AARCH64_MOVW_GOTOFF_G1:
6989     case elfcpp::R_AARCH64_MOVW_GOTOFF_G1_NC:
6990     case elfcpp::R_AARCH64_MOVW_GOTOFF_G2:
6991     case elfcpp::R_AARCH64_MOVW_GOTOFF_G2_NC:
6992     case elfcpp::R_AARCH64_MOVW_GOTOFF_G3:
6993     case elfcpp::R_AARCH64_GOTREL64:
6994     case elfcpp::R_AARCH64_GOTREL32:
6995     case elfcpp::R_AARCH64_GOT_LD_PREL19:
6996     case elfcpp::R_AARCH64_LD64_GOTOFF_LO15:
6997     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
6998     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
6999     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
7000       if (gsym != NULL)
7001         {
7002           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
7003           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - got_base;
7004         }
7005       else
7006         {
7007           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7008           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
7009           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
7010                         - got_base);
7011         }
7012       have_got_offset = true;
7013       break;
7014
7015     default:
7016       break;
7017     }
7018
7019   typename Reloc::Status reloc_status = Reloc::STATUS_OKAY;
7020   typename elfcpp::Elf_types<size>::Elf_Addr value;
7021   switch (r_type)
7022     {
7023     case elfcpp::R_AARCH64_NONE:
7024       break;
7025
7026     case elfcpp::R_AARCH64_ABS64:
7027       if (!parameters->options().apply_dynamic_relocs()
7028           && parameters->options().output_is_position_independent()
7029           && gsym != NULL
7030           && gsym->needs_dynamic_reloc(reloc_property->reference_flags())
7031           && !gsym->can_use_relative_reloc(false))
7032         // We have generated an absolute dynamic relocation, so do not
7033         // apply the relocation statically. (Works around bugs in older
7034         // Android dynamic linkers.)
7035         break;
7036       reloc_status = Reloc::template rela_ua<64>(
7037         view, object, psymval, addend, reloc_property);
7038       break;
7039
7040     case elfcpp::R_AARCH64_ABS32:
7041       if (!parameters->options().apply_dynamic_relocs()
7042           && parameters->options().output_is_position_independent()
7043           && gsym != NULL
7044           && gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
7045         // We have generated an absolute dynamic relocation, so do not
7046         // apply the relocation statically. (Works around bugs in older
7047         // Android dynamic linkers.)
7048         break;
7049       reloc_status = Reloc::template rela_ua<32>(
7050         view, object, psymval, addend, reloc_property);
7051       break;
7052
7053     case elfcpp::R_AARCH64_ABS16:
7054       if (!parameters->options().apply_dynamic_relocs()
7055           && parameters->options().output_is_position_independent()
7056           && gsym != NULL
7057           && gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
7058         // We have generated an absolute dynamic relocation, so do not
7059         // apply the relocation statically. (Works around bugs in older
7060         // Android dynamic linkers.)
7061         break;
7062       reloc_status = Reloc::template rela_ua<16>(
7063         view, object, psymval, addend, reloc_property);
7064       break;
7065
7066     case elfcpp::R_AARCH64_PREL64:
7067       reloc_status = Reloc::template pcrela_ua<64>(
7068         view, object, psymval, addend, address, reloc_property);
7069       break;
7070
7071     case elfcpp::R_AARCH64_PREL32:
7072       reloc_status = Reloc::template pcrela_ua<32>(
7073         view, object, psymval, addend, address, reloc_property);
7074       break;
7075
7076     case elfcpp::R_AARCH64_PREL16:
7077       reloc_status = Reloc::template pcrela_ua<16>(
7078         view, object, psymval, addend, address, reloc_property);
7079       break;
7080
7081     case elfcpp::R_AARCH64_MOVW_UABS_G0:
7082     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:
7083     case elfcpp::R_AARCH64_MOVW_UABS_G1:
7084     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:
7085     case elfcpp::R_AARCH64_MOVW_UABS_G2:
7086     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:
7087     case elfcpp::R_AARCH64_MOVW_UABS_G3:
7088       reloc_status = Reloc::template rela_general<32>(
7089         view, object, psymval, addend, reloc_property);
7090       break;
7091     case elfcpp::R_AARCH64_MOVW_SABS_G0:
7092     case elfcpp::R_AARCH64_MOVW_SABS_G1:
7093     case elfcpp::R_AARCH64_MOVW_SABS_G2:
7094       reloc_status = Reloc::movnz(view, psymval->value(object, addend),
7095                                   reloc_property);
7096       break;
7097
7098     case elfcpp::R_AARCH64_LD_PREL_LO19:
7099       reloc_status = Reloc::template pcrela_general<32>(
7100           view, object, psymval, addend, address, reloc_property);
7101       break;
7102
7103     case elfcpp::R_AARCH64_ADR_PREL_LO21:
7104       reloc_status = Reloc::adr(view, object, psymval, addend,
7105                                 address, reloc_property);
7106       break;
7107
7108     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
7109     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
7110       reloc_status = Reloc::adrp(view, object, psymval, addend, address,
7111                                  reloc_property);
7112       break;
7113
7114     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:
7115     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:
7116     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:
7117     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:
7118     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC:
7119     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
7120       reloc_status = Reloc::template rela_general<32>(
7121         view, object, psymval, addend, reloc_property);
7122       break;
7123
7124     case elfcpp::R_AARCH64_CALL26:
7125       if (this->skip_call_tls_get_addr_)
7126         {
7127           // Double check that the TLSGD insn has been optimized away.
7128           typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7129           Insntype insn = elfcpp::Swap<32, big_endian>::readval(
7130               reinterpret_cast<Insntype*>(view));
7131           gold_assert((insn & 0xff000000) == 0x91000000);
7132
7133           reloc_status = Reloc::STATUS_OKAY;
7134           this->skip_call_tls_get_addr_ = false;
7135           // Return false to stop further processing this reloc.
7136           return false;
7137         }
7138       // Fall through.
7139     case elfcpp::R_AARCH64_JUMP26:
7140       if (Reloc::maybe_apply_stub(r_type, relinfo, rela, view, address,
7141                                   gsym, psymval, object,
7142                                   target->stub_group_size_))
7143         break;
7144       // Fall through.
