gold/aarch64.cc

   1 // aarch64.cc -- aarch64 target support for gold.
   2
   3 // Copyright (C) 2014-2017 Free Software Foundation, Inc.
   4 // Written by Jing Yu <jingyu@google.com> and Han Shen <shenhan@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <cstring>
  26 #include <map>
  27 #include <set>
  28
  29 #include "elfcpp.h"
  30 #include "dwarf.h"
  31 #include "parameters.h"
  32 #include "reloc.h"
  33 #include "aarch64.h"
  34 #include "object.h"
  35 #include "symtab.h"
  36 #include "layout.h"
  37 #include "output.h"
  38 #include "copy-relocs.h"
  39 #include "target.h"
  40 #include "target-reloc.h"
  41 #include "target-select.h"
  42 #include "tls.h"
  43 #include "freebsd.h"
  44 #include "nacl.h"
  45 #include "gc.h"
  46 #include "icf.h"
  47 #include "aarch64-reloc-property.h"
  48
  49 // The first three .got.plt entries are reserved.
  50 const int32_t AARCH64_GOTPLT_RESERVE_COUNT = 3;
  51
  52
  53 namespace
  54 {
  55
  56 using namespace gold;
  57
  58 template<int size, bool big_endian>
  59 class Output_data_plt_aarch64;
  60
  61 template<int size, bool big_endian>
  62 class Output_data_plt_aarch64_standard;
  63
  64 template<int size, bool big_endian>
  65 class Target_aarch64;
  66
  67 template<int size, bool big_endian>
  68 class AArch64_relocate_functions;
  69
  70 // Utility class dealing with insns. This is ported from macros in
  71 // bfd/elfnn-aarch64.cc, but wrapped inside a class as static members. This
  72 // class is used in erratum sequence scanning.
  73
  74 template<bool big_endian>
  75 class AArch64_insn_utilities
  76 {
  77 public:
  78   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
  79
  80   static const int BYTES_PER_INSN;
  81
  82   // Zero register encoding - 31.
  83   static const unsigned int AARCH64_ZR;
  84
  85   static unsigned int
  86   aarch64_bit(Insntype insn, int pos)
  87   { return ((1 << pos)  & insn) >> pos; }
  88
  89   static unsigned int
  90   aarch64_bits(Insntype insn, int pos, int l)
  91   { return (insn >> pos) & ((1 << l) - 1); }
  92
  93   // Get the encoding field "op31" of 3-source data processing insns. "op31" is
  94   // the name defined in armv8 insn manual C3.5.9.
  95   static unsigned int
  96   aarch64_op31(Insntype insn)
  97   { return aarch64_bits(insn, 21, 3); }
  98
  99   // Get the encoding field "ra" of 3-source data processing insns. "ra" is the
 100   // third source register. See armv8 insn manual C3.5.9.
 101   static unsigned int
 102   aarch64_ra(Insntype insn)
 103   { return aarch64_bits(insn, 10, 5); }
 104
 105   static bool
 106   is_adr(const Insntype insn)
 107   { return (insn & 0x9F000000) == 0x10000000; }
 108
 109   static bool
 110   is_adrp(const Insntype insn)
 111   { return (insn & 0x9F000000) == 0x90000000; }
 112
 113   static bool
 114   is_mrs_tpidr_el0(const Insntype insn)
 115   { return (insn & 0xFFFFFFE0) == 0xd53bd040; }
 116
 117   static unsigned int
 118   aarch64_rm(const Insntype insn)
 119   { return aarch64_bits(insn, 16, 5); }
 120
 121   static unsigned int
 122   aarch64_rn(const Insntype insn)
 123   { return aarch64_bits(insn, 5, 5); }
 124
 125   static unsigned int
 126   aarch64_rd(const Insntype insn)
 127   { return aarch64_bits(insn, 0, 5); }
 128
 129   static unsigned int
 130   aarch64_rt(const Insntype insn)
 131   { return aarch64_bits(insn, 0, 5); }
 132
 133   static unsigned int
 134   aarch64_rt2(const Insntype insn)
 135   { return aarch64_bits(insn, 10, 5); }
 136
 137   // Encode imm21 into adr. Signed imm21 is in the range of [-1M, 1M).
 138   static Insntype
 139   aarch64_adr_encode_imm(Insntype adr, int imm21)
 140   {
 141     gold_assert(is_adr(adr));
 142     gold_assert(-(1 << 20) <= imm21 && imm21 < (1 << 20));
 143     const int mask19 = (1 << 19) - 1;
 144     const int mask2 = 3;
 145     adr &= ~((mask19 << 5) | (mask2 << 29));
 146     adr |= ((imm21 & mask2) << 29) | (((imm21 >> 2) & mask19) << 5);
 147     return adr;
 148   }
 149
 150   // Retrieve encoded adrp 33-bit signed imm value. This value is obtained by
 151   // 21-bit signed imm encoded in the insn multiplied by 4k (page size) and
 152   // 64-bit sign-extended, resulting in [-4G, 4G) with 12-lsb being 0.
 153   static int64_t
 154   aarch64_adrp_decode_imm(const Insntype adrp)
 155   {
 156     const int mask19 = (1 << 19) - 1;
 157     const int mask2 = 3;
 158     gold_assert(is_adrp(adrp));
 159     // 21-bit imm encoded in adrp.
 160     uint64_t imm = ((adrp >> 29) & mask2) | (((adrp >> 5) & mask19) << 2);
 161     // Retrieve msb of 21-bit-signed imm for sign extension.
 162     uint64_t msbt = (imm >> 20) & 1;
 163     // Real value is imm multiplied by 4k. Value now has 33-bit information.
 164     int64_t value = imm << 12;
 165     // Sign extend to 64-bit by repeating msbt 31 (64-33) times and merge it
 166     // with value.
 167     return ((((uint64_t)(1) << 32) - msbt) << 33) | value;
 168   }
 169
 170   static bool
 171   aarch64_b(const Insntype insn)
 172   { return (insn & 0xFC000000) == 0x14000000; }
 173
 174   static bool
 175   aarch64_bl(const Insntype insn)
 176   { return (insn & 0xFC000000) == 0x94000000; }
 177
 178   static bool
 179   aarch64_blr(const Insntype insn)
 180   { return (insn & 0xFFFFFC1F) == 0xD63F0000; }
 181
 182   static bool
 183   aarch64_br(const Insntype insn)
 184   { return (insn & 0xFFFFFC1F) == 0xD61F0000; }
 185
 186   // All ld/st ops.  See C4-182 of the ARM ARM.  The encoding space for
 187   // LD_PCREL, LDST_RO, LDST_UI and LDST_UIMM cover prefetch ops.
 188   static bool
 189   aarch64_ld(Insntype insn) { return aarch64_bit(insn, 22) == 1; }
 190
 191   static bool
 192   aarch64_ldst(Insntype insn)
 193   { return (insn & 0x0a000000) == 0x08000000; }
 194
 195   static bool
 196   aarch64_ldst_ex(Insntype insn)
 197   { return (insn & 0x3f000000) == 0x08000000; }
 198
 199   static bool
 200   aarch64_ldst_pcrel(Insntype insn)
 201   { return (insn & 0x3b000000) == 0x18000000; }
 202
 203   static bool
 204   aarch64_ldst_nap(Insntype insn)
 205   { return (insn & 0x3b800000) == 0x28000000; }
 206
 207   static bool
 208   aarch64_ldstp_pi(Insntype insn)
 209   { return (insn & 0x3b800000) == 0x28800000; }
 210
 211   static bool
 212   aarch64_ldstp_o(Insntype insn)
 213   { return (insn & 0x3b800000) == 0x29000000; }
 214
 215   static bool
 216   aarch64_ldstp_pre(Insntype insn)
 217   { return (insn & 0x3b800000) == 0x29800000; }
 218
 219   static bool
 220   aarch64_ldst_ui(Insntype insn)
 221   { return (insn & 0x3b200c00) == 0x38000000; }
 222
 223   static bool
 224   aarch64_ldst_piimm(Insntype insn)
 225   { return (insn & 0x3b200c00) == 0x38000400; }
 226
 227   static bool
 228   aarch64_ldst_u(Insntype insn)
 229   { return (insn & 0x3b200c00) == 0x38000800; }
 230
 231   static bool
 232   aarch64_ldst_preimm(Insntype insn)
 233   { return (insn & 0x3b200c00) == 0x38000c00; }
 234
 235   static bool
 236   aarch64_ldst_ro(Insntype insn)
 237   { return (insn & 0x3b200c00) == 0x38200800; }
 238
 239   static bool
 240   aarch64_ldst_uimm(Insntype insn)
 241   { return (insn & 0x3b000000) == 0x39000000; }
 242
 243   static bool
 244   aarch64_ldst_simd_m(Insntype insn)
 245   { return (insn & 0xbfbf0000) == 0x0c000000; }
 246
 247   static bool
 248   aarch64_ldst_simd_m_pi(Insntype insn)
 249   { return (insn & 0xbfa00000) == 0x0c800000; }
 250
 251   static bool
 252   aarch64_ldst_simd_s(Insntype insn)
 253   { return (insn & 0xbf9f0000) == 0x0d000000; }
 254
 255   static bool
 256   aarch64_ldst_simd_s_pi(Insntype insn)
 257   { return (insn & 0xbf800000) == 0x0d800000; }
 258
 259   // Classify an INSN if it is indeed a load/store. Return true if INSN is a
 260   // LD/ST instruction otherwise return false. For scalar LD/ST instructions
 261   // PAIR is FALSE, RT is returned and RT2 is set equal to RT. For LD/ST pair
 262   // instructions PAIR is TRUE, RT and RT2 are returned.
 263   static bool
 264   aarch64_mem_op_p(Insntype insn, unsigned int *rt, unsigned int *rt2,
 265                    bool *pair, bool *load)
 266   {
 267     uint32_t opcode;
 268     unsigned int r;
 269     uint32_t opc = 0;
 270     uint32_t v = 0;
 271     uint32_t opc_v = 0;
 272
 273     /* Bail out quickly if INSN doesn't fall into the load-store
 274        encoding space.  */
 275     if (!aarch64_ldst (insn))
 276       return false;
 277
 278     *pair = false;
 279     *load = false;
 280     if (aarch64_ldst_ex (insn))
 281       {
 282         *rt = aarch64_rt (insn);
 283         *rt2 = *rt;
 284         if (aarch64_bit (insn, 21) == 1)
 285           {
 286             *pair = true;
 287             *rt2 = aarch64_rt2 (insn);
 288           }
 289         *load = aarch64_ld (insn);
 290         return true;
 291       }
 292     else if (aarch64_ldst_nap (insn)
 293              || aarch64_ldstp_pi (insn)
 294              || aarch64_ldstp_o (insn)
 295              || aarch64_ldstp_pre (insn))
 296       {
 297         *pair = true;
 298         *rt = aarch64_rt (insn);
 299         *rt2 = aarch64_rt2 (insn);
 300         *load = aarch64_ld (insn);
 301         return true;
 302       }
 303     else if (aarch64_ldst_pcrel (insn)
 304              || aarch64_ldst_ui (insn)
 305              || aarch64_ldst_piimm (insn)
 306              || aarch64_ldst_u (insn)
 307              || aarch64_ldst_preimm (insn)
 308              || aarch64_ldst_ro (insn)
 309              || aarch64_ldst_uimm (insn))
 310       {
 311         *rt = aarch64_rt (insn);
 312         *rt2 = *rt;
 313         if (aarch64_ldst_pcrel (insn))
 314           *load = true;
 315         opc = aarch64_bits (insn, 22, 2);
 316         v = aarch64_bit (insn, 26);
 317         opc_v = opc | (v << 2);
 318         *load =  (opc_v == 1 || opc_v == 2 || opc_v == 3
 319                   || opc_v == 5 || opc_v == 7);
 320         return true;
 321       }
 322     else if (aarch64_ldst_simd_m (insn)
 323              || aarch64_ldst_simd_m_pi (insn))
 324       {
 325         *rt = aarch64_rt (insn);
 326         *load = aarch64_bit (insn, 22);
 327         opcode = (insn >> 12) & 0xf;
 328         switch (opcode)
 329           {
 330           case 0:
 331           case 2:
 332             *rt2 = *rt + 3;
 333             break;
 334
 335           case 4:
 336           case 6:
 337             *rt2 = *rt + 2;
 338             break;
 339
 340           case 7:
 341             *rt2 = *rt;
 342             break;
 343
 344           case 8:
 345           case 10:
 346             *rt2 = *rt + 1;
 347             break;
 348
 349           default:
 350             return false;
 351           }
 352         return true;
 353       }
 354     else if (aarch64_ldst_simd_s (insn)
 355              || aarch64_ldst_simd_s_pi (insn))
 356       {
 357         *rt = aarch64_rt (insn);
 358         r = (insn >> 21) & 1;
 359         *load = aarch64_bit (insn, 22);
 360         opcode = (insn >> 13) & 0x7;
 361         switch (opcode)
 362           {
 363           case 0:
 364           case 2:
 365           case 4:
 366             *rt2 = *rt + r;
 367             break;
 368
 369           case 1:
 370           case 3:
 371           case 5:
 372             *rt2 = *rt + (r == 0 ? 2 : 3);
 373             break;
 374
 375           case 6:
 376             *rt2 = *rt + r;
 377             break;
 378
 379           case 7:
 380             *rt2 = *rt + (r == 0 ? 2 : 3);
 381             break;
 382
 383           default:
 384             return false;
 385           }
 386         return true;
 387       }
 388     return false;
 389   }  // End of "aarch64_mem_op_p".
 390
 391   // Return true if INSN is mac insn.
 392   static bool
 393   aarch64_mac(Insntype insn)
 394   { return (insn & 0xff000000) == 0x9b000000; }
 395
 396   // Return true if INSN is multiply-accumulate.
 397   // (This is similar to implementaton in elfnn-aarch64.c.)
 398   static bool
 399   aarch64_mlxl(Insntype insn)
 400   {
 401     uint32_t op31 = aarch64_op31(insn);
 402     if (aarch64_mac(insn)
 403         && (op31 == 0 || op31 == 1 || op31 == 5)
 404         /* Exclude MUL instructions which are encoded as a multiple-accumulate
 405            with RA = XZR.  */
 406         && aarch64_ra(insn) != AARCH64_ZR)
 407       {
 408         return true;
 409       }
 410     return false;
 411   }
 412 };  // End of "AArch64_insn_utilities".
 413
 414
 415 // Insn length in byte.
 416
 417 template<bool big_endian>
 418 const int AArch64_insn_utilities<big_endian>::BYTES_PER_INSN = 4;
 419
 420
 421 // Zero register encoding - 31.
 422
 423 template<bool big_endian>
 424 const unsigned int AArch64_insn_utilities<big_endian>::AARCH64_ZR = 0x1f;
 425
 426
 427 // Output_data_got_aarch64 class.
 428
 429 template<int size, bool big_endian>
 430 class Output_data_got_aarch64 : public Output_data_got<size, big_endian>
 431 {
 432  public:
 433   typedef typename elfcpp::Elf_types<size>::Elf_Addr Valtype;
 434   Output_data_got_aarch64(Symbol_table* symtab, Layout* layout)
 435     : Output_data_got<size, big_endian>(),
 436       symbol_table_(symtab), layout_(layout)
 437   { }
 438
 439   // Add a static entry for the GOT entry at OFFSET.  GSYM is a global
 440   // symbol and R_TYPE is the code of a dynamic relocation that needs to be
 441   // applied in a static link.
 442   void
 443   add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
 444   { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
 445
 446
 447   // Add a static reloc for the GOT entry at OFFSET.  RELOBJ is an object
 448   // defining a local symbol with INDEX.  R_TYPE is the code of a dynamic
 449   // relocation that needs to be applied in a static link.
 450   void
 451   add_static_reloc(unsigned int got_offset, unsigned int r_type,
 452                    Sized_relobj_file<size, big_endian>* relobj,
 453                    unsigned int index)
 454   {
 455     this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
 456                                                 index));
 457   }
 458
 459
 460  protected:
 461   // Write out the GOT table.
