gold/aarch64.cc

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