7145     case elfcpp::R_AARCH64_TSTBR14:
7146     case elfcpp::R_AARCH64_CONDBR19:
7147       reloc_status = Reloc::template pcrela_general<32>(
7148         view, object, psymval, addend, address, reloc_property);
7149       break;
7150
7151     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
7152       gold_assert(have_got_offset);
7153       value = target->got_->address() + got_base + got_offset;
7154       reloc_status = Reloc::adrp(view, value + addend, address);
7155       break;
7156
7157     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
7158       gold_assert(have_got_offset);
7159       value = target->got_->address() + got_base + got_offset;
7160       reloc_status = Reloc::template rela_general<32>(
7161         view, value, addend, reloc_property);
7162       break;
7163
7164     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
7165       {
7166         gold_assert(have_got_offset);
7167         value = target->got_->address() + got_base + got_offset + addend -
7168           Reloc::Page(target->got_->address() + got_base);
7169         if ((value & 7) != 0)
7170           reloc_status = Reloc::STATUS_OVERFLOW;
7171         else
7172           reloc_status = Reloc::template reloc_common<32>(
7173             view, value, reloc_property);
7174         break;
7175       }
7176
7177     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7178     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
7179     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7180     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
7181     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7182     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7183     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7184     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
7185     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7186     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
7187     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7188     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7189     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
7190     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7191     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
7192     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
7193     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
7194     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
7195     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7196     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7197     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7198     case elfcpp::R_AARCH64_TLSDESC_CALL:
7199       reloc_status = relocate_tls(relinfo, target, relnum, rela, r_type,
7200                                   gsym, psymval, view, address);
7201       break;
7202
7203     // These are dynamic relocations, which are unexpected when linking.
7204     case elfcpp::R_AARCH64_COPY:
7205     case elfcpp::R_AARCH64_GLOB_DAT:
7206     case elfcpp::R_AARCH64_JUMP_SLOT:
7207     case elfcpp::R_AARCH64_RELATIVE:
7208     case elfcpp::R_AARCH64_IRELATIVE:
7209     case elfcpp::R_AARCH64_TLS_DTPREL64:
7210     case elfcpp::R_AARCH64_TLS_DTPMOD64:
7211     case elfcpp::R_AARCH64_TLS_TPREL64:
7212     case elfcpp::R_AARCH64_TLSDESC:
7213       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7214                              _("unexpected reloc %u in object file"),
7215                              r_type);
7216       break;
7217
7218     default:
7219       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7220                              _("unsupported reloc %s"),
7221                              reloc_property->name().c_str());
7222       break;
7223     }
7224
7225   // Report any errors.
7226   switch (reloc_status)
7227     {
7228     case Reloc::STATUS_OKAY:
7229       break;
7230     case Reloc::STATUS_OVERFLOW:
7231       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7232                              _("relocation overflow in %s"),
7233                              reloc_property->name().c_str());
7234       break;
7235     case Reloc::STATUS_BAD_RELOC:
7236       gold_error_at_location(
7237           relinfo,
7238           relnum,
7239           rela.get_r_offset(),
7240           _("unexpected opcode while processing relocation %s"),
7241           reloc_property->name().c_str());
7242       break;
7243     default:
7244       gold_unreachable();
7245     }
7246
7247   return true;
7248 }
7249
7250
7251 template<int size, bool big_endian>
7252 inline
7253 typename AArch64_relocate_functions<size, big_endian>::Status
7254 Target_aarch64<size, big_endian>::Relocate::relocate_tls(
7255     const Relocate_info<size, big_endian>* relinfo,
7256     Target_aarch64<size, big_endian>* target,
7257     size_t relnum,
7258     const elfcpp::Rela<size, big_endian>& rela,
7259     unsigned int r_type, const Sized_symbol<size>* gsym,
7260     const Symbol_value<size>* psymval,
7261     unsigned char* view,
7262     typename elfcpp::Elf_types<size>::Elf_Addr address)
7263 {
7264   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7265   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7266
7267   Output_segment* tls_segment = relinfo->layout->tls_segment();
7268   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7269   const AArch64_reloc_property* reloc_property =
7270       aarch64_reloc_property_table->get_reloc_property(r_type);
7271   gold_assert(reloc_property != NULL);
7272
7273   const bool is_final = (gsym == NULL
7274                          ? !parameters->options().shared()
7275                          : gsym->final_value_is_known());
7276   tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
7277       optimize_tls_reloc(is_final, r_type);
7278
7279   Sized_relobj_file<size, big_endian>* object = relinfo->object;
7280   int tls_got_offset_type;
7281   switch (r_type)
7282     {
7283     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7284     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:  // Global-dynamic
7285       {
7286         if (tlsopt == tls::TLSOPT_TO_LE)
7287           {
7288             if (tls_segment == NULL)
7289               {
7290                 gold_assert(parameters->errors()->error_count() > 0
7291                             || issue_undefined_symbol_error(gsym));
7292                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7293               }
7294             return tls_gd_to_le(relinfo, target, rela, r_type, view,
7295                                 psymval);
7296           }
7297         else if (tlsopt == tls::TLSOPT_NONE)
7298           {
7299             tls_got_offset_type = GOT_TYPE_TLS_PAIR;
7300             // Firstly get the address for the got entry.
7301             typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7302             if (gsym != NULL)
7303               {
7304                 gold_assert(gsym->has_got_offset(tls_got_offset_type));
7305                 got_entry_address = target->got_->address() +
7306                                     gsym->got_offset(tls_got_offset_type);
7307               }
7308             else
7309               {
7310                 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7311                 gold_assert(
7312                   object->local_has_got_offset(r_sym, tls_got_offset_type));
7313                 got_entry_address = target->got_->address() +
7314                   object->local_got_offset(r_sym, tls_got_offset_type);
7315               }
7316
7317             // Relocate the address into adrp/ld, adrp/add pair.
7318             switch (r_type)
7319               {
7320               case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7321                 return aarch64_reloc_funcs::adrp(
7322                   view, got_entry_address + addend, address);
7323
7324                 break;
7325
7326               case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
7327                 return aarch64_reloc_funcs::template rela_general<32>(
7328                   view, got_entry_address, addend, reloc_property);
7329                 break;
7330
7331               default:
7332                 gold_unreachable();
7333               }
7334           }
7335         gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7336                                _("unsupported gd_to_ie relaxation on %u"),
7337                                r_type);
7338       }
7339       break;
7340
7341     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7342     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:  // Local-dynamic
7343       {
7344         if (tlsopt == tls::TLSOPT_TO_LE)
7345           {
7346             if (tls_segment == NULL)
7347               {
7348                 gold_assert(parameters->errors()->error_count() > 0
7349                             || issue_undefined_symbol_error(gsym));
7350                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7351               }
7352             return this->tls_ld_to_le(relinfo, target, rela, r_type, view,
7353                                       psymval);
7354           }
7355
7356         gold_assert(tlsopt == tls::TLSOPT_NONE);
7357         // Relocate the field with the offset of the GOT entry for
7358         // the module index.