 462   void
 463   do_write(Output_file* of) {
 464     // The first entry in the GOT is the address of the .dynamic section.
 465     gold_assert(this->data_size() >= size / 8);
 466     Output_section* dynamic = this->layout_->dynamic_section();
 467     Valtype dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
 468     this->replace_constant(0, dynamic_addr);
 469     Output_data_got<size, big_endian>::do_write(of);
 470
 471     // Handling static relocs
 472     if (this->static_relocs_.empty())
 473       return;
 474
 475     typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
 476
 477     gold_assert(parameters->doing_static_link());
 478     const off_t offset = this->offset();
 479     const section_size_type oview_size =
 480       convert_to_section_size_type(this->data_size());
 481     unsigned char* const oview = of->get_output_view(offset, oview_size);
 482
 483     Output_segment* tls_segment = this->layout_->tls_segment();
 484     gold_assert(tls_segment != NULL);
 485
 486     AArch64_address aligned_tcb_address =
 487       align_address(Target_aarch64<size, big_endian>::TCB_SIZE,
 488                     tls_segment->maximum_alignment());
 489
 490     for (size_t i = 0; i < this->static_relocs_.size(); ++i)
 491       {
 492         Static_reloc& reloc(this->static_relocs_[i]);
 493         AArch64_address value;
 494
 495         if (!reloc.symbol_is_global())
 496           {
 497             Sized_relobj_file<size, big_endian>* object = reloc.relobj();
 498             const Symbol_value<size>* psymval =
 499               reloc.relobj()->local_symbol(reloc.index());
 500
 501             // We are doing static linking.  Issue an error and skip this
 502             // relocation if the symbol is undefined or in a discarded_section.
 503             bool is_ordinary;
 504             unsigned int shndx = psymval->input_shndx(&is_ordinary);
 505             if ((shndx == elfcpp::SHN_UNDEF)
 506                 || (is_ordinary
 507                     && shndx != elfcpp::SHN_UNDEF
 508                     && !object->is_section_included(shndx)
 509                     && !this->symbol_table_->is_section_folded(object, shndx)))
 510               {
 511                 gold_error(_("undefined or discarded local symbol %u from "
 512                              " object %s in GOT"),
 513                            reloc.index(), reloc.relobj()->name().c_str());
 514                 continue;
 515               }
 516             value = psymval->value(object, 0);
 517           }
 518         else
 519           {
 520             const Symbol* gsym = reloc.symbol();
 521             gold_assert(gsym != NULL);
 522             if (gsym->is_forwarder())
 523               gsym = this->symbol_table_->resolve_forwards(gsym);
 524
 525             // We are doing static linking.  Issue an error and skip this
 526             // relocation if the symbol is undefined or in a discarded_section
 527             // unless it is a weakly_undefined symbol.
 528             if ((gsym->is_defined_in_discarded_section()
 529                  || gsym->is_undefined())
 530                 && !gsym->is_weak_undefined())
 531               {
 532                 gold_error(_("undefined or discarded symbol %s in GOT"),
 533                            gsym->name());
 534                 continue;
 535               }
 536
 537             if (!gsym->is_weak_undefined())
 538               {
 539                 const Sized_symbol<size>* sym =
 540                   static_cast<const Sized_symbol<size>*>(gsym);
 541                 value = sym->value();
 542               }
 543             else
 544               value = 0;
 545           }
 546
 547         unsigned got_offset = reloc.got_offset();
 548         gold_assert(got_offset < oview_size);
 549
 550         typedef typename elfcpp::Swap<size, big_endian>::Valtype Valtype;
 551         Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
 552         Valtype x;
 553         switch (reloc.r_type())
 554           {
 555           case elfcpp::R_AARCH64_TLS_DTPREL64:
 556             x = value;
 557             break;
 558           case elfcpp::R_AARCH64_TLS_TPREL64:
 559             x = value + aligned_tcb_address;
 560             break;
 561           default:
 562             gold_unreachable();
 563           }
 564         elfcpp::Swap<size, big_endian>::writeval(wv, x);
 565       }
 566
 567     of->write_output_view(offset, oview_size, oview);
 568   }
 569
 570  private:
 571   // Symbol table of the output object.
 572   Symbol_table* symbol_table_;
 573   // A pointer to the Layout class, so that we can find the .dynamic
 574   // section when we write out the GOT section.
 575   Layout* layout_;
 576
 577   // This class represent dynamic relocations that need to be applied by
 578   // gold because we are using TLS relocations in a static link.
 579   class Static_reloc
 580   {
 581    public:
 582     Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
 583       : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
 584     { this->u_.global.symbol = gsym; }
 585
 586     Static_reloc(unsigned int got_offset, unsigned int r_type,
 587           Sized_relobj_file<size, big_endian>* relobj, unsigned int index)
 588       : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
 589     {
 590       this->u_.local.relobj = relobj;
 591       this->u_.local.index = index;
 592     }
 593
 594     // Return the GOT offset.
 595     unsigned int
 596     got_offset() const
 597     { return this->got_offset_; }
 598
 599     // Relocation type.
 600     unsigned int
 601     r_type() const
 602     { return this->r_type_; }
 603
 604     // Whether the symbol is global or not.
 605     bool
 606     symbol_is_global() const
 607     { return this->symbol_is_global_; }
 608
 609     // For a relocation against a global symbol, the global symbol.
 610     Symbol*
 611     symbol() const
 612     {
 613       gold_assert(this->symbol_is_global_);
 614       return this->u_.global.symbol;
 615     }
 616
 617     // For a relocation against a local symbol, the defining object.
 618     Sized_relobj_file<size, big_endian>*
 619     relobj() const
 620     {
 621       gold_assert(!this->symbol_is_global_);
 622       return this->u_.local.relobj;
 623     }
 624
 625     // For a relocation against a local symbol, the local symbol index.
 626     unsigned int
 627     index() const
 628     {
 629       gold_assert(!this->symbol_is_global_);
 630       return this->u_.local.index;
 631     }
 632
 633    private:
 634     // GOT offset of the entry to which this relocation is applied.
 635     unsigned int got_offset_;
 636     // Type of relocation.
 637     unsigned int r_type_;
 638     // Whether this relocation is against a global symbol.
 639     bool symbol_is_global_;
 640     // A global or local symbol.
 641     union
 642     {
 643       struct
 644       {
 645         // For a global symbol, the symbol itself.
 646         Symbol* symbol;
 647       } global;
 648       struct
 649       {
 650         // For a local symbol, the object defining the symbol.
 651         Sized_relobj_file<size, big_endian>* relobj;
 652         // For a local symbol, the symbol index.
 653         unsigned int index;
 654       } local;
 655     } u_;
 656   };  // End of inner class Static_reloc
 657
 658   std::vector<Static_reloc> static_relocs_;
 659 };  // End of Output_data_got_aarch64
 660
 661
 662 template<int size, bool big_endian>
 663 class AArch64_input_section;
 664
 665
 666 template<int size, bool big_endian>
 667 class AArch64_output_section;
 668
 669
 670 template<int size, bool big_endian>
 671 class AArch64_relobj;
 672
 673
 674 // Stub type enum constants.
 675
 676 enum
 677 {
 678   ST_NONE = 0,
 679
 680   // Using adrp/add pair, 4 insns (including alignment) without mem access,
 681   // the fastest stub. This has a limited jump distance, which is tested by
 682   // aarch64_valid_for_adrp_p.
 683   ST_ADRP_BRANCH = 1,
 684
 685   // Using ldr-absolute-address/br-register, 4 insns with 1 mem access,
 686   // unlimited in jump distance.
 687   ST_LONG_BRANCH_ABS = 2,
 688
 689   // Using ldr/calculate-pcrel/jump, 8 insns (including alignment) with 1
 690   // mem access, slowest one. Only used in position independent executables.
 691   ST_LONG_BRANCH_PCREL = 3,
 692
 693   // Stub for erratum 843419 handling.
 694   ST_E_843419 = 4,
 695
 696   // Stub for erratum 835769 handling.
 697   ST_E_835769 = 5,
 698
 699   // Number of total stub types.
 700   ST_NUMBER = 6
 701 };
 702
 703
 704 // Struct that wraps insns for a particular stub. All stub templates are
 705 // created/initialized as constants by Stub_template_repertoire.
 706
 707 template<bool big_endian>
 708 struct Stub_template
 709 {
 710   const typename AArch64_insn_utilities<big_endian>::Insntype* insns;
 711   const int insn_num;
 712 };
 713
 714
 715 // Simple singleton class that creates/initializes/stores all types of stub
 716 // templates.
 717
 718 template<bool big_endian>
 719 class Stub_template_repertoire
 720 {
 721 public:
 722   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
 723
 724   // Single static method to get stub template for a given stub type.
 725   static const Stub_template<big_endian>*
 726   get_stub_template(int type)
 727   {
 728     static Stub_template_repertoire<big_endian> singleton;
 729     return singleton.stub_templates_[type];
 730   }
 731
 732 private:
 733   // Constructor - creates/initializes all stub templates.
 734   Stub_template_repertoire();
 735   ~Stub_template_repertoire()
 736   { }
 737
 738   // Disallowing copy ctor and copy assignment operator.
 739   Stub_template_repertoire(Stub_template_repertoire&);
 740   Stub_template_repertoire& operator=(Stub_template_repertoire&);
 741
 742   // Data that stores all insn templates.
 743   const Stub_template<big_endian>* stub_templates_[ST_NUMBER];
 744 };  // End of "class Stub_template_repertoire".
 745
 746
 747 // Constructor - creates/initilizes all stub templates.
 748
 749 template<bool big_endian>
 750 Stub_template_repertoire<big_endian>::Stub_template_repertoire()
 751 {
 752   // Insn array definitions.
 753   const static Insntype ST_NONE_INSNS[] = {};
 754
 755   const static Insntype ST_ADRP_BRANCH_INSNS[] =
 756     {
 757       0x90000010,       /*      adrp    ip0, X             */
 758                         /*        ADR_PREL_PG_HI21(X)      */
 759       0x91000210,       /*      add     ip0, ip0, :lo12:X  */
 760                         /*        ADD_ABS_LO12_NC(X)       */
 761       0xd61f0200,       /*      br      ip0                */
 762       0x00000000,       /*      alignment padding          */
 763     };
 764
 765   const static Insntype ST_LONG_BRANCH_ABS_INSNS[] =
 766     {
 767       0x58000050,       /*      ldr   ip0, 0x8             */
 768       0xd61f0200,       /*      br    ip0                  */
 769       0x00000000,       /*      address field              */
 770       0x00000000,       /*      address fields             */
 771     };
 772
 773   const static Insntype ST_LONG_BRANCH_PCREL_INSNS[] =
 774     {
 775       0x58000090,       /*      ldr   ip0, 0x10            */
 776       0x10000011,       /*      adr   ip1, #0              */
 777       0x8b110210,       /*      add   ip0, ip0, ip1        */
 778       0xd61f0200,       /*      br    ip0                  */
 779       0x00000000,       /*      address field              */
 780       0x00000000,       /*      address field              */
 781       0x00000000,       /*      alignment padding          */
 782       0x00000000,       /*      alignment padding          */
 783     };
 784
 785   const static Insntype ST_E_843419_INSNS[] =
 786     {
 787       0x00000000,    /* Placeholder for erratum insn. */
 788       0x14000000,    /* b <label> */
 789     };
 790
 791   // ST_E_835769 has the same stub template as ST_E_843419
 792   // but we reproduce the array here so that the sizeof
 793   // expressions in install_insn_template will work.
 794   const static Insntype ST_E_835769_INSNS[] =
 795     {
 796       0x00000000,    /* Placeholder for erratum insn. */
 797       0x14000000,    /* b <label> */
 798     };
 799
 800 #define install_insn_template(T) \
 801   const static Stub_template<big_endian> template_##T = {  \
 802     T##_INSNS, sizeof(T##_INSNS) / sizeof(T##_INSNS[0]) }; \
 803   this->stub_templates_[T] = &template_##T
 804
 805   install_insn_template(ST_NONE);
 806   install_insn_template(ST_ADRP_BRANCH);
 807   install_insn_template(ST_LONG_BRANCH_ABS);
 808   install_insn_template(ST_LONG_BRANCH_PCREL);
 809   install_insn_template(ST_E_843419);
 810   install_insn_template(ST_E_835769);
 811
 812 #undef install_insn_template
 813 }
 814
 815
 816 // Base class for stubs.
 817
 818 template<int size, bool big_endian>
 819 class Stub_base
 820 {
 821 public:
 822   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
 823   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
 824
 825   static const AArch64_address invalid_address =
 826     static_cast<AArch64_address>(-1);
 827
 828   static const section_offset_type invalid_offset =
 829     static_cast<section_offset_type>(-1);
 830
 831   Stub_base(int type)
 832     : destination_address_(invalid_address),
 833       offset_(invalid_offset),
 834       type_(type)
 835   {}
 836
 837   ~Stub_base()
 838   {}
 839
 840   // Get stub type.
 841   int
 842   type() const
 843   { return this->type_; }
 844
 845   // Get stub template that provides stub insn information.
 846   const Stub_template<big_endian>*
 847   stub_template() const
 848   {
 849     return Stub_template_repertoire<big_endian>::
 850       get_stub_template(this->type());
 851   }
 852
 853   // Get destination address.
 854   AArch64_address
 855   destination_address() const
 856   {
 857     gold_assert(this->destination_address_ != this->invalid_address);
 858     return this->destination_address_;
 859   }
 860
 861   // Set destination address.
 862   void
 863   set_destination_address(AArch64_address address)
 864   {
 865     gold_assert(address != this->invalid_address);
 866     this->destination_address_ = address;
 867   }
 868
 869   // Reset the destination address.
 870   void
 871   reset_destination_address()
 872   { this->destination_address_ = this->invalid_address; }
 873
 874   // Get offset of code stub. For Reloc_stub, it is the offset from the
 875   // beginning of its containing stub table; for Erratum_stub, it is the offset
 876   // from the end of reloc_stubs.
 877   section_offset_type
 878   offset() const
 879   {
 880     gold_assert(this->offset_ != this->invalid_offset);
 881     return this->offset_;
 882   }
 883
 884   // Set stub offset.
 885   void
 886   set_offset(section_offset_type offset)
 887   { this->offset_ = offset; }
 888
 889   // Return the stub insn.
 890   const Insntype*
 891   insns() const
 892   { return this->stub_template()->insns; }
 893
 894   // Return num of stub insns.
 895   unsigned int
 896   insn_num() const
 897   { return this->stub_template()->insn_num; }
 898
 899   // Get size of the stub.
 900   int
 901   stub_size() const
 902   {
 903     return this->insn_num() *
 904       AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
 905   }
 906
 907   // Write stub to output file.
 908   void
 909   write(unsigned char* view, section_size_type view_size)
 910   { this->do_write(view, view_size); }
 911
 912 protected:
 913   // Abstract method to be implemented by sub-classes.
 914   virtual void
 915   do_write(unsigned char*, section_size_type) = 0;
 916
 917 private:
 918   // The last insn of a stub is a jump to destination insn. This field records
 919   // the destination address.
 920   AArch64_address destination_address_;
 921   // The stub offset. Note this has difference interpretations between an
 922   // Reloc_stub and an Erratum_stub. For Reloc_stub this is the offset from the
 923   // beginning of the containing stub_table, whereas for Erratum_stub, this is
 924   // the offset from the end of reloc_stubs.
 925   section_offset_type offset_;
 926   // Stub type.
 927   const int type_;
 928 };  // End of "Stub_base".
 929
 930
 931 // Erratum stub class. An erratum stub differs from a reloc stub in that for
 932 // each erratum occurrence, we generate an erratum stub. We never share erratum
 933 // stubs, whereas for reloc stubs, different branch insns share a single reloc
 934 // stub as long as the branch targets are the same. (More to the point, reloc
 935 // stubs can be shared because they're used to reach a specific target, whereas
 936 // erratum stubs branch back to the original control flow.)
 937
 938 template<int size, bool big_endian>
 939 class Erratum_stub : public Stub_base<size, big_endian>
 940 {
 941 public:
 942   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
 943   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
 944   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
 945   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
 946
 947   static const int STUB_ADDR_ALIGN;
 948
 949   static const Insntype invalid_insn = static_cast<Insntype>(-1);
 950
 951   Erratum_stub(The_aarch64_relobj* relobj, int type,
 952                unsigned shndx, unsigned int sh_offset)
 953     : Stub_base<size, big_endian>(type), relobj_(relobj),
 954       shndx_(shndx), sh_offset_(sh_offset),
 955       erratum_insn_(invalid_insn),
 956       erratum_address_(this->invalid_address)
 957   {}
 958
 959   ~Erratum_stub() {}
 960
 961   // Return the object that contains the erratum.
 962   The_aarch64_relobj*
 963   relobj()
 964   { return this->relobj_; }
 965
 966   // Get section index of the erratum.
 967   unsigned int
 968   shndx() const
 969   { return this->shndx_; }
 970
 971   // Get section offset of the erratum.
 972   unsigned int
 973   sh_offset() const
 974   { return this->sh_offset_; }
 975
 976   // Get the erratum insn. This is the insn located at erratum_insn_address.
 977   Insntype
 978   erratum_insn() const
 979   {
 980     gold_assert(this->erratum_insn_ != this->invalid_insn);
 981     return this->erratum_insn_;
 982   }
 983
 984   // Set the insn that the erratum happens to.
 985   void
 986   set_erratum_insn(Insntype insn)
 987   { this->erratum_insn_ = insn; }
 988
 989   // For 843419, the erratum insn is ld/st xt, [xn, #uimm], which may be a
 990   // relocation spot, in this case, the erratum_insn_ recorded at scanning phase
 991   // is no longer the one we want to write out to the stub, update erratum_insn_
 992   // with relocated version. Also note that in this case xn must not be "PC", so
 993   // it is safe to move the erratum insn from the origin place to the stub. For
 994   // 835769, the erratum insn is multiply-accumulate insn, which could not be a
 995   // relocation spot (assertion added though).
 996   void
 997   update_erratum_insn(Insntype insn)
 998   {
 999     gold_assert(this->erratum_insn_ != this->invalid_insn);
1000     switch (this->type())
1001       {
1002       case ST_E_843419:
1003         gold_assert(Insn_utilities::aarch64_ldst_uimm(insn));
1004         gold_assert(Insn_utilities::aarch64_ldst_uimm(this->erratum_insn()));
1005         gold_assert(Insn_utilities::aarch64_rd(insn) ==
1006                     Insn_utilities::aarch64_rd(this->erratum_insn()));
1007         gold_assert(Insn_utilities::aarch64_rn(insn) ==
1008                     Insn_utilities::aarch64_rn(this->erratum_insn()));
1009         // Update plain ld/st insn with relocated insn.
1010         this->erratum_insn_ = insn;
1011         break;
1012       case ST_E_835769:
1013         gold_assert(insn == this->erratum_insn());
1014         break;
1015       default:
1016         gold_unreachable();
1017       }
1018   }
1019
1020
1021   // Return the address where an erratum must be done.
1022   AArch64_address
1023   erratum_address() const
1024   {
1025     gold_assert(this->erratum_address_ != this->invalid_address);
1026     return this->erratum_address_;
1027   }
1028
1029   // Set the address where an erratum must be done.
1030   void
1031   set_erratum_address(AArch64_address addr)
1032   { this->erratum_address_ = addr; }
1033
1034   // Comparator used to group Erratum_stubs in a set by (obj, shndx,
1035   // sh_offset). We do not include 'type' in the calculation, because there is
1036   // at most one stub type at (obj, shndx, sh_offset).
1037   bool
1038   operator<(const Erratum_stub<size, big_endian>& k) const
1039   {
1040     if (this == &k)
1041       return false;
1042     // We group stubs by relobj.
1043     if (this->relobj_ != k.relobj_)
1044       return this->relobj_ < k.relobj_;
1045     // Then by section index.
1046     if (this->shndx_ != k.shndx_)
1047       return this->shndx_ < k.shndx_;
1048     // Lastly by section offset.
1049     return this->sh_offset_ < k.sh_offset_;
1050   }
1051
1052   void
1053   invalidate_erratum_stub()
1054   {
1055      gold_assert(this->relobj_ != NULL);
1056      this->relobj_ = NULL;
1057   }
1058
1059   bool
1060   is_invalidated_erratum_stub()
1061   { return this->relobj_ == NULL; }
1062
1063 protected:
1064   virtual void
1065   do_write(unsigned char*, section_size_type);
1066
1067 private:
1068   // The object that needs to be fixed.
1069   The_aarch64_relobj* relobj_;
1070   // The shndx in the object that needs to be fixed.
1071   const unsigned int shndx_;
1072   // The section offset in the obejct that needs to be fixed.
1073   const unsigned int sh_offset_;
1074   // The insn to be fixed.
1075   Insntype erratum_insn_;
1076   // The address of the above insn.
1077   AArch64_address erratum_address_;
1078 };  // End of "Erratum_stub".
1079
1080
1081 // Erratum sub class to wrap additional info needed by 843419.  In fixing this
1082 // erratum, we may choose to replace 'adrp' with 'adr', in this case, we need
1083 // adrp's code position (two or three insns before erratum insn itself).
1084
1085 template<int size, bool big_endian>
1086 class E843419_stub : public Erratum_stub<size, big_endian>
1087 {
1088 public:
1089   typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
1090
1091   E843419_stub(AArch64_relobj<size, big_endian>* relobj,
1092                       unsigned int shndx, unsigned int sh_offset,
1093                       unsigned int adrp_sh_offset)
1094     : Erratum_stub<size, big_endian>(relobj, ST_E_843419, shndx, sh_offset),
1095       adrp_sh_offset_(adrp_sh_offset)
1096   {}
1097
1098   unsigned int
1099   adrp_sh_offset() const
1100   { return this->adrp_sh_offset_; }
1101
1102 private:
1103   // Section offset of "adrp". (We do not need a "adrp_shndx_" field, because we
1104   // can obtain it from its parent.)
1105   const unsigned int adrp_sh_offset_;
1106 };
1107
1108
1109 template<int size, bool big_endian>
1110 const int Erratum_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
1111
1112 // Comparator used in set definition.
1113 template<int size, bool big_endian>
1114 struct Erratum_stub_less
1115 {
1116   bool
1117   operator()(const Erratum_stub<size, big_endian>* s1,
1118              const Erratum_stub<size, big_endian>* s2) const
1119   { return *s1 < *s2; }
1120 };
1121
1122 // Erratum_stub implementation for writing stub to output file.
1123
1124 template<int size, bool big_endian>
1125 void
1126 Erratum_stub<size, big_endian>::do_write(unsigned char* view, section_size_type)
1127 {
1128   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
1129   const Insntype* insns = this->insns();
1130   uint32_t num_insns = this->insn_num();
1131   Insntype* ip = reinterpret_cast<Insntype*>(view);
1132   // For current implemented erratum 843419 and 835769, the first insn in the
1133   // stub is always a copy of the problematic insn (in 843419, the mem access
1134   // insn, in 835769, the mac insn), followed by a jump-back.
1135   elfcpp::Swap<32, big_endian>::writeval(ip, this->erratum_insn());
1136   for (uint32_t i = 1; i < num_insns; ++i)
1137     elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
1138 }
1139
1140
1141 // Reloc stub class.
1142
1143 template<int size, bool big_endian>
1144 class Reloc_stub : public Stub_base<size, big_endian>
1145 {
1146  public:
1147   typedef Reloc_stub<size, big_endian> This;
1148   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1149
1150   // Branch range. This is used to calculate the section group size, as well as
1151   // determine whether a stub is needed.
1152   static const int MAX_BRANCH_OFFSET = ((1 << 25) - 1) << 2;
1153   static const int MIN_BRANCH_OFFSET = -((1 << 25) << 2);
1154
1155   // Constant used to determine if an offset fits in the adrp instruction
1156   // encoding.
1157   static const int MAX_ADRP_IMM = (1 << 20) - 1;
1158   static const int MIN_ADRP_IMM = -(1 << 20);
1159
1160   static const int BYTES_PER_INSN = 4;
1161   static const int STUB_ADDR_ALIGN;
1162
1163   // Determine whether the offset fits in the jump/branch instruction.
1164   static bool
1165   aarch64_valid_branch_offset_p(int64_t offset)
1166   { return offset >= MIN_BRANCH_OFFSET && offset <= MAX_BRANCH_OFFSET; }
1167
1168   // Determine whether the offset fits in the adrp immediate field.
1169   static bool
1170   aarch64_valid_for_adrp_p(AArch64_address location, AArch64_address dest)
1171   {
1172     typedef AArch64_relocate_functions<size, big_endian> Reloc;
1173     int64_t adrp_imm = (Reloc::Page(dest) - Reloc::Page(location)) >> 12;
1174     return adrp_imm >= MIN_ADRP_IMM && adrp_imm <= MAX_ADRP_IMM;
1175   }
1176
1177   // Determine the stub type for a certain relocation or ST_NONE, if no stub is
1178   // needed.
1179   static int
1180   stub_type_for_reloc(unsigned int r_type, AArch64_address address,
1181                       AArch64_address target);
1182
1183   Reloc_stub(int type)
1184     : Stub_base<size, big_endian>(type)
1185   { }
1186
1187   ~Reloc_stub()
1188   { }
1189
1190   // The key class used to index the stub instance in the stub table's stub map.
1191   class Key
1192   {
1193    public:
1194     Key(int type, const Symbol* symbol, const Relobj* relobj,
1195         unsigned int r_sym, int32_t addend)
1196       : type_(type), addend_(addend)
1197     {
1198       if (symbol != NULL)
1199         {
1200           this->r_sym_ = Reloc_stub::invalid_index;
1201           this->u_.symbol = symbol;
1202         }
1203       else
1204         {
1205           gold_assert(relobj != NULL && r_sym != invalid_index);
1206           this->r_sym_ = r_sym;
1207           this->u_.relobj = relobj;
1208         }
1209     }
1210
1211     ~Key()
1212     { }
1213
1214     // Return stub type.
1215     int
1216     type() const
1217     { return this->type_; }
1218
1219     // Return the local symbol index or invalid_index.
1220     unsigned int
1221     r_sym() const
1222     { return this->r_sym_; }
1223
1224     // Return the symbol if there is one.
1225     const Symbol*
1226     symbol() const
1227     { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
1228
1229     // Return the relobj if there is one.
1230     const Relobj*
1231     relobj() const
1232     { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
1233
1234     // Whether this equals to another key k.
1235     bool
1236     eq(const Key& k) const
1237     {
1238       return ((this->type_ == k.type_)
1239               && (this->r_sym_ == k.r_sym_)
1240               && ((this->r_sym_ != Reloc_stub::invalid_index)
1241                   ? (this->u_.relobj == k.u_.relobj)
1242                   : (this->u_.symbol == k.u_.symbol))
1243               && (this->addend_ == k.addend_));
1244     }
1245
1246     // Return a hash value.
1247     size_t
1248     hash_value() const
1249     {
1250       size_t name_hash_value = gold::string_hash<char>(
1251           (this->r_sym_ != Reloc_stub::invalid_index)
1252           ? this->u_.relobj->name().c_str()
1253           : this->u_.symbol->name());
1254       // We only have 4 stub types.
1255       size_t stub_type_hash_value = 0x03 & this->type_;
1256       return (name_hash_value
1257               ^ stub_type_hash_value
1258               ^ ((this->r_sym_ & 0x3fff) << 2)
1259               ^ ((this->addend_ & 0xffff) << 16));
1260     }
1261
1262     // Functors for STL associative containers.
1263     struct hash
1264     {
1265       size_t
1266       operator()(const Key& k) const
1267       { return k.hash_value(); }
1268     };
1269
1270     struct equal_to
1271     {
1272       bool
1273       operator()(const Key& k1, const Key& k2) const
1274       { return k1.eq(k2); }
1275     };
1276
1277    private:
1278     // Stub type.
1279     const int type_;
1280     // If this is a local symbol, this is the index in the defining object.
1281     // Otherwise, it is invalid_index for a global symbol.
1282     unsigned int r_sym_;
1283     // If r_sym_ is an invalid index, this points to a global symbol.
1284     // Otherwise, it points to a relobj.  We used the unsized and target
1285     // independent Symbol and Relobj classes instead of Sized_symbol<32> and
1286     // Arm_relobj, in order to avoid making the stub class a template
1287     // as most of the stub machinery is endianness-neutral.  However, it
1288     // may require a bit of casting done by users of this class.
1289     union
1290     {
1291       const Symbol* symbol;
1292       const Relobj* relobj;
1293     } u_;
1294     // Addend associated with a reloc.
1295     int32_t addend_;
1296   };  // End of inner class Reloc_stub::Key
1297
1298  protected:
1299   // This may be overridden in the child class.
1300   virtual void
1301   do_write(unsigned char*, section_size_type);
1302
1303  private:
1304   static const unsigned int invalid_index = static_cast<unsigned int>(-1);
1305 };  // End of Reloc_stub
1306
1307 template<int size, bool big_endian>
1308 const int Reloc_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
1309
1310 // Write data to output file.
1311
1312 template<int size, bool big_endian>
1313 void
1314 Reloc_stub<size, big_endian>::
1315 do_write(unsigned char* view, section_size_type)
1316 {
1317   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
1318   const uint32_t* insns = this->insns();
1319   uint32_t num_insns = this->insn_num();
1320   Insntype* ip = reinterpret_cast<Insntype*>(view);
1321   for (uint32_t i = 0; i < num_insns; ++i)
1322     elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
1323 }
1324
1325
1326 // Determine the stub type for a certain relocation or ST_NONE, if no stub is
1327 // needed.
1328
1329 template<int size, bool big_endian>
1330 inline int
1331 Reloc_stub<size, big_endian>::stub_type_for_reloc(
1332     unsigned int r_type, AArch64_address location, AArch64_address dest)
1333 {
1334   int64_t branch_offset = 0;
1335   switch(r_type)
1336     {
1337     case elfcpp::R_AARCH64_CALL26:
1338     case elfcpp::R_AARCH64_JUMP26:
1339       branch_offset = dest - location;
1340       break;
1341     default:
1342       gold_unreachable();
1343     }
1344
1345   if (aarch64_valid_branch_offset_p(branch_offset))
1346     return ST_NONE;
1347
1348   if (aarch64_valid_for_adrp_p(location, dest))
1349     return ST_ADRP_BRANCH;
1350
1351   // Always use PC-relative addressing in case of -shared or -pie.
1352   if (parameters->options().output_is_position_independent())
1353     return ST_LONG_BRANCH_PCREL;
1354
1355   // This saves 2 insns per stub, compared to ST_LONG_BRANCH_PCREL.
1356   // But is only applicable to non-shared or non-pie.
1357   return ST_LONG_BRANCH_ABS;
1358 }
1359
1360 // A class to hold stubs for the ARM target. This contains 2 different types of
1361 // stubs - reloc stubs and erratum stubs.