7359         typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7360         got_entry_address = (target->got_mod_index_entry(NULL, NULL, NULL) +
7361                              target->got_->address());
7362
7363         switch (r_type)
7364           {
7365           case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7366             return aarch64_reloc_funcs::adrp(
7367               view, got_entry_address + addend, address);
7368             break;
7369
7370           case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
7371             return aarch64_reloc_funcs::template rela_general<32>(
7372               view, got_entry_address, addend, reloc_property);
7373             break;
7374
7375           default:
7376             gold_unreachable();
7377           }
7378       }
7379       break;
7380
7381     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7382     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7383     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7384     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:  // Other local-dynamic
7385       {
7386         AArch64_address value = psymval->value(object, 0);
7387         if (tlsopt == tls::TLSOPT_TO_LE)
7388           {
7389             if (tls_segment == NULL)
7390               {
7391                 gold_assert(parameters->errors()->error_count() > 0
7392                             || issue_undefined_symbol_error(gsym));
7393                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7394               }
7395           }
7396         switch (r_type)
7397           {
7398           case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7399             return aarch64_reloc_funcs::movnz(view, value + addend,
7400                                               reloc_property);
7401             break;
7402
7403           case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7404           case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7405           case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
7406             return aarch64_reloc_funcs::template rela_general<32>(
7407                 view, value, addend, reloc_property);
7408             break;
7409
7410           default:
7411             gold_unreachable();
7412           }
7413         // We should never reach here.
7414       }
7415       break;
7416
7417     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7418     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:  // Initial-exec
7419       {
7420         if (tlsopt == tls::TLSOPT_TO_LE)
7421           {
7422             if (tls_segment == NULL)
7423               {
7424                 gold_assert(parameters->errors()->error_count() > 0
7425                             || issue_undefined_symbol_error(gsym));
7426                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7427               }
7428             return tls_ie_to_le(relinfo, target, rela, r_type, view,
7429                                 psymval);
7430           }
7431         tls_got_offset_type = GOT_TYPE_TLS_OFFSET;
7432
7433         // Firstly get the address for the got entry.
7434         typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7435         if (gsym != NULL)
7436           {
7437             gold_assert(gsym->has_got_offset(tls_got_offset_type));
7438             got_entry_address = target->got_->address() +
7439                                 gsym->got_offset(tls_got_offset_type);
7440           }
7441         else
7442           {
7443             unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7444             gold_assert(
7445                 object->local_has_got_offset(r_sym, tls_got_offset_type));
7446             got_entry_address = target->got_->address() +
7447                 object->local_got_offset(r_sym, tls_got_offset_type);
7448           }
7449         // Relocate the address into adrp/ld, adrp/add pair.
7450         switch (r_type)
7451           {
7452           case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7453             return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
7454                                              address);
7455             break;
7456           case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
7457             return aarch64_reloc_funcs::template rela_general<32>(
7458               view, got_entry_address, addend, reloc_property);
7459           default:
7460             gold_unreachable();
7461           }
7462       }
7463       // We shall never reach here.
7464       break;
7465
7466     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7467     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7468     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
7469     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7470     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
7471     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
7472     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
7473     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
7474       {
7475         gold_assert(tls_segment != NULL);
7476         AArch64_address value = psymval->value(object, 0);
7477
7478         if (!parameters->options().shared())
7479           {
7480             AArch64_address aligned_tcb_size =
7481                 align_address(target->tcb_size(),
7482                               tls_segment->maximum_alignment());
7483             value += aligned_tcb_size;
7484             switch (r_type)
7485               {
7486               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7487               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7488               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7489                 return aarch64_reloc_funcs::movnz(view, value + addend,
7490                                                   reloc_property);
7491               default:
7492                 return aarch64_reloc_funcs::template
7493                   rela_general<32>(view,
7494                                    value,
7495                                    addend,
7496                                    reloc_property);
7497               }
7498           }
7499         else
7500           gold_error(_("%s: unsupported reloc %u "
7501                        "in non-static TLSLE mode."),
7502                      object->name().c_str(), r_type);
7503       }
7504       break;
7505
7506     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7507     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7508     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7509     case elfcpp::R_AARCH64_TLSDESC_CALL:
7510       {
7511         if (tlsopt == tls::TLSOPT_TO_LE)
7512           {
7513             if (tls_segment == NULL)
7514               {
7515                 gold_assert(parameters->errors()->error_count() > 0
7516                             || issue_undefined_symbol_error(gsym));
7517                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7518               }
7519             return tls_desc_gd_to_le(relinfo, target, rela, r_type,
7520                                      view, psymval);
7521           }
7522         else
7523           {
7524             tls_got_offset_type = (tlsopt == tls::TLSOPT_TO_IE
7525                                    ? GOT_TYPE_TLS_OFFSET
7526                                    : GOT_TYPE_TLS_DESC);
7527             unsigned int got_tlsdesc_offset = 0;
7528             if (r_type != elfcpp::R_AARCH64_TLSDESC_CALL
7529                 && tlsopt == tls::TLSOPT_NONE)
7530               {
7531                 // We created GOT entries in the .got.tlsdesc portion of the
7532                 // .got.plt section, but the offset stored in the symbol is the
7533                 // offset within .got.tlsdesc.
7534                 got_tlsdesc_offset = (target->got_->data_size()
7535                                       + target->got_plt_section()->data_size());
7536               }
7537             typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7538             if (gsym != NULL)
7539               {
7540                 gold_assert(gsym->has_got_offset(tls_got_offset_type));
7541                 got_entry_address = target->got_->address()
7542                                     + got_tlsdesc_offset
7543                                     + gsym->got_offset(tls_got_offset_type);
7544               }
7545             else
7546               {
7547                 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7548                 gold_assert(
7549                     object->local_has_got_offset(r_sym, tls_got_offset_type));
7550                 got_entry_address = target->got_->address() +
7551                   got_tlsdesc_offset +
7552                   object->local_got_offset(r_sym, tls_got_offset_type);
7553               }
7554             if (tlsopt == tls::TLSOPT_TO_IE)
7555               {
7556                 return tls_desc_gd_to_ie(relinfo, target, rela, r_type,
7557                                          view, psymval, got_entry_address,
7558                                          address);
7559               }
7560
7561             // Now do tlsdesc relocation.
7562             switch (r_type)
7563               {
7564               case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7565                 return aarch64_reloc_funcs::adrp(view,
7566                                                  got_entry_address + addend,
7567                                                  address);
7568                 break;
7569               case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7570               case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7571                 return aarch64_reloc_funcs::template rela_general<32>(
7572                   view, got_entry_address, addend, reloc_property);
7573                 break;
7574               case elfcpp::R_AARCH64_TLSDESC_CALL:
7575                 return aarch64_reloc_funcs::STATUS_OKAY;
7576                 break;
7577               default:
7578                 gold_unreachable();
7579               }
7580           }
7581         }
7582       break;
7583
7584     default:
7585       gold_error(_("%s: unsupported TLS reloc %u."),
7586                  object->name().c_str(), r_type);
7587     }
7588   return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7589 }  // End of relocate_tls.