1362
1363 template<int size, bool big_endian>
1364 class Stub_table : public Output_data
1365 {
1366  public:
1367   typedef Target_aarch64<size, big_endian> The_target_aarch64;
1368   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1369   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
1370   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
1371   typedef Reloc_stub<size, big_endian> The_reloc_stub;
1372   typedef typename The_reloc_stub::Key The_reloc_stub_key;
1373   typedef Erratum_stub<size, big_endian> The_erratum_stub;
1374   typedef Erratum_stub_less<size, big_endian> The_erratum_stub_less;
1375   typedef typename The_reloc_stub_key::hash The_reloc_stub_key_hash;
1376   typedef typename The_reloc_stub_key::equal_to The_reloc_stub_key_equal_to;
1377   typedef Stub_table<size, big_endian> The_stub_table;
1378   typedef Unordered_map<The_reloc_stub_key, The_reloc_stub*,
1379                         The_reloc_stub_key_hash, The_reloc_stub_key_equal_to>
1380                         Reloc_stub_map;
1381   typedef typename Reloc_stub_map::const_iterator Reloc_stub_map_const_iter;
1382   typedef Relocate_info<size, big_endian> The_relocate_info;
1383
1384   typedef std::set<The_erratum_stub*, The_erratum_stub_less> Erratum_stub_set;
1385   typedef typename Erratum_stub_set::iterator Erratum_stub_set_iter;
1386
1387   Stub_table(The_aarch64_input_section* owner)
1388     : Output_data(), owner_(owner), reloc_stubs_size_(0),
1389       erratum_stubs_size_(0), prev_data_size_(0)
1390   { }
1391
1392   ~Stub_table()
1393   { }
1394
1395   The_aarch64_input_section*
1396   owner() const
1397   { return owner_; }
1398
1399   // Whether this stub table is empty.
1400   bool
1401   empty() const
1402   { return reloc_stubs_.empty() && erratum_stubs_.empty(); }
1403
1404   // Return the current data size.
1405   off_t
1406   current_data_size() const
1407   { return this->current_data_size_for_child(); }
1408
1409   // Add a STUB using KEY.  The caller is responsible for avoiding addition
1410   // if a STUB with the same key has already been added.
1411   void
1412   add_reloc_stub(The_reloc_stub* stub, const The_reloc_stub_key& key);
1413
1414   // Add an erratum stub into the erratum stub set. The set is ordered by
1415   // (relobj, shndx, sh_offset).
1416   void
1417   add_erratum_stub(The_erratum_stub* stub);
1418
1419   // Find if such erratum exists for any given (obj, shndx, sh_offset).
1420   The_erratum_stub*
1421   find_erratum_stub(The_aarch64_relobj* a64relobj,
1422                     unsigned int shndx, unsigned int sh_offset);
1423
1424   // Find all the erratums for a given input section. The return value is a pair
1425   // of iterators [begin, end).
1426   std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
1427   find_erratum_stubs_for_input_section(The_aarch64_relobj* a64relobj,
1428                                        unsigned int shndx);
1429
1430   // Compute the erratum stub address.
1431   AArch64_address
1432   erratum_stub_address(The_erratum_stub* stub) const
1433   {
1434     AArch64_address r = align_address(this->address() + this->reloc_stubs_size_,
1435                                       The_erratum_stub::STUB_ADDR_ALIGN);
1436     r += stub->offset();
1437     return r;
1438   }
1439
1440   // Finalize stubs. No-op here, just for completeness.
1441   void
1442   finalize_stubs()
1443   { }
1444
1445   // Look up a relocation stub using KEY. Return NULL if there is none.
1446   The_reloc_stub*
1447   find_reloc_stub(The_reloc_stub_key& key)
1448   {
1449     Reloc_stub_map_const_iter p = this->reloc_stubs_.find(key);
1450     return (p != this->reloc_stubs_.end()) ? p->second : NULL;
1451   }
1452
1453   // Relocate reloc stubs in this stub table. This does not relocate erratum stubs.
1454   void
1455   relocate_reloc_stubs(const The_relocate_info*,
1456                        The_target_aarch64*,
1457                        Output_section*,
1458                        unsigned char*,
1459                        AArch64_address,
1460                        section_size_type);
1461
1462   // Relocate an erratum stub.
1463   void
1464   relocate_erratum_stub(The_erratum_stub*, unsigned char*);
1465
1466   // Update data size at the end of a relaxation pass.  Return true if data size
1467   // is different from that of the previous relaxation pass.
1468   bool
1469   update_data_size_changed_p()
1470   {
1471     // No addralign changed here.
1472     off_t s = align_address(this->reloc_stubs_size_,
1473                             The_erratum_stub::STUB_ADDR_ALIGN)
1474               + this->erratum_stubs_size_;
1475     bool changed = (s != this->prev_data_size_);
1476     this->prev_data_size_ = s;
1477     return changed;
1478   }
1479
1480  protected:
1481   // Write out section contents.
1482   void
1483   do_write(Output_file*);
1484
1485   // Return the required alignment.
1486   uint64_t
1487   do_addralign() const
1488   {
1489     return std::max(The_reloc_stub::STUB_ADDR_ALIGN,
1490                     The_erratum_stub::STUB_ADDR_ALIGN);
1491   }
1492
1493   // Reset address and file offset.
1494   void
1495   do_reset_address_and_file_offset()
1496   { this->set_current_data_size_for_child(this->prev_data_size_); }
1497
1498   // Set final data size.
1499   void
1500   set_final_data_size()
1501   { this->set_data_size(this->current_data_size()); }
1502
1503  private:
1504   // Relocate one reloc stub.
1505   void
1506   relocate_reloc_stub(The_reloc_stub*,
1507                       const The_relocate_info*,
1508                       The_target_aarch64*,
1509                       Output_section*,
1510                       unsigned char*,
1511                       AArch64_address,
1512                       section_size_type);
1513
1514  private:
1515   // Owner of this stub table.
1516   The_aarch64_input_section* owner_;
1517   // The relocation stubs.
1518   Reloc_stub_map reloc_stubs_;
1519   // The erratum stubs.
1520   Erratum_stub_set erratum_stubs_;
1521   // Size of reloc stubs.
1522   off_t reloc_stubs_size_;
1523   // Size of erratum stubs.
1524   off_t erratum_stubs_size_;
1525   // data size of this in the previous pass.
1526   off_t prev_data_size_;
1527 };  // End of Stub_table
1528
1529
1530 // Add an erratum stub into the erratum stub set. The set is ordered by
1531 // (relobj, shndx, sh_offset).
1532
1533 template<int size, bool big_endian>
1534 void
1535 Stub_table<size, big_endian>::add_erratum_stub(The_erratum_stub* stub)
1536 {
1537   std::pair<Erratum_stub_set_iter, bool> ret =
1538     this->erratum_stubs_.insert(stub);
1539   gold_assert(ret.second);
1540   this->erratum_stubs_size_ = align_address(
1541         this->erratum_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
1542   stub->set_offset(this->erratum_stubs_size_);
1543   this->erratum_stubs_size_ += stub->stub_size();
1544 }
1545
1546
1547 // Find if such erratum exists for given (obj, shndx, sh_offset).
1548
1549 template<int size, bool big_endian>
1550 Erratum_stub<size, big_endian>*
1551 Stub_table<size, big_endian>::find_erratum_stub(
1552     The_aarch64_relobj* a64relobj, unsigned int shndx, unsigned int sh_offset)
1553 {
1554   // A dummy object used as key to search in the set.
1555   The_erratum_stub key(a64relobj, ST_NONE,
1556                          shndx, sh_offset);
1557   Erratum_stub_set_iter i = this->erratum_stubs_.find(&key);
1558   if (i != this->erratum_stubs_.end())
1559     {
1560         The_erratum_stub* stub(*i);
1561         gold_assert(stub->erratum_insn() != 0);
1562         return stub;
1563     }
1564   return NULL;
1565 }
1566
1567
1568 // Find all the errata for a given input section. The return value is a pair of
1569 // iterators [begin, end).
1570
1571 template<int size, bool big_endian>
1572 std::pair<typename Stub_table<size, big_endian>::Erratum_stub_set_iter,
1573           typename Stub_table<size, big_endian>::Erratum_stub_set_iter>
1574 Stub_table<size, big_endian>::find_erratum_stubs_for_input_section(
1575     The_aarch64_relobj* a64relobj, unsigned int shndx)
1576 {
1577   typedef std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter> Result_pair;
1578   Erratum_stub_set_iter start, end;
1579   The_erratum_stub low_key(a64relobj, ST_NONE, shndx, 0);
1580   start = this->erratum_stubs_.lower_bound(&low_key);
1581   if (start == this->erratum_stubs_.end())
1582     return Result_pair(this->erratum_stubs_.end(),
1583                        this->erratum_stubs_.end());
1584   end = start;
1585   while (end != this->erratum_stubs_.end() &&
1586          (*end)->relobj() == a64relobj && (*end)->shndx() == shndx)
1587     ++end;
1588   return Result_pair(start, end);
1589 }
1590
1591
1592 // Add a STUB using KEY.  The caller is responsible for avoiding addition
1593 // if a STUB with the same key has already been added.
1594
1595 template<int size, bool big_endian>
1596 void
1597 Stub_table<size, big_endian>::add_reloc_stub(
1598     The_reloc_stub* stub, const The_reloc_stub_key& key)
1599 {
1600   gold_assert(stub->type() == key.type());
1601   this->reloc_stubs_[key] = stub;
1602
1603   // Assign stub offset early.  We can do this because we never remove
1604   // reloc stubs and they are in the beginning of the stub table.
1605   this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_,
1606                                           The_reloc_stub::STUB_ADDR_ALIGN);
1607   stub->set_offset(this->reloc_stubs_size_);
1608   this->reloc_stubs_size_ += stub->stub_size();
1609 }
1610
1611
1612 // Relocate an erratum stub.
1613
1614 template<int size, bool big_endian>
1615 void
1616 Stub_table<size, big_endian>::
1617 relocate_erratum_stub(The_erratum_stub* estub,
1618                       unsigned char* view)
1619 {
1620   // Just for convenience.
1621   const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
1622
1623   gold_assert(!estub->is_invalidated_erratum_stub());
1624   AArch64_address stub_address = this->erratum_stub_address(estub);
1625   // The address of "b" in the stub that is to be "relocated".
1626   AArch64_address stub_b_insn_address;
1627   // Branch offset that is to be filled in "b" insn.
1628   int b_offset = 0;
1629   switch (estub->type())
1630     {
1631     case ST_E_843419:
1632     case ST_E_835769:
1633       // The 1st insn of the erratum could be a relocation spot,
1634       // in this case we need to fix it with
1635       // "(*i)->erratum_insn()".
1636       elfcpp::Swap<32, big_endian>::writeval(
1637           view + (stub_address - this->address()),
1638           estub->erratum_insn());
1639       // For the erratum, the 2nd insn is a b-insn to be patched
1640       // (relocated).
1641       stub_b_insn_address = stub_address + 1 * BPI;
1642       b_offset = estub->destination_address() - stub_b_insn_address;
1643       AArch64_relocate_functions<size, big_endian>::construct_b(
1644           view + (stub_b_insn_address - this->address()),
1645           ((unsigned int)(b_offset)) & 0xfffffff);
1646       break;
1647     default:
1648       gold_unreachable();
1649       break;
1650     }
1651   estub->invalidate_erratum_stub();
1652 }
1653
1654
1655 // Relocate only reloc stubs in this stub table. This does not relocate erratum
1656 // stubs.
1657
1658 template<int size, bool big_endian>
1659 void
1660 Stub_table<size, big_endian>::
1661 relocate_reloc_stubs(const The_relocate_info* relinfo,
1662                      The_target_aarch64* target_aarch64,
1663                      Output_section* output_section,
1664                      unsigned char* view,
1665                      AArch64_address address,
1666                      section_size_type view_size)
1667 {
1668   // "view_size" is the total size of the stub_table.
1669   gold_assert(address == this->address() &&
1670               view_size == static_cast<section_size_type>(this->data_size()));
1671   for(Reloc_stub_map_const_iter p = this->reloc_stubs_.begin();
1672       p != this->reloc_stubs_.end(); ++p)
1673     relocate_reloc_stub(p->second, relinfo, target_aarch64, output_section,
1674                         view, address, view_size);
1675 }
1676
1677
1678 // Relocate one reloc stub. This is a helper for
1679 // Stub_table::relocate_reloc_stubs().
1680
1681 template<int size, bool big_endian>
1682 void
1683 Stub_table<size, big_endian>::
1684 relocate_reloc_stub(The_reloc_stub* stub,
1685                     const The_relocate_info* relinfo,
1686                     The_target_aarch64* target_aarch64,
1687                     Output_section* output_section,
1688                     unsigned char* view,
1689                     AArch64_address address,
1690                     section_size_type view_size)
1691 {
1692   // "offset" is the offset from the beginning of the stub_table.
1693   section_size_type offset = stub->offset();
1694   section_size_type stub_size = stub->stub_size();
1695   // "view_size" is the total size of the stub_table.
1696   gold_assert(offset + stub_size <= view_size);
1697
1698   target_aarch64->relocate_reloc_stub(stub, relinfo, output_section,
1699                                       view + offset, address + offset, view_size);
1700 }
1701
1702
1703 // Write out the stubs to file.
1704
1705 template<int size, bool big_endian>
1706 void
1707 Stub_table<size, big_endian>::do_write(Output_file* of)
1708 {
1709   off_t offset = this->offset();
1710   const section_size_type oview_size =
1711     convert_to_section_size_type(this->data_size());
1712   unsigned char* const oview = of->get_output_view(offset, oview_size);
1713
1714   // Write relocation stubs.
1715   for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
1716       p != this->reloc_stubs_.end(); ++p)
1717     {
1718       The_reloc_stub* stub = p->second;
1719       AArch64_address address = this->address() + stub->offset();
1720       gold_assert(address ==
1721                   align_address(address, The_reloc_stub::STUB_ADDR_ALIGN));
1722       stub->write(oview + stub->offset(), stub->stub_size());
1723     }
1724
1725   // Write erratum stubs.
1726   unsigned int erratum_stub_start_offset =
1727     align_address(this->reloc_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
1728   for (typename Erratum_stub_set::iterator p = this->erratum_stubs_.begin();
1729        p != this->erratum_stubs_.end(); ++p)
1730     {
1731       The_erratum_stub* stub(*p);
1732       stub->write(oview + erratum_stub_start_offset + stub->offset(),
1733                   stub->stub_size());
1734     }
1735
1736   of->write_output_view(this->offset(), oview_size, oview);
1737 }
1738
1739
1740 // AArch64_relobj class.
1741
1742 template<int size, bool big_endian>
1743 class AArch64_relobj : public Sized_relobj_file<size, big_endian>
1744 {
1745  public:
1746   typedef AArch64_relobj<size, big_endian> This;
1747   typedef Target_aarch64<size, big_endian> The_target_aarch64;
1748   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
1749   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
1750   typedef Stub_table<size, big_endian> The_stub_table;
1751   typedef Erratum_stub<size, big_endian> The_erratum_stub;
1752   typedef typename The_stub_table::Erratum_stub_set_iter Erratum_stub_set_iter;
1753   typedef std::vector<The_stub_table*> Stub_table_list;
1754   static const AArch64_address invalid_address =
1755       static_cast<AArch64_address>(-1);
1756
1757   AArch64_relobj(const std::string& name, Input_file* input_file, off_t offset,
1758                  const typename elfcpp::Ehdr<size, big_endian>& ehdr)
1759     : Sized_relobj_file<size, big_endian>(name, input_file, offset, ehdr),
1760       stub_tables_()
1761   { }
1762
1763   ~AArch64_relobj()
1764   { }
1765
1766   // Return the stub table of the SHNDX-th section if there is one.
1767   The_stub_table*
1768   stub_table(unsigned int shndx) const
1769   {
1770     gold_assert(shndx < this->stub_tables_.size());
1771     return this->stub_tables_[shndx];
1772   }
1773
1774   // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1775   void
1776   set_stub_table(unsigned int shndx, The_stub_table* stub_table)
1777   {
1778     gold_assert(shndx < this->stub_tables_.size());
1779     this->stub_tables_[shndx] = stub_table;
1780   }
1781
1782   // Entrance to errata scanning.
1783   void
1784   scan_errata(unsigned int shndx,
1785               const elfcpp::Shdr<size, big_endian>&,
1786               Output_section*, const Symbol_table*,
1787               The_target_aarch64*);
1788
1789   // Scan all relocation sections for stub generation.
1790   void
1791   scan_sections_for_stubs(The_target_aarch64*, const Symbol_table*,
1792                           const Layout*);
1793
1794   // Whether a section is a scannable text section.
1795   bool
1796   text_section_is_scannable(const elfcpp::Shdr<size, big_endian>&, unsigned int,
1797                             const Output_section*, const Symbol_table*);
1798
1799   // Convert regular input section with index SHNDX to a relaxed section.
1800   void
1801   convert_input_section_to_relaxed_section(unsigned shndx)
1802   {
1803     // The stubs have relocations and we need to process them after writing
1804     // out the stubs.  So relocation now must follow section write.
1805     this->set_section_offset(shndx, -1ULL);
1806     this->set_relocs_must_follow_section_writes();
1807   }
1808
1809   // Structure for mapping symbol position.
1810   struct Mapping_symbol_position
1811   {
1812     Mapping_symbol_position(unsigned int shndx, AArch64_address offset):
1813       shndx_(shndx), offset_(offset)
1814     {}
1815
1816     // "<" comparator used in ordered_map container.
1817     bool
1818     operator<(const Mapping_symbol_position& p) const
1819     {
1820       return (this->shndx_ < p.shndx_
1821               || (this->shndx_ == p.shndx_ && this->offset_ < p.offset_));
1822     }
1823
1824     // Section index.
1825     unsigned int shndx_;
1826
1827     // Section offset.
1828     AArch64_address offset_;
1829   };
1830
1831   typedef std::map<Mapping_symbol_position, char> Mapping_symbol_info;
1832
1833  protected:
1834   // Post constructor setup.
1835   void
1836   do_setup()
1837   {
1838     // Call parent's setup method.
1839     Sized_relobj_file<size, big_endian>::do_setup();
1840
1841     // Initialize look-up tables.
1842     this->stub_tables_.resize(this->shnum());
1843   }
1844
1845   virtual void
1846   do_relocate_sections(
1847       const Symbol_table* symtab, const Layout* layout,
1848       const unsigned char* pshdrs, Output_file* of,
1849       typename Sized_relobj_file<size, big_endian>::Views* pviews);
1850
1851   // Count local symbols and (optionally) record mapping info.
1852   virtual void
1853   do_count_local_symbols(Stringpool_template<char>*,
1854                          Stringpool_template<char>*);
1855
1856  private:
1857   // Fix all errata in the object, and for each erratum, relocate corresponding
1858   // erratum stub.
1859   void
1860   fix_errata_and_relocate_erratum_stubs(
1861       typename Sized_relobj_file<size, big_endian>::Views* pviews);
1862
1863   // Try to fix erratum 843419 in an optimized way. Return true if patch is
1864   // applied.
1865   bool
1866   try_fix_erratum_843419_optimized(
1867       The_erratum_stub*, AArch64_address,
1868       typename Sized_relobj_file<size, big_endian>::View_size&);
1869
1870   // Whether a section needs to be scanned for relocation stubs.
1871   bool
1872   section_needs_reloc_stub_scanning(const elfcpp::Shdr<size, big_endian>&,
1873                                     const Relobj::Output_sections&,
1874                                     const Symbol_table*, const unsigned char*);
1875
1876   // List of stub tables.
1877   Stub_table_list stub_tables_;
1878
1879   // Mapping symbol information sorted by (section index, section_offset).
1880   Mapping_symbol_info mapping_symbol_info_;
1881 };  // End of AArch64_relobj
1882
1883
1884 // Override to record mapping symbol information.
1885 template<int size, bool big_endian>
1886 void
1887 AArch64_relobj<size, big_endian>::do_count_local_symbols(
1888     Stringpool_template<char>* pool, Stringpool_template<char>* dynpool)
1889 {
1890   Sized_relobj_file<size, big_endian>::do_count_local_symbols(pool, dynpool);
1891
1892   // Only erratum-fixing work needs mapping symbols, so skip this time consuming
1893   // processing if not fixing erratum.
1894   if (!parameters->options().fix_cortex_a53_843419()
1895       && !parameters->options().fix_cortex_a53_835769())
1896     return;
1897
1898   const unsigned int loccount = this->local_symbol_count();
1899   if (loccount == 0)
1900     return;
1901
1902   // Read the symbol table section header.
1903   const unsigned int symtab_shndx = this->symtab_shndx();
1904   elfcpp::Shdr<size, big_endian>
1905       symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
1906   gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
1907
1908   // Read the local symbols.
1909   const int sym_size =elfcpp::Elf_sizes<size>::sym_size;
1910   gold_assert(loccount == symtabshdr.get_sh_info());
1911   off_t locsize = loccount * sym_size;
1912   const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
1913                                               locsize, true, true);
1914
1915   // For mapping symbol processing, we need to read the symbol names.
1916   unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
1917   if (strtab_shndx >= this->shnum())
1918     {
1919       this->error(_("invalid symbol table name index: %u"), strtab_shndx);
1920       return;
1921     }
1922
1923   elfcpp::Shdr<size, big_endian>
1924     strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
1925   if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
1926     {
1927       this->error(_("symbol table name section has wrong type: %u"),
1928                   static_cast<unsigned int>(strtabshdr.get_sh_type()));
1929       return;
1930     }
1931
1932   const char* pnames =
1933     reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
1934                                                  strtabshdr.get_sh_size(),
1935                                                  false, false));
1936
1937   // Skip the first dummy symbol.
1938   psyms += sym_size;
1939   typename Sized_relobj_file<size, big_endian>::Local_values*
1940     plocal_values = this->local_values();
1941   for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
1942     {
1943       elfcpp::Sym<size, big_endian> sym(psyms);
1944       Symbol_value<size>& lv((*plocal_values)[i]);
1945       AArch64_address input_value = lv.input_value();
1946
1947       // Check to see if this is a mapping symbol. AArch64 mapping symbols are
1948       // defined in "ELF for the ARM 64-bit Architecture", Table 4-4, Mapping
1949       // symbols.
1950       // Mapping symbols could be one of the following 4 forms -
1951       //   a) $x
1952       //   b) $x.<any...>
1953       //   c) $d
1954       //   d) $d.<any...>
1955       const char* sym_name = pnames + sym.get_st_name();
1956       if (sym_name[0] == '$' && (sym_name[1] == 'x' || sym_name[1] == 'd')
1957           && (sym_name[2] == '\0' || sym_name[2] == '.'))
1958         {
1959           bool is_ordinary;
1960           unsigned int input_shndx =
1961             this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
1962           gold_assert(is_ordinary);
1963
1964           Mapping_symbol_position msp(input_shndx, input_value);
1965           // Insert mapping_symbol_info into map whose ordering is defined by
1966           // (shndx, offset_within_section).
1967           this->mapping_symbol_info_[msp] = sym_name[1];
1968         }
1969    }
1970 }
1971
1972
1973 // Fix all errata in the object and for each erratum, we relocate the
1974 // corresponding erratum stub (by calling Stub_table::relocate_erratum_stub).
1975
1976 template<int size, bool big_endian>
1977 void
1978 AArch64_relobj<size, big_endian>::fix_errata_and_relocate_erratum_stubs(
1979     typename Sized_relobj_file<size, big_endian>::Views* pviews)
1980 {
1981   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
1982   unsigned int shnum = this->shnum();
1983   const Relobj::Output_sections& out_sections(this->output_sections());
1984   for (unsigned int i = 1; i < shnum; ++i)
1985     {
1986       The_stub_table* stub_table = this->stub_table(i);
1987       if (!stub_table)
1988         continue;
1989       std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
1990         ipair(stub_table->find_erratum_stubs_for_input_section(this, i));
1991       Erratum_stub_set_iter p = ipair.first, end = ipair.second;
1992       typename Sized_relobj_file<size, big_endian>::View_size&
1993         pview((*pviews)[i]);
1994       AArch64_address view_offset = 0;
1995       if (pview.is_input_output_view)
1996         {
1997           // In this case, write_sections has not added the output offset to
1998           // the view's address, so we must do so. Currently this only happens
1999           // for a relaxed section.
2000           unsigned int index = this->adjust_shndx(i);
2001           const Output_relaxed_input_section* poris =
2002               out_sections[index]->find_relaxed_input_section(this, index);
2003           gold_assert(poris != NULL);
2004           view_offset = poris->address() - pview.address;
2005         }
2006
2007       while (p != end)
2008         {
2009           The_erratum_stub* stub = *p;
2010
2011           // Double check data before fix.
2012           gold_assert(pview.address + view_offset + stub->sh_offset()
2013                       == stub->erratum_address());
2014
2015           // Update previously recorded erratum insn with relocated
2016           // version.
2017           Insntype* ip =
2018             reinterpret_cast<Insntype*>(
2019               pview.view + view_offset + stub->sh_offset());
2020           Insntype insn_to_fix = ip[0];
2021           stub->update_erratum_insn(insn_to_fix);
2022
2023           // First try to see if erratum is 843419 and if it can be fixed
2024           // without using branch-to-stub.
2025           if (!try_fix_erratum_843419_optimized(stub, view_offset, pview))
2026             {
2027               // Replace the erratum insn with a branch-to-stub.
2028               AArch64_address stub_address =
2029                 stub_table->erratum_stub_address(stub);
2030               unsigned int b_offset = stub_address - stub->erratum_address();
2031               AArch64_relocate_functions<size, big_endian>::construct_b(
2032                 pview.view + view_offset + stub->sh_offset(),
2033                 b_offset & 0xfffffff);
2034             }
2035
2036           // Erratum fix is done (or skipped), continue to relocate erratum
2037           // stub. Note, when erratum fix is skipped (either because we
2038           // proactively change the code sequence or the code sequence is
2039           // changed by relaxation, etc), we can still safely relocate the
2040           // erratum stub, ignoring the fact the erratum could never be
2041           // executed.
2042           stub_table->relocate_erratum_stub(
2043             stub,
2044             pview.view + view_offset + (stub_table->address() - pview.address));
2045
2046           // Next erratum stub.
2047           ++p;
2048         }
2049     }
2050 }
2051
2052
2053 // This is an optimization for 843419. This erratum requires the sequence begin
2054 // with 'adrp', when final value calculated by adrp fits in adr, we can just
2055 // replace 'adrp' with 'adr', so we save 2 jumps per occurrence. (Note, however,
2056 // in this case, we do not delete the erratum stub (too late to do so), it is
2057 // merely generated without ever being called.)
2058
2059 template<int size, bool big_endian>
2060 bool
2061 AArch64_relobj<size, big_endian>::try_fix_erratum_843419_optimized(
2062     The_erratum_stub* stub, AArch64_address view_offset,
2063     typename Sized_relobj_file<size, big_endian>::View_size& pview)
2064 {
2065   if (stub->type() != ST_E_843419)
2066     return false;
2067
2068   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
2069   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
2070   E843419_stub<size, big_endian>* e843419_stub =
2071     reinterpret_cast<E843419_stub<size, big_endian>*>(stub);
2072   AArch64_address pc =
2073     pview.address + view_offset + e843419_stub->adrp_sh_offset();
2074   unsigned int adrp_offset = e843419_stub->adrp_sh_offset ();
2075   Insntype* adrp_view =
2076     reinterpret_cast<Insntype*>(pview.view + view_offset + adrp_offset);
2077   Insntype adrp_insn = adrp_view[0];
2078
2079   // If the instruction at adrp_sh_offset is "mrs R, tpidr_el0", it may come
2080   // from IE -> LE relaxation etc.  This is a side-effect of TLS relaxation that
2081   // ADRP has been turned into MRS, there is no erratum risk anymore.
2082   // Therefore, we return true to avoid doing unnecessary branch-to-stub.
2083   if (Insn_utilities::is_mrs_tpidr_el0(adrp_insn))
2084     return true;
2085
2086   // If the instruction at adrp_sh_offset is not ADRP and the instruction before
2087   // it is "mrs R, tpidr_el0", it may come from LD -> LE relaxation etc.
2088   // Like the above case, there is no erratum risk any more, we can safely
2089   // return true.
2090   if (!Insn_utilities::is_adrp(adrp_insn) && adrp_offset)
2091     {
2092       Insntype* prev_view =
2093         reinterpret_cast<Insntype*>(
2094           pview.view + view_offset + adrp_offset - 4);
2095       Insntype prev_insn = prev_view[0];
2096
2097       if (Insn_utilities::is_mrs_tpidr_el0(prev_insn))
2098         return true;
2099     }
2100
2101   /* If we reach here, the first instruction must be ADRP.  */
2102   gold_assert(Insn_utilities::is_adrp(adrp_insn));
2103   // Get adrp 33-bit signed imm value.
2104   int64_t adrp_imm = Insn_utilities::
2105     aarch64_adrp_decode_imm(adrp_insn);
2106   // adrp - final value transferred to target register is calculated as:
2107   //     PC[11:0] = Zeros(12)
2108   //     adrp_dest_value = PC + adrp_imm;
2109   int64_t adrp_dest_value = (pc & ~((1 << 12) - 1)) + adrp_imm;
2110   // adr -final value transferred to target register is calucalted as:
2111   //     PC + adr_imm
2112   // So we have:
2113   //     PC + adr_imm = adrp_dest_value
2114   //   ==>
2115   //     adr_imm = adrp_dest_value - PC
2116   int64_t adr_imm = adrp_dest_value - pc;
2117   // Check if imm fits in adr (21-bit signed).
2118   if (-(1 << 20) <= adr_imm && adr_imm < (1 << 20))
2119     {
2120       // Convert 'adrp' into 'adr'.
2121       Insntype adr_insn = adrp_insn & ((1u << 31) - 1);
2122       adr_insn = Insn_utilities::
2123         aarch64_adr_encode_imm(adr_insn, adr_imm);
2124       elfcpp::Swap<32, big_endian>::writeval(adrp_view, adr_insn);
2125       return true;
2126     }
2127   return false;
2128 }
2129
2130
2131 // Relocate sections.
2132
2133 template<int size, bool big_endian>
2134 void
2135 AArch64_relobj<size, big_endian>::do_relocate_sections(
2136     const Symbol_table* symtab, const Layout* layout,
2137     const unsigned char* pshdrs, Output_file* of,
2138     typename Sized_relobj_file<size, big_endian>::Views* pviews)
2139 {
2140   // Relocate the section data.
2141   this->relocate_section_range(symtab, layout, pshdrs, of, pviews,
2142                                1, this->shnum() - 1);
2143
2144   // We do not generate stubs if doing a relocatable link.
2145   if (parameters->options().relocatable())
2146     return;
2147
2148   // This part only relocates erratum stubs that belong to input sections of this
2149   // object file.
2150   if (parameters->options().fix_cortex_a53_843419()
2151       || parameters->options().fix_cortex_a53_835769())
2152     this->fix_errata_and_relocate_erratum_stubs(pviews);
2153
2154   Relocate_info<size, big_endian> relinfo;
2155   relinfo.symtab = symtab;
2156   relinfo.layout = layout;
2157   relinfo.object = this;
2158
2159   // This part relocates all reloc stubs that are contained in stub_tables of
2160   // this object file.
2161   unsigned int shnum = this->shnum();
2162   The_target_aarch64* target = The_target_aarch64::current_target();
2163
2164   for (unsigned int i = 1; i < shnum; ++i)
2165     {
2166       The_aarch64_input_section* aarch64_input_section =
2167           target->find_aarch64_input_section(this, i);
2168       if (aarch64_input_section != NULL
2169           && aarch64_input_section->is_stub_table_owner()
2170           && !aarch64_input_section->stub_table()->empty())
2171         {
2172           Output_section* os = this->output_section(i);
2173           gold_assert(os != NULL);
2174
2175           relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
2176           relinfo.reloc_shdr = NULL;
2177           relinfo.data_shndx = i;
2178           relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<size>::shdr_size;
2179
2180           typename Sized_relobj_file<size, big_endian>::View_size&
2181               view_struct = (*pviews)[i];
2182           gold_assert(view_struct.view != NULL);
2183
2184           The_stub_table* stub_table = aarch64_input_section->stub_table();
2185           off_t offset = stub_table->address() - view_struct.address;
2186           unsigned char* view = view_struct.view + offset;
2187           AArch64_address address = stub_table->address();
2188           section_size_type view_size = stub_table->data_size();
2189           stub_table->relocate_reloc_stubs(&relinfo, target, os, view, address,
2190                                            view_size);
2191         }
2192     }
2193 }
2194
2195
2196 // Determine if an input section is scannable for stub processing.  SHDR is
2197 // the header of the section and SHNDX is the section index.  OS is the output
2198 // section for the input section and SYMTAB is the global symbol table used to
2199 // look up ICF information.