7590
7591
7592 template<int size, bool big_endian>
7593 inline
7594 typename AArch64_relocate_functions<size, big_endian>::Status
7595 Target_aarch64<size, big_endian>::Relocate::tls_gd_to_le(
7596              const Relocate_info<size, big_endian>* relinfo,
7597              Target_aarch64<size, big_endian>* target,
7598              const elfcpp::Rela<size, big_endian>& rela,
7599              unsigned int r_type,
7600              unsigned char* view,
7601              const Symbol_value<size>* psymval)
7602 {
7603   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7604   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7605   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7606
7607   Insntype* ip = reinterpret_cast<Insntype*>(view);
7608   Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
7609   Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
7610   Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
7611
7612   if (r_type == elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC)
7613     {
7614       // This is the 2nd relocs, optimization should already have been
7615       // done.
7616       gold_assert((insn1 & 0xfff00000) == 0x91400000);
7617       return aarch64_reloc_funcs::STATUS_OKAY;
7618     }
7619
7620   // The original sequence is -
7621   //   90000000        adrp    x0, 0 <main>
7622   //   91000000        add     x0, x0, #0x0
7623   //   94000000        bl      0 <__tls_get_addr>
7624   // optimized to sequence -
7625   //   d53bd040        mrs     x0, tpidr_el0
7626   //   91400000        add     x0, x0, #0x0, lsl #12
7627   //   91000000        add     x0, x0, #0x0
7628
7629   // Unlike tls_ie_to_le, we change the 3 insns in one function call when we
7630   // encounter the first relocation "R_AARCH64_TLSGD_ADR_PAGE21". Because we
7631   // have to change "bl tls_get_addr", which does not have a corresponding tls
7632   // relocation type. So before proceeding, we need to make sure compiler
7633   // does not change the sequence.
7634   if(!(insn1 == 0x90000000      // adrp x0,0
7635        && insn2 == 0x91000000   // add x0, x0, #0x0
7636        && insn3 == 0x94000000)) // bl 0
7637     {
7638       // Ideally we should give up gd_to_le relaxation and do gd access.
7639       // However the gd_to_le relaxation decision has been made early
7640       // in the scan stage, where we did not allocate any GOT entry for
7641       // this symbol. Therefore we have to exit and report error now.
7642       gold_error(_("unexpected reloc insn sequence while relaxing "
7643                    "tls gd to le for reloc %u."), r_type);
7644       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7645     }
7646
7647   // Write new insns.
7648   insn1 = 0xd53bd040;  // mrs x0, tpidr_el0
7649   insn2 = 0x91400000;  // add x0, x0, #0x0, lsl #12
7650   insn3 = 0x91000000;  // add x0, x0, #0x0
7651   elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
7652   elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
7653   elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
7654
7655   // Calculate tprel value.
7656   Output_segment* tls_segment = relinfo->layout->tls_segment();
7657   gold_assert(tls_segment != NULL);
7658   AArch64_address value = psymval->value(relinfo->object, 0);
7659   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7660   AArch64_address aligned_tcb_size =
7661       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7662   AArch64_address x = value + aligned_tcb_size;
7663
7664   // After new insns are written, apply TLSLE relocs.
7665   const AArch64_reloc_property* rp1 =
7666       aarch64_reloc_property_table->get_reloc_property(
7667           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
7668   const AArch64_reloc_property* rp2 =
7669       aarch64_reloc_property_table->get_reloc_property(
7670           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
7671   gold_assert(rp1 != NULL && rp2 != NULL);
7672
7673   typename aarch64_reloc_funcs::Status s1 =
7674       aarch64_reloc_funcs::template rela_general<32>(view + 4,
7675                                                      x,
7676                                                      addend,
7677                                                      rp1);
7678   if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
7679     return s1;
7680
7681   typename aarch64_reloc_funcs::Status s2 =
7682       aarch64_reloc_funcs::template rela_general<32>(view + 8,
7683                                                      x,
7684                                                      addend,
7685                                                      rp2);
7686
7687   this->skip_call_tls_get_addr_ = true;
7688   return s2;
7689 }  // End of tls_gd_to_le
7690
7691
7692 template<int size, bool big_endian>
7693 inline
7694 typename AArch64_relocate_functions<size, big_endian>::Status
7695 Target_aarch64<size, big_endian>::Relocate::tls_ld_to_le(
7696              const Relocate_info<size, big_endian>* relinfo,
7697              Target_aarch64<size, big_endian>* target,
7698              const elfcpp::Rela<size, big_endian>& rela,
7699              unsigned int r_type,
7700              unsigned char* view,
7701              const Symbol_value<size>* psymval)
7702 {
7703   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7704   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7705   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7706
7707   Insntype* ip = reinterpret_cast<Insntype*>(view);
7708   Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
7709   Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
7710   Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
7711
7712   if (r_type == elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC)
7713     {
7714       // This is the 2nd relocs, optimization should already have been
7715       // done.
7716       gold_assert((insn1 & 0xfff00000) == 0x91400000);
7717       return aarch64_reloc_funcs::STATUS_OKAY;
7718     }
7719
7720   // The original sequence is -
7721   //   90000000        adrp    x0, 0 <main>
7722   //   91000000        add     x0, x0, #0x0
7723   //   94000000        bl      0 <__tls_get_addr>
7724   // optimized to sequence -
7725   //   d53bd040        mrs     x0, tpidr_el0
7726   //   91400000        add     x0, x0, #0x0, lsl #12
7727   //   91000000        add     x0, x0, #0x0
7728
7729   // Unlike tls_ie_to_le, we change the 3 insns in one function call when we
7730   // encounter the first relocation "R_AARCH64_TLSLD_ADR_PAGE21". Because we
7731   // have to change "bl tls_get_addr", which does not have a corresponding tls
7732   // relocation type. So before proceeding, we need to make sure compiler
7733   // does not change the sequence.
7734   if(!(insn1 == 0x90000000      // adrp x0,0
7735        && insn2 == 0x91000000   // add x0, x0, #0x0
7736        && insn3 == 0x94000000)) // bl 0
7737     {
7738       // Ideally we should give up gd_to_le relaxation and do gd access.
7739       // However the gd_to_le relaxation decision has been made early
7740       // in the scan stage, where we did not allocate a GOT entry for
7741       // this symbol. Therefore we have to exit and report an error now.
7742       gold_error(_("unexpected reloc insn sequence while relaxing "
7743                    "tls gd to le for reloc %u."), r_type);
7744       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7745     }
7746
7747   // Write new insns.