2200
2201 template<int size, bool big_endian>
2202 bool
2203 AArch64_relobj<size, big_endian>::text_section_is_scannable(
2204     const elfcpp::Shdr<size, big_endian>& text_shdr,
2205     unsigned int text_shndx,
2206     const Output_section* os,
2207     const Symbol_table* symtab)
2208 {
2209   // Skip any empty sections, unallocated sections or sections whose
2210   // type are not SHT_PROGBITS.
2211   if (text_shdr.get_sh_size() == 0
2212       || (text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
2213       || text_shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
2214     return false;
2215
2216   // Skip any discarded or ICF'ed sections.
2217   if (os == NULL || symtab->is_section_folded(this, text_shndx))
2218     return false;
2219
2220   // Skip exception frame.
2221   if (strcmp(os->name(), ".eh_frame") == 0)
2222     return false ;
2223
2224   gold_assert(!this->is_output_section_offset_invalid(text_shndx) ||
2225               os->find_relaxed_input_section(this, text_shndx) != NULL);
2226
2227   return true;
2228 }
2229
2230
2231 // Determine if we want to scan the SHNDX-th section for relocation stubs.
2232 // This is a helper for AArch64_relobj::scan_sections_for_stubs().
2233
2234 template<int size, bool big_endian>
2235 bool
2236 AArch64_relobj<size, big_endian>::section_needs_reloc_stub_scanning(
2237     const elfcpp::Shdr<size, big_endian>& shdr,
2238     const Relobj::Output_sections& out_sections,
2239     const Symbol_table* symtab,
2240     const unsigned char* pshdrs)
2241 {
2242   unsigned int sh_type = shdr.get_sh_type();
2243   if (sh_type != elfcpp::SHT_RELA)
2244     return false;
2245
2246   // Ignore empty section.
2247   off_t sh_size = shdr.get_sh_size();
2248   if (sh_size == 0)
2249     return false;
2250
2251   // Ignore reloc section with unexpected symbol table.  The
2252   // error will be reported in the final link.
2253   if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
2254     return false;
2255
2256   gold_assert(sh_type == elfcpp::SHT_RELA);
2257   unsigned int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
2258
2259   // Ignore reloc section with unexpected entsize or uneven size.
2260   // The error will be reported in the final link.
2261   if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
2262     return false;
2263
2264   // Ignore reloc section with bad info.  This error will be
2265   // reported in the final link.
2266   unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_info());
2267   if (text_shndx >= this->shnum())
2268     return false;
2269
2270   const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
2271   const elfcpp::Shdr<size, big_endian> text_shdr(pshdrs +
2272                                                  text_shndx * shdr_size);
2273   return this->text_section_is_scannable(text_shdr, text_shndx,
2274                                          out_sections[text_shndx], symtab);
2275 }
2276
2277
2278 // Scan section SHNDX for erratum 843419 and 835769.
2279
2280 template<int size, bool big_endian>
2281 void
2282 AArch64_relobj<size, big_endian>::scan_errata(
2283     unsigned int shndx, const elfcpp::Shdr<size, big_endian>& shdr,
2284     Output_section* os, const Symbol_table* symtab,
2285     The_target_aarch64* target)
2286 {
2287   if (shdr.get_sh_size() == 0
2288       || (shdr.get_sh_flags() &
2289           (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR)) == 0
2290       || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
2291     return;
2292
2293   if (!os || symtab->is_section_folded(this, shndx)) return;
2294
2295   AArch64_address output_offset = this->get_output_section_offset(shndx);
2296   AArch64_address output_address;
2297   if (output_offset != invalid_address)
2298     output_address = os->address() + output_offset;
2299   else
2300     {
2301       const Output_relaxed_input_section* poris =
2302         os->find_relaxed_input_section(this, shndx);
2303       if (!poris) return;
2304       output_address = poris->address();
2305     }
2306
2307   section_size_type input_view_size = 0;
2308   const unsigned char* input_view =
2309     this->section_contents(shndx, &input_view_size, false);
2310
2311   Mapping_symbol_position section_start(shndx, 0);
2312   // Find the first mapping symbol record within section shndx.
2313   typename Mapping_symbol_info::const_iterator p =
2314     this->mapping_symbol_info_.lower_bound(section_start);
2315   while (p != this->mapping_symbol_info_.end() &&
2316          p->first.shndx_ == shndx)
2317     {
2318       typename Mapping_symbol_info::const_iterator prev = p;
2319       ++p;
2320       if (prev->second == 'x')
2321         {
2322           section_size_type span_start =
2323             convert_to_section_size_type(prev->first.offset_);
2324           section_size_type span_end;
2325           if (p != this->mapping_symbol_info_.end()
2326               && p->first.shndx_ == shndx)
2327             span_end = convert_to_section_size_type(p->first.offset_);
2328           else
2329             span_end = convert_to_section_size_type(shdr.get_sh_size());
2330
2331           // Here we do not share the scanning code of both errata. For 843419,
2332           // only the last few insns of each page are examined, which is fast,
2333           // whereas, for 835769, every insn pair needs to be checked.
2334
2335           if (parameters->options().fix_cortex_a53_843419())
2336             target->scan_erratum_843419_span(
2337               this, shndx, span_start, span_end,
2338               const_cast<unsigned char*>(input_view), output_address);
2339
2340           if (parameters->options().fix_cortex_a53_835769())
2341             target->scan_erratum_835769_span(
2342               this, shndx, span_start, span_end,
2343               const_cast<unsigned char*>(input_view), output_address);
2344         }
2345     }
2346 }
2347
2348
2349 // Scan relocations for stub generation.
2350
2351 template<int size, bool big_endian>
2352 void
2353 AArch64_relobj<size, big_endian>::scan_sections_for_stubs(
2354     The_target_aarch64* target,
2355     const Symbol_table* symtab,
2356     const Layout* layout)
2357 {
2358   unsigned int shnum = this->shnum();
2359   const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
2360
2361   // Read the section headers.
2362   const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
2363                                                shnum * shdr_size,
2364                                                true, true);
2365
2366   // To speed up processing, we set up hash tables for fast lookup of
2367   // input offsets to output addresses.
2368   this->initialize_input_to_output_maps();
2369
2370   const Relobj::Output_sections& out_sections(this->output_sections());
2371
2372   Relocate_info<size, big_endian> relinfo;
2373   relinfo.symtab = symtab;
2374   relinfo.layout = layout;
2375   relinfo.object = this;
2376
2377   // Do relocation stubs scanning.
2378   const unsigned char* p = pshdrs + shdr_size;
2379   for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
2380     {
2381       const elfcpp::Shdr<size, big_endian> shdr(p);
2382       if (parameters->options().fix_cortex_a53_843419()
2383           || parameters->options().fix_cortex_a53_835769())
2384         scan_errata(i, shdr, out_sections[i], symtab, target);
2385       if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
2386                                                   pshdrs))
2387         {
2388           unsigned int index = this->adjust_shndx(shdr.get_sh_info());
2389           AArch64_address output_offset =
2390               this->get_output_section_offset(index);
2391           AArch64_address output_address;
2392           if (output_offset != invalid_address)
2393             {
2394               output_address = out_sections[index]->address() + output_offset;
2395             }
2396           else
2397             {
2398               // Currently this only happens for a relaxed section.
2399               const Output_relaxed_input_section* poris =
2400                   out_sections[index]->find_relaxed_input_section(this, index);
2401               gold_assert(poris != NULL);
2402               output_address = poris->address();
2403             }
2404
2405           // Get the relocations.
2406           const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
2407                                                         shdr.get_sh_size(),
2408                                                         true, false);
2409
2410           // Get the section contents.
2411           section_size_type input_view_size = 0;
2412           const unsigned char* input_view =
2413               this->section_contents(index, &input_view_size, false);
2414
2415           relinfo.reloc_shndx = i;
2416           relinfo.data_shndx = index;
2417           unsigned int sh_type = shdr.get_sh_type();
2418           unsigned int reloc_size;
2419           gold_assert (sh_type == elfcpp::SHT_RELA);
2420           reloc_size = elfcpp::Elf_sizes<size>::rela_size;
2421
2422           Output_section* os = out_sections[index];
2423           target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
2424                                          shdr.get_sh_size() / reloc_size,
2425                                          os,
2426                                          output_offset == invalid_address,
2427                                          input_view, output_address,
2428                                          input_view_size);
2429         }
2430     }
2431 }
2432
2433
2434 // A class to wrap an ordinary input section containing executable code.
2435
2436 template<int size, bool big_endian>
2437 class AArch64_input_section : public Output_relaxed_input_section
2438 {
2439  public:
2440   typedef Stub_table<size, big_endian> The_stub_table;
2441
2442   AArch64_input_section(Relobj* relobj, unsigned int shndx)
2443     : Output_relaxed_input_section(relobj, shndx, 1),
2444       stub_table_(NULL),
2445       original_contents_(NULL), original_size_(0),
2446       original_addralign_(1)
2447   { }
2448
2449   ~AArch64_input_section()
2450   { delete[] this->original_contents_; }
2451
2452   // Initialize.
2453   void
2454   init();
2455
2456   // Set the stub_table.
2457   void
2458   set_stub_table(The_stub_table* st)
2459   { this->stub_table_ = st; }
2460
2461   // Whether this is a stub table owner.
2462   bool
2463   is_stub_table_owner() const
2464   { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
2465
2466   // Return the original size of the section.
2467   uint32_t
2468   original_size() const
2469   { return this->original_size_; }
2470
2471   // Return the stub table.
2472   The_stub_table*
2473   stub_table()
2474   { return stub_table_; }
2475
2476  protected:
2477   // Write out this input section.
2478   void
2479   do_write(Output_file*);
2480
2481   // Return required alignment of this.
2482   uint64_t
2483   do_addralign() const
2484   {
2485     if (this->is_stub_table_owner())
2486       return std::max(this->stub_table_->addralign(),
2487                       static_cast<uint64_t>(this->original_addralign_));
2488     else
2489       return this->original_addralign_;
2490   }
2491
2492   // Finalize data size.
2493   void
2494   set_final_data_size();
2495
2496   // Reset address and file offset.
2497   void
2498   do_reset_address_and_file_offset();
2499
2500   // Output offset.
2501   bool
2502   do_output_offset(const Relobj* object, unsigned int shndx,
2503                    section_offset_type offset,
2504                    section_offset_type* poutput) const
2505   {
2506     if ((object == this->relobj())
2507         && (shndx == this->shndx())
2508         && (offset >= 0)
2509         && (offset <=
2510             convert_types<section_offset_type, uint32_t>(this->original_size_)))
2511       {
2512         *poutput = offset;
2513         return true;
2514       }
2515     else
2516       return false;
2517   }
2518
2519  private:
2520   // Copying is not allowed.
2521   AArch64_input_section(const AArch64_input_section&);
2522   AArch64_input_section& operator=(const AArch64_input_section&);
2523
2524   // The relocation stubs.
2525   The_stub_table* stub_table_;
2526   // Original section contents.  We have to make a copy here since the file
2527   // containing the original section may not be locked when we need to access
2528   // the contents.
2529   unsigned char* original_contents_;
2530   // Section size of the original input section.
2531   uint32_t original_size_;
2532   // Address alignment of the original input section.
2533   uint32_t original_addralign_;
2534 };  // End of AArch64_input_section
2535
2536
2537 // Finalize data size.
2538
2539 template<int size, bool big_endian>
2540 void
2541 AArch64_input_section<size, big_endian>::set_final_data_size()
2542 {
2543   off_t off = convert_types<off_t, uint64_t>(this->original_size_);
2544
2545   if (this->is_stub_table_owner())
2546     {
2547       this->stub_table_->finalize_data_size();
2548       off = align_address(off, this->stub_table_->addralign());
2549       off += this->stub_table_->data_size();
2550     }
2551   this->set_data_size(off);
2552 }
2553
2554
2555 // Reset address and file offset.
2556
2557 template<int size, bool big_endian>
2558 void
2559 AArch64_input_section<size, big_endian>::do_reset_address_and_file_offset()
2560 {
2561   // Size of the original input section contents.
2562   off_t off = convert_types<off_t, uint64_t>(this->original_size_);
2563
2564   // If this is a stub table owner, account for the stub table size.
2565   if (this->is_stub_table_owner())
2566     {
2567       The_stub_table* stub_table = this->stub_table_;
2568
2569       // Reset the stub table's address and file offset.  The
2570       // current data size for child will be updated after that.
2571       stub_table_->reset_address_and_file_offset();
2572       off = align_address(off, stub_table_->addralign());
2573       off += stub_table->current_data_size();
2574     }
2575
2576   this->set_current_data_size(off);
2577 }
2578
2579
2580 // Initialize an Arm_input_section.
2581
2582 template<int size, bool big_endian>
2583 void
2584 AArch64_input_section<size, big_endian>::init()
2585 {
2586   Relobj* relobj = this->relobj();
2587   unsigned int shndx = this->shndx();
2588
2589   // We have to cache original size, alignment and contents to avoid locking
2590   // the original file.
2591   this->original_addralign_ =
2592       convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
2593
2594   // This is not efficient but we expect only a small number of relaxed
2595   // input sections for stubs.
2596   section_size_type section_size;
2597   const unsigned char* section_contents =
2598       relobj->section_contents(shndx, &section_size, false);
2599   this->original_size_ =
2600       convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
2601
2602   gold_assert(this->original_contents_ == NULL);
2603   this->original_contents_ = new unsigned char[section_size];
2604   memcpy(this->original_contents_, section_contents, section_size);
2605
2606   // We want to make this look like the original input section after
2607   // output sections are finalized.
2608   Output_section* os = relobj->output_section(shndx);
2609   off_t offset = relobj->output_section_offset(shndx);
2610   gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
2611   this->set_address(os->address() + offset);
2612   this->set_file_offset(os->offset() + offset);
2613   this->set_current_data_size(this->original_size_);
2614   this->finalize_data_size();
2615 }
2616
2617
2618 // Write data to output file.
2619
2620 template<int size, bool big_endian>
2621 void
2622 AArch64_input_section<size, big_endian>::do_write(Output_file* of)
2623 {
2624   // We have to write out the original section content.
2625   gold_assert(this->original_contents_ != NULL);
2626   of->write(this->offset(), this->original_contents_,
2627             this->original_size_);
2628
2629   // If this owns a stub table and it is not empty, write it.
2630   if (this->is_stub_table_owner() && !this->stub_table_->empty())
2631     this->stub_table_->write(of);
2632 }
2633
2634
2635 // Arm output section class.  This is defined mainly to add a number of stub
2636 // generation methods.
2637
2638 template<int size, bool big_endian>
2639 class AArch64_output_section : public Output_section
2640 {
2641  public:
2642   typedef Target_aarch64<size, big_endian> The_target_aarch64;
2643   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
2644   typedef Stub_table<size, big_endian> The_stub_table;
2645   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
2646
2647  public:
2648   AArch64_output_section(const char* name, elfcpp::Elf_Word type,
2649                          elfcpp::Elf_Xword flags)
2650     : Output_section(name, type, flags)
2651   { }
2652
2653   ~AArch64_output_section() {}
2654
2655   // Group input sections for stub generation.
2656   void
2657   group_sections(section_size_type, bool, Target_aarch64<size, big_endian>*,
2658                  const Task*);
2659
2660  private:
2661   typedef Output_section::Input_section Input_section;
2662   typedef Output_section::Input_section_list Input_section_list;
2663
2664   // Create a stub group.