7748   insn1 = 0xd53bd040;  // mrs x0, tpidr_el0
7749   insn2 = 0x91400000;  // add x0, x0, #0x0, lsl #12
7750   insn3 = 0x91000000;  // add x0, x0, #0x0
7751   elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
7752   elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
7753   elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
7754
7755   // Calculate tprel value.
7756   Output_segment* tls_segment = relinfo->layout->tls_segment();
7757   gold_assert(tls_segment != NULL);
7758   AArch64_address value = psymval->value(relinfo->object, 0);
7759   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7760   AArch64_address aligned_tcb_size =
7761       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7762   AArch64_address x = value + aligned_tcb_size;
7763
7764   // After new insns are written, apply TLSLE relocs.
7765   const AArch64_reloc_property* rp1 =
7766       aarch64_reloc_property_table->get_reloc_property(
7767           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
7768   const AArch64_reloc_property* rp2 =
7769       aarch64_reloc_property_table->get_reloc_property(
7770           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
7771   gold_assert(rp1 != NULL && rp2 != NULL);
7772
7773   typename aarch64_reloc_funcs::Status s1 =
7774       aarch64_reloc_funcs::template rela_general<32>(view + 4,
7775                                                      x,
7776                                                      addend,
7777                                                      rp1);
7778   if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
7779     return s1;
7780
7781   typename aarch64_reloc_funcs::Status s2 =
7782       aarch64_reloc_funcs::template rela_general<32>(view + 8,
7783                                                      x,
7784                                                      addend,
7785                                                      rp2);
7786
7787   this->skip_call_tls_get_addr_ = true;
7788   return s2;
7789
7790 }  // End of tls_ld_to_le
7791
7792 template<int size, bool big_endian>
7793 inline
7794 typename AArch64_relocate_functions<size, big_endian>::Status
7795 Target_aarch64<size, big_endian>::Relocate::tls_ie_to_le(
7796              const Relocate_info<size, big_endian>* relinfo,
7797              Target_aarch64<size, big_endian>* target,
7798              const elfcpp::Rela<size, big_endian>& rela,
7799              unsigned int r_type,
7800              unsigned char* view,
7801              const Symbol_value<size>* psymval)
7802 {
7803   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7804   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7805   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7806
7807   AArch64_address value = psymval->value(relinfo->object, 0);
7808   Output_segment* tls_segment = relinfo->layout->tls_segment();
7809   AArch64_address aligned_tcb_address =
7810       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7811   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7812   AArch64_address x = value + addend + aligned_tcb_address;
7813   // "x" is the offset to tp, we can only do this if x is within
7814   // range [0, 2^32-1]
7815   if (!(size == 32 || (size == 64 && (static_cast<uint64_t>(x) >> 32) == 0)))
7816     {
7817       gold_error(_("TLS variable referred by reloc %u is too far from TP."),
7818                  r_type);
7819       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7820     }
7821
7822   Insntype* ip = reinterpret_cast<Insntype*>(view);
7823   Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
7824   unsigned int regno;
7825   Insntype newinsn;
7826   if (r_type == elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21)
7827     {
7828       // Generate movz.
7829       regno = (insn & 0x1f);
7830       newinsn = (0xd2a00000 | regno) | (((x >> 16) & 0xffff) << 5);
7831     }
7832   else if (r_type == elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC)
7833     {
7834       // Generate movk.
7835       regno = (insn & 0x1f);
7836       gold_assert(regno == ((insn >> 5) & 0x1f));
7837       newinsn = (0xf2800000 | regno) | ((x & 0xffff) << 5);
7838     }
7839   else
7840     gold_unreachable();
7841
7842   elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
7843   return aarch64_reloc_funcs::STATUS_OKAY;
7844 }  // End of tls_ie_to_le
7845
7846
7847 template<int size, bool big_endian>
7848 inline
7849 typename AArch64_relocate_functions<size, big_endian>::Status
7850 Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_le(
7851              const Relocate_info<size, big_endian>* relinfo,
7852              Target_aarch64<size, big_endian>* target,
7853              const elfcpp::Rela<size, big_endian>& rela,
7854              unsigned int r_type,
7855              unsigned char* view,
7856              const Symbol_value<size>* psymval)
7857 {
7858   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7859   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7860   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7861
7862   // TLSDESC-GD sequence is like:
7863   //   adrp  x0, :tlsdesc:v1
7864   //   ldr   x1, [x0, #:tlsdesc_lo12:v1]
7865   //   add   x0, x0, :tlsdesc_lo12:v1
7866   //   .tlsdesccall    v1
7867   //   blr   x1
7868   // After desc_gd_to_le optimization, the sequence will be like:
7869   //   movz  x0, #0x0, lsl #16
7870   //   movk  x0, #0x10
7871   //   nop
7872   //   nop
7873
7874   // Calculate tprel value.
7875   Output_segment* tls_segment = relinfo->layout->tls_segment();
7876   gold_assert(tls_segment != NULL);
7877   Insntype* ip = reinterpret_cast<Insntype*>(view);
7878   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7879   AArch64_address value = psymval->value(relinfo->object, addend);
7880   AArch64_address aligned_tcb_size =
7881       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7882   AArch64_address x = value + aligned_tcb_size;
7883   // x is the offset to tp, we can only do this if x is within range
7884   // [0, 2^32-1]. If x is out of range, fail and exit.
7885   if (size == 64 && (static_cast<uint64_t>(x) >> 32) != 0)
7886     {
7887       gold_error(_("TLS variable referred by reloc %u is too far from TP. "
7888                    "We Can't do gd_to_le relaxation.\n"), r_type);
7889       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7890     }
7891   Insntype newinsn;
7892   switch (r_type)
7893     {
7894     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7895     case elfcpp::R_AARCH64_TLSDESC_CALL:
7896       // Change to nop
7897       newinsn = 0xd503201f;
7898       break;
7899
7900     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7901       // Change to movz.
7902       newinsn = 0xd2a00000 | (((x >> 16) & 0xffff) << 5);
7903       break;
7904
7905     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7906       // Change to movk.