2665   void
2666   create_stub_group(Input_section_list::const_iterator,
2667                     Input_section_list::const_iterator,
2668                     Input_section_list::const_iterator,
2669                     The_target_aarch64*,
2670                     std::vector<Output_relaxed_input_section*>&,
2671                     const Task*);
2672 };  // End of AArch64_output_section
2673
2674
2675 // Create a stub group for input sections from FIRST to LAST. OWNER points to
2676 // the input section that will be the owner of the stub table.
2677
2678 template<int size, bool big_endian> void
2679 AArch64_output_section<size, big_endian>::create_stub_group(
2680     Input_section_list::const_iterator first,
2681     Input_section_list::const_iterator last,
2682     Input_section_list::const_iterator owner,
2683     The_target_aarch64* target,
2684     std::vector<Output_relaxed_input_section*>& new_relaxed_sections,
2685     const Task* task)
2686 {
2687   // Currently we convert ordinary input sections into relaxed sections only
2688   // at this point.
2689   The_aarch64_input_section* input_section;
2690   if (owner->is_relaxed_input_section())
2691     gold_unreachable();
2692   else
2693     {
2694       gold_assert(owner->is_input_section());
2695       // Create a new relaxed input section.  We need to lock the original
2696       // file.
2697       Task_lock_obj<Object> tl(task, owner->relobj());
2698       input_section =
2699           target->new_aarch64_input_section(owner->relobj(), owner->shndx());
2700       new_relaxed_sections.push_back(input_section);
2701     }
2702
2703   // Create a stub table.
2704   The_stub_table* stub_table =
2705       target->new_stub_table(input_section);
2706
2707   input_section->set_stub_table(stub_table);
2708
2709   Input_section_list::const_iterator p = first;
2710   // Look for input sections or relaxed input sections in [first ... last].
2711   do
2712     {
2713       if (p->is_input_section() || p->is_relaxed_input_section())
2714         {
2715           // The stub table information for input sections live
2716           // in their objects.
2717           The_aarch64_relobj* aarch64_relobj =
2718               static_cast<The_aarch64_relobj*>(p->relobj());
2719           aarch64_relobj->set_stub_table(p->shndx(), stub_table);
2720         }
2721     }
2722   while (p++ != last);
2723 }
2724
2725
2726 // Group input sections for stub generation. GROUP_SIZE is roughly the limit of
2727 // stub groups. We grow a stub group by adding input section until the size is
2728 // just below GROUP_SIZE. The last input section will be converted into a stub
2729 // table owner. If STUB_ALWAYS_AFTER_BRANCH is false, we also add input sectiond
2730 // after the stub table, effectively doubling the group size.
2731 //
2732 // This is similar to the group_sections() function in elf32-arm.c but is
2733 // implemented differently.
2734
2735 template<int size, bool big_endian>
2736 void AArch64_output_section<size, big_endian>::group_sections(
2737     section_size_type group_size,
2738     bool stubs_always_after_branch,
2739     Target_aarch64<size, big_endian>* target,
2740     const Task* task)
2741 {
2742   typedef enum
2743   {
2744     NO_GROUP,
2745     FINDING_STUB_SECTION,
2746     HAS_STUB_SECTION
2747   } State;
2748
2749   std::vector<Output_relaxed_input_section*> new_relaxed_sections;
2750
2751   State state = NO_GROUP;
2752   section_size_type off = 0;
2753   section_size_type group_begin_offset = 0;
2754   section_size_type group_end_offset = 0;
2755   section_size_type stub_table_end_offset = 0;
2756   Input_section_list::const_iterator group_begin =
2757       this->input_sections().end();
2758   Input_section_list::const_iterator stub_table =
2759       this->input_sections().end();
2760   Input_section_list::const_iterator group_end = this->input_sections().end();
2761   for (Input_section_list::const_iterator p = this->input_sections().begin();
2762        p != this->input_sections().end();
2763        ++p)
2764     {
2765       section_size_type section_begin_offset =
2766         align_address(off, p->addralign());
2767       section_size_type section_end_offset =
2768         section_begin_offset + p->data_size();
2769
2770       // Check to see if we should group the previously seen sections.
2771       switch (state)
2772         {
2773         case NO_GROUP:
2774           break;
2775
2776         case FINDING_STUB_SECTION:
2777           // Adding this section makes the group larger than GROUP_SIZE.
2778           if (section_end_offset - group_begin_offset >= group_size)
2779             {
2780               if (stubs_always_after_branch)
2781                 {
2782                   gold_assert(group_end != this->input_sections().end());
2783                   this->create_stub_group(group_begin, group_end, group_end,
2784                                           target, new_relaxed_sections,
2785                                           task);
2786                   state = NO_GROUP;
2787                 }
2788               else
2789                 {
2790                   // Input sections up to stub_group_size bytes after the stub
2791                   // table can be handled by it too.
2792                   state = HAS_STUB_SECTION;
2793                   stub_table = group_end;
2794                   stub_table_end_offset = group_end_offset;
2795                 }
2796             }
2797             break;
2798
2799         case HAS_STUB_SECTION:
2800           // Adding this section makes the post stub-section group larger
2801           // than GROUP_SIZE.
2802           gold_unreachable();
2803           // NOT SUPPORTED YET. For completeness only.
2804           if (section_end_offset - stub_table_end_offset >= group_size)
2805            {
2806              gold_assert(group_end != this->input_sections().end());
2807              this->create_stub_group(group_begin, group_end, stub_table,
2808                                      target, new_relaxed_sections, task);
2809              state = NO_GROUP;
2810            }
2811            break;
2812
2813           default:
2814             gold_unreachable();
2815         }
2816
2817       // If we see an input section and currently there is no group, start
2818       // a new one.  Skip any empty sections.  We look at the data size
2819       // instead of calling p->relobj()->section_size() to avoid locking.
2820       if ((p->is_input_section() || p->is_relaxed_input_section())
2821           && (p->data_size() != 0))
2822         {
2823           if (state == NO_GROUP)
2824             {
2825               state = FINDING_STUB_SECTION;
2826               group_begin = p;
2827               group_begin_offset = section_begin_offset;
2828             }
2829
2830           // Keep track of the last input section seen.
2831           group_end = p;
2832           group_end_offset = section_end_offset;
2833         }
2834
2835       off = section_end_offset;
2836     }
2837
2838   // Create a stub group for any ungrouped sections.
2839   if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
2840     {
2841       gold_assert(group_end != this->input_sections().end());
2842       this->create_stub_group(group_begin, group_end,
2843                               (state == FINDING_STUB_SECTION
2844                                ? group_end
2845                                : stub_table),
2846                               target, new_relaxed_sections, task);
2847     }
2848
2849   if (!new_relaxed_sections.empty())
2850     this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
2851
2852   // Update the section offsets
2853   for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
2854     {
2855       The_aarch64_relobj* relobj = static_cast<The_aarch64_relobj*>(
2856           new_relaxed_sections[i]->relobj());
2857       unsigned int shndx = new_relaxed_sections[i]->shndx();
2858       // Tell AArch64_relobj that this input section is converted.
2859       relobj->convert_input_section_to_relaxed_section(shndx);
2860     }
2861 }  // End of AArch64_output_section::group_sections
2862
2863
2864 AArch64_reloc_property_table* aarch64_reloc_property_table = NULL;
2865
2866
2867 // The aarch64 target class.
2868 // See the ABI at
2869 // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf
2870 template<int size, bool big_endian>
2871 class Target_aarch64 : public Sized_target<size, big_endian>
2872 {
2873  public:
2874   typedef Target_aarch64<size, big_endian> This;
2875   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
2876       Reloc_section;
2877   typedef Relocate_info<size, big_endian> The_relocate_info;
2878   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
2879   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
2880   typedef Reloc_stub<size, big_endian> The_reloc_stub;
2881   typedef Erratum_stub<size, big_endian> The_erratum_stub;
2882   typedef typename Reloc_stub<size, big_endian>::Key The_reloc_stub_key;
2883   typedef Stub_table<size, big_endian> The_stub_table;
2884   typedef std::vector<The_stub_table*> Stub_table_list;
2885   typedef typename Stub_table_list::iterator Stub_table_iterator;
2886   typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
2887   typedef AArch64_output_section<size, big_endian> The_aarch64_output_section;
2888   typedef Unordered_map<Section_id,
2889                         AArch64_input_section<size, big_endian>*,
2890                         Section_id_hash> AArch64_input_section_map;
2891   typedef AArch64_insn_utilities<big_endian> Insn_utilities;
2892   const static int TCB_SIZE = size / 8 * 2;
2893
2894   Target_aarch64(const Target::Target_info* info = &aarch64_info)
2895     : Sized_target<size, big_endian>(info),
2896       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
2897       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
2898       rela_irelative_(NULL), copy_relocs_(elfcpp::R_AARCH64_COPY),
2899       got_mod_index_offset_(-1U),
2900       tlsdesc_reloc_info_(), tls_base_symbol_defined_(false),
2901       stub_tables_(), stub_group_size_(0), aarch64_input_section_map_()
2902   { }
2903
2904   // Scan the relocations to determine unreferenced sections for
2905   // garbage collection.
2906   void
2907   gc_process_relocs(Symbol_table* symtab,
2908                     Layout* layout,
2909                     Sized_relobj_file<size, big_endian>* object,
2910                     unsigned int data_shndx,
2911                     unsigned int sh_type,
2912                     const unsigned char* prelocs,
2913                     size_t reloc_count,
2914                     Output_section* output_section,
2915                     bool needs_special_offset_handling,
2916                     size_t local_symbol_count,
2917                     const unsigned char* plocal_symbols);
2918
2919   // Scan the relocations to look for symbol adjustments.
2920   void
2921   scan_relocs(Symbol_table* symtab,
2922               Layout* layout,
2923               Sized_relobj_file<size, big_endian>* object,
2924               unsigned int data_shndx,
2925               unsigned int sh_type,
2926               const unsigned char* prelocs,
2927               size_t reloc_count,
2928               Output_section* output_section,
2929               bool needs_special_offset_handling,
2930               size_t local_symbol_count,
2931               const unsigned char* plocal_symbols);
2932
2933   // Finalize the sections.
2934   void
2935   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2936
2937   // Return the value to use for a dynamic which requires special
2938   // treatment.
2939   uint64_t
2940   do_dynsym_value(const Symbol*) const;
2941
2942   // Relocate a section.
2943   void
2944   relocate_section(const Relocate_info<size, big_endian>*,
2945                    unsigned int sh_type,
2946                    const unsigned char* prelocs,
2947                    size_t reloc_count,
2948                    Output_section* output_section,
2949                    bool needs_special_offset_handling,
2950                    unsigned char* view,
2951                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
2952                    section_size_type view_size,
2953                    const Reloc_symbol_changes*);
2954
2955   // Scan the relocs during a relocatable link.
2956   void
2957   scan_relocatable_relocs(Symbol_table* symtab,
2958                           Layout* layout,
2959                           Sized_relobj_file<size, big_endian>* object,
2960                           unsigned int data_shndx,
2961                           unsigned int sh_type,
2962                           const unsigned char* prelocs,
2963                           size_t reloc_count,
2964                           Output_section* output_section,
2965                           bool needs_special_offset_handling,
2966                           size_t local_symbol_count,
2967                           const unsigned char* plocal_symbols,
2968                           Relocatable_relocs*);
2969
2970   // Scan the relocs for --emit-relocs.
2971   void
2972   emit_relocs_scan(Symbol_table* symtab,
2973                    Layout* layout,
2974                    Sized_relobj_file<size, big_endian>* object,
2975                    unsigned int data_shndx,
2976                    unsigned int sh_type,
2977                    const unsigned char* prelocs,
2978                    size_t reloc_count,
2979                    Output_section* output_section,
2980                    bool needs_special_offset_handling,
2981                    size_t local_symbol_count,
2982                    const unsigned char* plocal_syms,
2983                    Relocatable_relocs* rr);
2984
2985   // Relocate a section during a relocatable link.
2986   void
2987   relocate_relocs(
2988       const Relocate_info<size, big_endian>*,
2989       unsigned int sh_type,
2990       const unsigned char* prelocs,
2991       size_t reloc_count,
2992       Output_section* output_section,
2993       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
2994       unsigned char* view,
2995       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
2996       section_size_type view_size,
2997       unsigned char* reloc_view,
2998       section_size_type reloc_view_size);
2999
3000   // Return the symbol index to use for a target specific relocation.
3001   // The only target specific relocation is R_AARCH64_TLSDESC for a
3002   // local symbol, which is an absolute reloc.
3003   unsigned int
3004   do_reloc_symbol_index(void*, unsigned int r_type) const
3005   {
3006     gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
3007     return 0;
3008   }
3009
3010   // Return the addend to use for a target specific relocation.
3011   uint64_t
3012   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
3013
3014   // Return the PLT section.
3015   uint64_t
3016   do_plt_address_for_global(const Symbol* gsym) const
3017   { return this->plt_section()->address_for_global(gsym); }
3018
3019   uint64_t
3020   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
3021   { return this->plt_section()->address_for_local(relobj, symndx); }
3022
3023   // This function should be defined in targets that can use relocation
3024   // types to determine (implemented in local_reloc_may_be_function_pointer
3025   // and global_reloc_may_be_function_pointer)
3026   // if a function's pointer is taken.  ICF uses this in safe mode to only
3027   // fold those functions whose pointer is defintely not taken.
3028   bool
3029   do_can_check_for_function_pointers() const
3030   { return true; }
3031
3032   // Return the number of entries in the PLT.
3033   unsigned int
3034   plt_entry_count() const;
3035
3036   //Return the offset of the first non-reserved PLT entry.
3037   unsigned int
3038   first_plt_entry_offset() const;
3039
3040   // Return the size of each PLT entry.
3041   unsigned int
3042   plt_entry_size() const;
3043
3044   // Create a stub table.
3045   The_stub_table*
3046   new_stub_table(The_aarch64_input_section*);
3047
3048   // Create an aarch64 input section.
3049   The_aarch64_input_section*
3050   new_aarch64_input_section(Relobj*, unsigned int);
3051
3052   // Find an aarch64 input section instance for a given OBJ and SHNDX.
3053   The_aarch64_input_section*
3054   find_aarch64_input_section(Relobj*, unsigned int) const;
3055
3056   // Return the thread control block size.
3057   unsigned int
3058   tcb_size() const { return This::TCB_SIZE; }
3059
3060   // Scan a section for stub generation.
3061   void
3062   scan_section_for_stubs(const Relocate_info<size, big_endian>*, unsigned int,
3063                          const unsigned char*, size_t, Output_section*,
3064                          bool, const unsigned char*,
3065                          Address,
3066                          section_size_type);
3067
3068   // Scan a relocation section for stub.
3069   template<int sh_type>
3070   void
3071   scan_reloc_section_for_stubs(
3072       const The_relocate_info* relinfo,
3073       const unsigned char* prelocs,
3074       size_t reloc_count,
3075       Output_section* output_section,
3076       bool needs_special_offset_handling,
3077       const unsigned char* view,
3078       Address view_address,
3079       section_size_type);
3080
3081   // Relocate a single reloc stub.
3082   void
3083   relocate_reloc_stub(The_reloc_stub*, const Relocate_info<size, big_endian>*,
3084                       Output_section*, unsigned char*, Address,
3085                       section_size_type);
3086
3087   // Get the default AArch64 target.
3088   static This*
3089   current_target()
3090   {
3091     gold_assert(parameters->target().machine_code() == elfcpp::EM_AARCH64
3092                 && parameters->target().get_size() == size
3093                 && parameters->target().is_big_endian() == big_endian);
3094     return static_cast<This*>(parameters->sized_target<size, big_endian>());
3095   }
3096
3097
3098   // Scan erratum 843419 for a part of a section.
3099   void
3100   scan_erratum_843419_span(
3101     AArch64_relobj<size, big_endian>*,
3102     unsigned int,
3103     const section_size_type,
3104     const section_size_type,
3105     unsigned char*,
3106     Address);
3107
3108   // Scan erratum 835769 for a part of a section.