7907       newinsn = 0xf2800000 | ((x & 0xffff) << 5);
7908       break;
7909
7910     default:
7911       gold_error(_("unsupported tlsdesc gd_to_le optimization on reloc %u"),
7912                  r_type);
7913       gold_unreachable();
7914     }
7915   elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
7916   return aarch64_reloc_funcs::STATUS_OKAY;
7917 }  // End of tls_desc_gd_to_le
7918
7919
7920 template<int size, bool big_endian>
7921 inline
7922 typename AArch64_relocate_functions<size, big_endian>::Status
7923 Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_ie(
7924              const Relocate_info<size, big_endian>* /* relinfo */,
7925              Target_aarch64<size, big_endian>* /* target */,
7926              const elfcpp::Rela<size, big_endian>& rela,
7927              unsigned int r_type,
7928              unsigned char* view,
7929              const Symbol_value<size>* /* psymval */,
7930              typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address,
7931              typename elfcpp::Elf_types<size>::Elf_Addr address)
7932 {
7933   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7934   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7935
7936   // TLSDESC-GD sequence is like:
7937   //   adrp  x0, :tlsdesc:v1
7938   //   ldr   x1, [x0, #:tlsdesc_lo12:v1]
7939   //   add   x0, x0, :tlsdesc_lo12:v1
7940   //   .tlsdesccall    v1
7941   //   blr   x1
7942   // After desc_gd_to_ie optimization, the sequence will be like:
7943   //   adrp  x0, :tlsie:v1
7944   //   ldr   x0, [x0, :tlsie_lo12:v1]
7945   //   nop
7946   //   nop
7947
7948   Insntype* ip = reinterpret_cast<Insntype*>(view);
7949   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7950   Insntype newinsn;
7951   switch (r_type)
7952     {
7953     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7954     case elfcpp::R_AARCH64_TLSDESC_CALL:
7955       // Change to nop
7956       newinsn = 0xd503201f;
7957       elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
7958       break;
7959
7960     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7961       {
7962         return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
7963                                          address);
7964       }
7965       break;
7966
7967     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7968       {
7969        // Set ldr target register to be x0.
7970        Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
7971        insn &= 0xffffffe0;
7972        elfcpp::Swap<32, big_endian>::writeval(ip, insn);
7973        // Do relocation.
7974         const AArch64_reloc_property* reloc_property =
7975             aarch64_reloc_property_table->get_reloc_property(
7976               elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC);
7977         return aarch64_reloc_funcs::template rela_general<32>(
7978                  view, got_entry_address, addend, reloc_property);
7979       }
7980       break;
7981
7982     default:
7983       gold_error(_("Don't support tlsdesc gd_to_ie optimization on reloc %u"),
7984                  r_type);
7985       gold_unreachable();
7986     }
7987   return aarch64_reloc_funcs::STATUS_OKAY;
7988 }  // End of tls_desc_gd_to_ie
7989
7990 // Relocate section data.
7991
7992 template<int size, bool big_endian>
7993 void
7994 Target_aarch64<size, big_endian>::relocate_section(
7995     const Relocate_info<size, big_endian>* relinfo,
7996     unsigned int sh_type,
7997     const unsigned char* prelocs,
7998     size_t reloc_count,
7999     Output_section* output_section,
8000     bool needs_special_offset_handling,
8001     unsigned char* view,
8002     typename elfcpp::Elf_types<size>::Elf_Addr address,
8003     section_size_type view_size,
8004     const Reloc_symbol_changes* reloc_symbol_changes)
8005 {
8006   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
8007   typedef Target_aarch64<size, big_endian> Aarch64;
8008   typedef typename Target_aarch64<size, big_endian>::Relocate AArch64_relocate;
8009   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8010       Classify_reloc;
8011
8012   gold_assert(sh_type == elfcpp::SHT_RELA);
8013
8014   // See if we are relocating a relaxed input section.  If so, the view
8015   // covers the whole output section and we need to adjust accordingly.
8016   if (needs_special_offset_handling)
8017     {
8018       const Output_relaxed_input_section* poris =
8019         output_section->find_relaxed_input_section(relinfo->object,
8020                                                    relinfo->data_shndx);
8021       if (poris != NULL)
8022         {
8023           Address section_address = poris->address();
8024           section_size_type section_size = poris->data_size();
8025
8026           gold_assert((section_address >= address)
8027                       && ((section_address + section_size)
8028                           <= (address + view_size)));
8029
8030           off_t offset = section_address - address;
8031           view += offset;
8032           address += offset;
8033           view_size = section_size;
8034         }
8035     }
8036
8037   gold::relocate_section<size, big_endian, Aarch64, AArch64_relocate,
8038                          gold::Default_comdat_behavior, Classify_reloc>(
8039     relinfo,
8040     this,
8041     prelocs,
8042     reloc_count,
8043     output_section,
8044     needs_special_offset_handling,
8045     view,
8046     address,
8047     view_size,
8048     reloc_symbol_changes);
8049 }
8050
8051 // Scan the relocs during a relocatable link.
8052
8053 template<int size, bool big_endian>
8054 void
8055 Target_aarch64<size, big_endian>::scan_relocatable_relocs(
8056     Symbol_table* symtab,
8057     Layout* layout,
8058     Sized_relobj_file<size, big_endian>* object,
8059     unsigned int data_shndx,
8060     unsigned int sh_type,
8061     const unsigned char* prelocs,
8062     size_t reloc_count,
8063     Output_section* output_section,
8064     bool needs_special_offset_handling,
8065     size_t local_symbol_count,
8066     const unsigned char* plocal_symbols,
8067     Relocatable_relocs* rr)
8068 {
8069   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8070       Classify_reloc;
8071   typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
8072       Scan_relocatable_relocs;
8073
8074   gold_assert(sh_type == elfcpp::SHT_RELA);
8075
8076   gold::scan_relocatable_relocs<size, big_endian, Scan_relocatable_relocs>(
8077     symtab,
8078     layout,
8079     object,
8080     data_shndx,
8081     prelocs,
8082     reloc_count,
8083     output_section,
8084     needs_special_offset_handling,
8085     local_symbol_count,
8086     plocal_symbols,
8087     rr);
8088 }
8089
8090 // Scan the relocs for --emit-relocs.
8091
8092 template<int size, bool big_endian>
8093 void
8094 Target_aarch64<size, big_endian>::emit_relocs_scan(
8095     Symbol_table* symtab,
8096     Layout* layout,
8097     Sized_relobj_file<size, big_endian>* object,
8098     unsigned int data_shndx,
8099     unsigned int sh_type,
8100     const unsigned char* prelocs,
8101     size_t reloc_count,
8102     Output_section* output_section,
8103     bool needs_special_offset_handling,
8104     size_t local_symbol_count,
8105     const unsigned char* plocal_syms,
8106     Relocatable_relocs* rr)
8107 {
8108   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8109       Classify_reloc;
8110   typedef gold::Default_emit_relocs_strategy<Classify_reloc>
8111       Emit_relocs_strategy;
8112
8113   gold_assert(sh_type == elfcpp::SHT_RELA);
8114
8115   gold::scan_relocatable_relocs<size, big_endian, Emit_relocs_strategy>(
8116     symtab,
8117     layout,
8118     object,
8119     data_shndx,
8120     prelocs,
8121     reloc_count,
8122     output_section,
8123     needs_special_offset_handling,
8124     local_symbol_count,
8125     plocal_syms,
8126     rr);
8127 }
8128
8129 // Relocate a section during a relocatable link.
8130
8131 template<int size, bool big_endian>
8132 void
8133 Target_aarch64<size, big_endian>::relocate_relocs(
8134     const Relocate_info<size, big_endian>* relinfo,
8135     unsigned int sh_type,
8136     const unsigned char* prelocs,
8137     size_t reloc_count,
8138     Output_section* output_section,
8139     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
8140     unsigned char* view,
8141     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
8142     section_size_type view_size,
8143     unsigned char* reloc_view,
8144     section_size_type reloc_view_size)
8145 {
8146   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8147       Classify_reloc;
8148
8149   gold_assert(sh_type == elfcpp::SHT_RELA);
8150
8151   gold::relocate_relocs<size, big_endian, Classify_reloc>(
8152     relinfo,
8153     prelocs,
8154     reloc_count,
8155     output_section,
8156     offset_in_output_section,
8157     view,
8158     view_address,
8159     view_size,
8160     reloc_view,
8161     reloc_view_size);
8162 }
8163
8164
8165 // Return whether this is a 3-insn erratum sequence.
8166
8167 template<int size, bool big_endian>
8168 bool
8169 Target_aarch64<size, big_endian>::is_erratum_843419_sequence(
8170     typename elfcpp::Swap<32,big_endian>::Valtype insn1,
8171     typename elfcpp::Swap<32,big_endian>::Valtype insn2,
8172     typename elfcpp::Swap<32,big_endian>::Valtype insn3)
8173 {
8174   unsigned rt1, rt2;
8175   bool load, pair;
8176
8177   // The 2nd insn is a single register load or store; or register pair
8178   // store.
8179   if (Insn_utilities::aarch64_mem_op_p(insn2, &rt1, &rt2, &pair, &load)
8180       && (!pair || (pair && !load)))
8181     {
8182       // The 3rd insn is a load or store instruction from the "Load/store
8183       // register (unsigned immediate)" encoding class, using Rn as the
8184       // base address register.
8185       if (Insn_utilities::aarch64_ldst_uimm(insn3)
8186           && (Insn_utilities::aarch64_rn(insn3)
8187               == Insn_utilities::aarch64_rd(insn1)))
8188         return true;
8189     }
8190   return false;
8191 }
8192
8193
8194 // Return whether this is a 835769 sequence.
8195 // (Similarly implemented as in elfnn-aarch64.c.)
8196
8197 template<int size, bool big_endian>
8198 bool
8199 Target_aarch64<size, big_endian>::is_erratum_835769_sequence(
8200     typename elfcpp::Swap<32,big_endian>::Valtype insn1,
8201     typename elfcpp::Swap<32,big_endian>::Valtype insn2)
8202 {
8203   uint32_t rt;
8204   uint32_t rt2 = 0;
8205   uint32_t rn;
8206   uint32_t rm;
8207   uint32_t ra;
8208   bool pair;
8209   bool load;
8210
8211   if (Insn_utilities::aarch64_mlxl(insn2)
8212       && Insn_utilities::aarch64_mem_op_p (insn1, &rt, &rt2, &pair, &load))
8213     {
8214       /* Any SIMD memory op is independent of the subsequent MLA
8215          by definition of the erratum.  */
8216       if (Insn_utilities::aarch64_bit(insn1, 26))
8217         return true;
8218
8219       /* If not SIMD, check for integer memory ops and MLA relationship.  */
8220       rn = Insn_utilities::aarch64_rn(insn2);
8221       ra = Insn_utilities::aarch64_ra(insn2);
8222       rm = Insn_utilities::aarch64_rm(insn2);
8223
8224       /* If this is a load and there's a true(RAW) dependency, we are safe
8225          and this is not an erratum sequence.  */
8226       if (load &&
8227           (rt == rn || rt == rm || rt == ra
8228            || (pair && (rt2 == rn || rt2 == rm || rt2 == ra))))
8229         return false;
8230
8231       /* We conservatively put out stubs for all other cases (including
8232          writebacks).  */
8233       return true;
8234     }
8235
8236   return false;
8237 }
8238
8239
8240 // Helper method to create erratum stub for ST_E_843419 and ST_E_835769.
8241
8242 template<int size, bool big_endian>
8243 void
8244 Target_aarch64<size, big_endian>::create_erratum_stub(
8245     AArch64_relobj<size, big_endian>* relobj,
8246     unsigned int shndx,
8247     section_size_type erratum_insn_offset,
8248     Address erratum_address,
8249     typename Insn_utilities::Insntype erratum_insn,
8250     int erratum_type,
8251     unsigned int e843419_adrp_offset)
8252 {
8253   gold_assert(erratum_type == ST_E_843419 || erratum_type == ST_E_835769);
8254   The_stub_table* stub_table = relobj->stub_table(shndx);
8255   gold_assert(stub_table != NULL);
8256   if (stub_table->find_erratum_stub(relobj,
8257                                     shndx,
8258                                     erratum_insn_offset) == NULL)
8259     {
8260       const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
8261       The_erratum_stub* stub;
8262       if (erratum_type == ST_E_835769)
8263         stub = new The_erratum_stub(relobj, erratum_type, shndx,
8264                                     erratum_insn_offset);
8265       else if (erratum_type == ST_E_843419)
8266         stub = new E843419_stub<size, big_endian>(
8267             relobj, shndx, erratum_insn_offset, e843419_adrp_offset);
8268       else
8269         gold_unreachable();
8270       stub->set_erratum_insn(erratum_insn);
8271       stub->set_erratum_address(erratum_address);
8272       // For erratum ST_E_843419 and ST_E_835769, the destination address is
8273       // always the next insn after erratum insn.
8274       stub->set_destination_address(erratum_address + BPI);
8275       stub_table->add_erratum_stub(stub);
8276     }
8277 }
8278
8279
8280 // Scan erratum for section SHNDX range [output_address + span_start,
8281 // output_address + span_end). Note here we do not share the code with
8282 // scan_erratum_843419_span function, because for 843419 we optimize by only
8283 // scanning the last few insns of a page, whereas for 835769, we need to scan
8284 // every insn.
8285
8286 template<int size, bool big_endian>
8287 void
8288 Target_aarch64<size, big_endian>::scan_erratum_835769_span(
8289     AArch64_relobj<size, big_endian>*  relobj,
8290     unsigned int shndx,
8291     const section_size_type span_start,
8292     const section_size_type span_end,
8293     unsigned char* input_view,
8294     Address output_address)
8295 {
8296   typedef typename Insn_utilities::Insntype Insntype;
8297
8298   const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
8299
8300   // Adjust output_address and view to the start of span.
8301   output_address += span_start;
8302   input_view += span_start;
8303
8304   section_size_type span_length = span_end - span_start;
8305   section_size_type offset = 0;
8306   for (offset = 0; offset + BPI < span_length; offset += BPI)
8307     {
8308       Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
8309       Insntype insn1 = ip[0];
8310       Insntype insn2 = ip[1];
8311       if (is_erratum_835769_sequence(insn1, insn2))
8312         {
8313           Insntype erratum_insn = insn2;
8314           // "span_start + offset" is the offset for insn1. So for insn2, it is
8315           // "span_start + offset + BPI".
8316           section_size_type erratum_insn_offset = span_start + offset + BPI;
8317           Address erratum_address = output_address + offset + BPI;
8318           gold_info(_("Erratum 835769 found and fixed at \"%s\", "
8319                          "section %d, offset 0x%08x."),
8320                        relobj->name().c_str(), shndx,
8321                        (unsigned int)(span_start + offset));
8322
8323           this->create_erratum_stub(relobj, shndx,
8324                                     erratum_insn_offset, erratum_address,
8325                                     erratum_insn, ST_E_835769);
8326           offset += BPI;  // Skip mac insn.
8327         }
8328     }
8329 }  // End of "Target_aarch64::scan_erratum_835769_span".
8330
8331
8332 // Scan erratum for section SHNDX range
8333 // [output_address + span_start, output_address + span_end).
8334
8335 template<int size, bool big_endian>
8336 void
8337 Target_aarch64<size, big_endian>::scan_erratum_843419_span(
8338     AArch64_relobj<size, big_endian>*  relobj,
8339     unsigned int shndx,
8340     const section_size_type span_start,
8341     const section_size_type span_end,
8342     unsigned char* input_view,
8343     Address output_address)
8344 {
8345   typedef typename Insn_utilities::Insntype Insntype;
8346
8347   // Adjust output_address and view to the start of span.
8348   output_address += span_start;
8349   input_view += span_start;
8350
8351   if ((output_address & 0x03) != 0)
8352     return;
8353
8354   section_size_type offset = 0;
8355   section_size_type span_length = span_end - span_start;
8356   // The first instruction must be ending at 0xFF8 or 0xFFC.
8357   unsigned int page_offset = output_address & 0xFFF;
8358   // Make sure starting position, that is "output_address+offset",
8359   // starts at page position 0xff8 or 0xffc.
8360   if (page_offset < 0xff8)
8361     offset = 0xff8 - page_offset;
8362   while (offset + 3 * Insn_utilities::BYTES_PER_INSN <= span_length)
8363     {
8364       Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
8365       Insntype insn1 = ip[0];
8366       if (Insn_utilities::is_adrp(insn1))
8367         {
8368           Insntype insn2 = ip[1];
8369           Insntype insn3 = ip[2];
8370           Insntype erratum_insn;
8371           unsigned insn_offset;
8372           bool do_report = false;
8373           if (is_erratum_843419_sequence(insn1, insn2, insn3))
8374             {
8375               do_report = true;
8376               erratum_insn = insn3;
8377               insn_offset = 2 * Insn_utilities::BYTES_PER_INSN;
8378             }
8379           else if (offset + 4 * Insn_utilities::BYTES_PER_INSN <= span_length)
8380             {
8381               // Optionally we can have an insn between ins2 and ins3
8382               Insntype insn_opt = ip[2];
8383               // And insn_opt must not be a branch.
8384               if (!Insn_utilities::aarch64_b(insn_opt)
8385                   && !Insn_utilities::aarch64_bl(insn_opt)
8386                   && !Insn_utilities::aarch64_blr(insn_opt)
8387                   && !Insn_utilities::aarch64_br(insn_opt))
8388                 {
8389                   // And insn_opt must not write to dest reg in insn1. However
8390                   // we do a conservative scan, which means we may fix/report
8391                   // more than necessary, but it doesn't hurt.
8392
8393                   Insntype insn4 = ip[3];
8394                   if (is_erratum_843419_sequence(insn1, insn2, insn4))
8395                     {
8396                       do_report = true;
8397                       erratum_insn = insn4;
8398                       insn_offset = 3 * Insn_utilities::BYTES_PER_INSN;
8399                     }
8400                 }
8401             }
8402           if (do_report)
8403             {
8404               unsigned int erratum_insn_offset =
8405                 span_start + offset + insn_offset;
8406               Address erratum_address =
8407                 output_address + offset + insn_offset;
8408               create_erratum_stub(relobj, shndx,
8409                                   erratum_insn_offset, erratum_address,
8410                                   erratum_insn, ST_E_843419,
8411                                   span_start + offset);
8412             }
8413         }
8414
8415       // Advance to next candidate instruction. We only consider instruction
8416       // sequences starting at a page offset of 0xff8 or 0xffc.
8417       page_offset = (output_address + offset) & 0xfff;
8418       if (page_offset == 0xff8)
8419         offset += 4;
8420       else  // (page_offset == 0xffc), we move to next page's 0xff8.
8421         offset += 0xffc;
8422     }
8423 }  // End of "Target_aarch64::scan_erratum_843419_span".
8424
8425
8426 // The selector for aarch64 object files.
8427
8428 template<int size, bool big_endian>
8429 class Target_selector_aarch64 : public Target_selector
8430 {
8431  public:
8432   Target_selector_aarch64();
8433
8434   virtual Target*
8435   do_instantiate_target()
8436   { return new Target_aarch64<size, big_endian>(); }
8437 };
8438
8439 template<>
8440 Target_selector_aarch64<32, true>::Target_selector_aarch64()
8441   : Target_selector(elfcpp::EM_AARCH64, 32, true,
8442                     "elf32-bigaarch64", "aarch64_elf32_be_vec")
8443 { }
8444
8445 template<>
8446 Target_selector_aarch64<32, false>::Target_selector_aarch64()
8447   : Target_selector(elfcpp::EM_AARCH64, 32, false,
8448                     "elf32-littleaarch64", "aarch64_elf32_le_vec")
8449 { }
8450
8451 template<>
8452 Target_selector_aarch64<64, true>::Target_selector_aarch64()
8453   : Target_selector(elfcpp::EM_AARCH64, 64, true,
8454                     "elf64-bigaarch64", "aarch64_elf64_be_vec")
8455 { }
8456
8457 template<>
8458 Target_selector_aarch64<64, false>::Target_selector_aarch64()
8459   : Target_selector(elfcpp::EM_AARCH64, 64, false,
8460                     "elf64-littleaarch64", "aarch64_elf64_le_vec")
8461 { }
8462
8463 Target_selector_aarch64<32, true> target_selector_aarch64elf32b;
8464 Target_selector_aarch64<32, false> target_selector_aarch64elf32;
8465 Target_selector_aarch64<64, true> target_selector_aarch64elfb;
8466 Target_selector_aarch64<64, false> target_selector_aarch64elf;
8467
8468 } // End anonymous namespace.