3109   void
3110   scan_erratum_835769_span(
3111     AArch64_relobj<size, big_endian>*,
3112     unsigned int,
3113     const section_size_type,
3114     const section_size_type,
3115     unsigned char*,
3116     Address);
3117
3118  protected:
3119   void
3120   do_select_as_default_target()
3121   {
3122     gold_assert(aarch64_reloc_property_table == NULL);
3123     aarch64_reloc_property_table = new AArch64_reloc_property_table();
3124   }
3125
3126   // Add a new reloc argument, returning the index in the vector.
3127   size_t
3128   add_tlsdesc_info(Sized_relobj_file<size, big_endian>* object,
3129                    unsigned int r_sym)
3130   {
3131     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
3132     return this->tlsdesc_reloc_info_.size() - 1;
3133   }
3134
3135   virtual Output_data_plt_aarch64<size, big_endian>*
3136   do_make_data_plt(Layout* layout,
3137                    Output_data_got_aarch64<size, big_endian>* got,
3138                    Output_data_space* got_plt,
3139                    Output_data_space* got_irelative)
3140   {
3141     return new Output_data_plt_aarch64_standard<size, big_endian>(
3142       layout, got, got_plt, got_irelative);
3143   }
3144
3145
3146   // do_make_elf_object to override the same function in the base class.
3147   Object*
3148   do_make_elf_object(const std::string&, Input_file*, off_t,
3149                      const elfcpp::Ehdr<size, big_endian>&);
3150
3151   Output_data_plt_aarch64<size, big_endian>*
3152   make_data_plt(Layout* layout,
3153                 Output_data_got_aarch64<size, big_endian>* got,
3154                 Output_data_space* got_plt,
3155                 Output_data_space* got_irelative)
3156   {
3157     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
3158   }
3159
3160   // We only need to generate stubs, and hence perform relaxation if we are
3161   // not doing relocatable linking.
3162   virtual bool
3163   do_may_relax() const
3164   { return !parameters->options().relocatable(); }
3165
3166   // Relaxation hook.  This is where we do stub generation.
3167   virtual bool
3168   do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*);
3169
3170   void
3171   group_sections(Layout* layout,
3172                  section_size_type group_size,
3173                  bool stubs_always_after_branch,
3174                  const Task* task);
3175
3176   void
3177   scan_reloc_for_stub(const The_relocate_info*, unsigned int,
3178                       const Sized_symbol<size>*, unsigned int,
3179                       const Symbol_value<size>*,
3180                       typename elfcpp::Elf_types<size>::Elf_Swxword,
3181                       Address Elf_Addr);
3182
3183   // Make an output section.
3184   Output_section*
3185   do_make_output_section(const char* name, elfcpp::Elf_Word type,
3186                          elfcpp::Elf_Xword flags)
3187   { return new The_aarch64_output_section(name, type, flags); }
3188
3189  private:
3190   // The class which scans relocations.
3191   class Scan
3192   {
3193   public:
3194     Scan()
3195       : issued_non_pic_error_(false)
3196     { }
3197
3198     inline void
3199     local(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
3200           Sized_relobj_file<size, big_endian>* object,
3201           unsigned int data_shndx,
3202           Output_section* output_section,
3203           const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
3204           const elfcpp::Sym<size, big_endian>& lsym,
3205           bool is_discarded);
3206
3207     inline void
3208     global(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
3209            Sized_relobj_file<size, big_endian>* object,
3210            unsigned int data_shndx,
3211            Output_section* output_section,
3212            const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
3213            Symbol* gsym);
3214
3215     inline bool
3216     local_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
3217                                         Target_aarch64<size, big_endian>* ,
3218                                         Sized_relobj_file<size, big_endian>* ,
3219                                         unsigned int ,
3220                                         Output_section* ,
3221                                         const elfcpp::Rela<size, big_endian>& ,
3222                                         unsigned int r_type,
3223                                         const elfcpp::Sym<size, big_endian>&);
3224
3225     inline bool
3226     global_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
3227                                          Target_aarch64<size, big_endian>* ,
3228                                          Sized_relobj_file<size, big_endian>* ,
3229                                          unsigned int ,
3230                                          Output_section* ,
3231                                          const elfcpp::Rela<size, big_endian>& ,
3232                                          unsigned int r_type,
3233                                          Symbol* gsym);
3234
3235   private:
3236     static void
3237     unsupported_reloc_local(Sized_relobj_file<size, big_endian>*,
3238                             unsigned int r_type);
3239
3240     static void
3241     unsupported_reloc_global(Sized_relobj_file<size, big_endian>*,
3242                              unsigned int r_type, Symbol*);
3243
3244     inline bool
3245     possible_function_pointer_reloc(unsigned int r_type);
3246
3247     void
3248     check_non_pic(Relobj*, unsigned int r_type);
3249
3250     bool
3251     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, big_endian>*,
3252                               unsigned int r_type);
3253
3254     // Whether we have issued an error about a non-PIC compilation.
3255     bool issued_non_pic_error_;
3256   };
3257
3258   // The class which implements relocation.
3259   class Relocate
3260   {
3261    public:
3262     Relocate()
3263       : skip_call_tls_get_addr_(false)
3264     { }
3265
3266     ~Relocate()
3267     { }
3268
3269     // Do a relocation.  Return false if the caller should not issue
3270     // any warnings about this relocation.
3271     inline bool
3272     relocate(const Relocate_info<size, big_endian>*, unsigned int,
3273              Target_aarch64*, Output_section*, size_t, const unsigned char*,
3274              const Sized_symbol<size>*, const Symbol_value<size>*,
3275              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
3276              section_size_type);
3277
3278   private:
3279     inline typename AArch64_relocate_functions<size, big_endian>::Status
3280     relocate_tls(const Relocate_info<size, big_endian>*,
3281                  Target_aarch64<size, big_endian>*,
3282                  size_t,
3283                  const elfcpp::Rela<size, big_endian>&,
3284                  unsigned int r_type, const Sized_symbol<size>*,
3285                  const Symbol_value<size>*,
3286                  unsigned char*,
3287                  typename elfcpp::Elf_types<size>::Elf_Addr);
3288
3289     inline typename AArch64_relocate_functions<size, big_endian>::Status
3290     tls_gd_to_le(
3291                  const Relocate_info<size, big_endian>*,
3292                  Target_aarch64<size, big_endian>*,
3293                  const elfcpp::Rela<size, big_endian>&,
3294                  unsigned int,
3295                  unsigned char*,
3296                  const Symbol_value<size>*);
3297
3298     inline typename AArch64_relocate_functions<size, big_endian>::Status
3299     tls_ld_to_le(
3300                  const Relocate_info<size, big_endian>*,
3301                  Target_aarch64<size, big_endian>*,
3302                  const elfcpp::Rela<size, big_endian>&,
3303                  unsigned int,
3304                  unsigned char*,
3305                  const Symbol_value<size>*);
3306
3307     inline typename AArch64_relocate_functions<size, big_endian>::Status
3308     tls_ie_to_le(
3309                  const Relocate_info<size, big_endian>*,
3310                  Target_aarch64<size, big_endian>*,
3311                  const elfcpp::Rela<size, big_endian>&,
3312                  unsigned int,
3313                  unsigned char*,
3314                  const Symbol_value<size>*);
3315
3316     inline typename AArch64_relocate_functions<size, big_endian>::Status
3317     tls_desc_gd_to_le(
3318                  const Relocate_info<size, big_endian>*,
3319                  Target_aarch64<size, big_endian>*,
3320                  const elfcpp::Rela<size, big_endian>&,
3321                  unsigned int,
3322                  unsigned char*,
3323                  const Symbol_value<size>*);
3324
3325     inline typename AArch64_relocate_functions<size, big_endian>::Status
3326     tls_desc_gd_to_ie(
3327                  const Relocate_info<size, big_endian>*,
3328                  Target_aarch64<size, big_endian>*,
3329                  const elfcpp::Rela<size, big_endian>&,
3330                  unsigned int,
3331                  unsigned char*,
3332                  const Symbol_value<size>*,
3333                  typename elfcpp::Elf_types<size>::Elf_Addr,
3334                  typename elfcpp::Elf_types<size>::Elf_Addr);
3335
3336     bool skip_call_tls_get_addr_;
3337
3338   };  // End of class Relocate
3339
3340   // Adjust TLS relocation type based on the options and whether this
3341   // is a local symbol.
3342   static tls::Tls_optimization
3343   optimize_tls_reloc(bool is_final, int r_type);
3344
3345   // Get the GOT section, creating it if necessary.
3346   Output_data_got_aarch64<size, big_endian>*
3347   got_section(Symbol_table*, Layout*);
3348
3349   // Get the GOT PLT section.
3350   Output_data_space*
3351   got_plt_section() const
3352   {
3353     gold_assert(this->got_plt_ != NULL);
3354     return this->got_plt_;
3355   }
3356
3357   // Get the GOT section for TLSDESC entries.
3358   Output_data_got<size, big_endian>*
3359   got_tlsdesc_section() const
3360   {
3361     gold_assert(this->got_tlsdesc_ != NULL);
3362     return this->got_tlsdesc_;
3363   }
3364
3365   // Create the PLT section.
3366   void
3367   make_plt_section(Symbol_table* symtab, Layout* layout);
3368
3369   // Create a PLT entry for a global symbol.
3370   void
3371   make_plt_entry(Symbol_table*, Layout*, Symbol*);
3372
3373   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
3374   void
3375   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
3376                              Sized_relobj_file<size, big_endian>* relobj,
3377                              unsigned int local_sym_index);
3378
3379   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
3380   void
3381   define_tls_base_symbol(Symbol_table*, Layout*);
3382
3383   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
3384   void
3385   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
3386
3387   // Create a GOT entry for the TLS module index.
3388   unsigned int
3389   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
3390                       Sized_relobj_file<size, big_endian>* object);
3391
3392   // Get the PLT section.
3393   Output_data_plt_aarch64<size, big_endian>*
3394   plt_section() const
3395   {
3396     gold_assert(this->plt_ != NULL);
3397     return this->plt_;
3398   }
3399
3400   // Helper method to create erratum stubs for ST_E_843419 and ST_E_835769. For
3401   // ST_E_843419, we need an additional field for adrp offset.
3402   void create_erratum_stub(
3403     AArch64_relobj<size, big_endian>* relobj,
3404     unsigned int shndx,
3405     section_size_type erratum_insn_offset,
3406     Address erratum_address,
3407     typename Insn_utilities::Insntype erratum_insn,
3408     int erratum_type,
3409     unsigned int e843419_adrp_offset=0);
3410
3411   // Return whether this is a 3-insn erratum sequence.
3412   bool is_erratum_843419_sequence(
3413       typename elfcpp::Swap<32,big_endian>::Valtype insn1,
3414       typename elfcpp::Swap<32,big_endian>::Valtype insn2,
3415       typename elfcpp::Swap<32,big_endian>::Valtype insn3);
3416
3417   // Return whether this is a 835769 sequence.
3418   // (Similarly implemented as in elfnn-aarch64.c.)
3419   bool is_erratum_835769_sequence(
3420       typename elfcpp::Swap<32,big_endian>::Valtype,
3421       typename elfcpp::Swap<32,big_endian>::Valtype);
3422
3423   // Get the dynamic reloc section, creating it if necessary.
3424   Reloc_section*
3425   rela_dyn_section(Layout*);
3426
3427   // Get the section to use for TLSDESC relocations.
3428   Reloc_section*
3429   rela_tlsdesc_section(Layout*) const;
3430
3431   // Get the section to use for IRELATIVE relocations.
3432   Reloc_section*
3433   rela_irelative_section(Layout*);
3434
3435   // Add a potential copy relocation.
3436   void
3437   copy_reloc(Symbol_table* symtab, Layout* layout,
3438              Sized_relobj_file<size, big_endian>* object,
3439              unsigned int shndx, Output_section* output_section,
3440              Symbol* sym, const elfcpp::Rela<size, big_endian>& reloc)
3441   {
3442     unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
3443     this->copy_relocs_.copy_reloc(symtab, layout,
3444                                   symtab->get_sized_symbol<size>(sym),
3445                                   object, shndx, output_section,
3446                                   r_type, reloc.get_r_offset(),
3447                                   reloc.get_r_addend(),
3448                                   this->rela_dyn_section(layout));
3449   }
3450
3451   // Information about this specific target which we pass to the
3452   // general Target structure.
3453   static const Target::Target_info aarch64_info;
3454
3455   // The types of GOT entries needed for this platform.
3456   // These values are exposed to the ABI in an incremental link.
3457   // Do not renumber existing values without changing the version
3458   // number of the .gnu_incremental_inputs section.
3459   enum Got_type
3460   {
3461     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
3462     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
3463     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
3464     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
3465   };
3466
3467   // This type is used as the argument to the target specific
3468   // relocation routines.  The only target specific reloc is
3469   // R_AARCh64_TLSDESC against a local symbol.
3470   struct Tlsdesc_info
3471   {
3472     Tlsdesc_info(Sized_relobj_file<size, big_endian>* a_object,
3473                  unsigned int a_r_sym)
3474       : object(a_object), r_sym(a_r_sym)
3475     { }
3476
3477     // The object in which the local symbol is defined.
3478     Sized_relobj_file<size, big_endian>* object;
3479     // The local symbol index in the object.
3480     unsigned int r_sym;
3481   };
3482
3483   // The GOT section.
3484   Output_data_got_aarch64<size, big_endian>* got_;
3485   // The PLT section.
3486   Output_data_plt_aarch64<size, big_endian>* plt_;
3487   // The GOT PLT section.
3488   Output_data_space* got_plt_;
3489   // The GOT section for IRELATIVE relocations.
3490   Output_data_space* got_irelative_;
3491   // The GOT section for TLSDESC relocations.
3492   Output_data_got<size, big_endian>* got_tlsdesc_;
3493   // The _GLOBAL_OFFSET_TABLE_ symbol.
3494   Symbol* global_offset_table_;
3495   // The dynamic reloc section.
3496   Reloc_section* rela_dyn_;
3497   // The section to use for IRELATIVE relocs.
3498   Reloc_section* rela_irelative_;
3499   // Relocs saved to avoid a COPY reloc.
3500   Copy_relocs<elfcpp::SHT_RELA, size, big_endian> copy_relocs_;
3501   // Offset of the GOT entry for the TLS module index.
3502   unsigned int got_mod_index_offset_;
3503   // We handle R_AARCH64_TLSDESC against a local symbol as a target
3504   // specific relocation. Here we store the object and local symbol
3505   // index for the relocation.
3506   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
3507   // True if the _TLS_MODULE_BASE_ symbol has been defined.
3508   bool tls_base_symbol_defined_;
3509   // List of stub_tables
3510   Stub_table_list stub_tables_;
3511   // Actual stub group size
3512   section_size_type stub_group_size_;
3513   AArch64_input_section_map aarch64_input_section_map_;
3514 };  // End of Target_aarch64
3515
3516
3517 template<>
3518 const Target::Target_info Target_aarch64<64, false>::aarch64_info =
3519 {
3520   64,                   // size
3521   false,                // is_big_endian
3522   elfcpp::EM_AARCH64,   // machine_code
3523   false,                // has_make_symbol
3524   false,                // has_resolve
3525   false,                // has_code_fill
3526   false,                // is_default_stack_executable
3527   true,                 // can_icf_inline_merge_sections
3528   '\0',                 // wrap_char
3529   "/lib/ld.so.1",       // program interpreter
3530   0x400000,             // default_text_segment_address
3531   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3532   0x1000,               // common_pagesize (overridable by -z common-page-size)
3533   false,                // isolate_execinstr
3534   0,                    // rosegment_gap
3535   elfcpp::SHN_UNDEF,    // small_common_shndx
3536   elfcpp::SHN_UNDEF,    // large_common_shndx
3537   0,                    // small_common_section_flags
3538   0,                    // large_common_section_flags
3539   NULL,                 // attributes_section
3540   NULL,                 // attributes_vendor
3541   "_start",             // entry_symbol_name
3542   32,                   // hash_entry_size
3543 };
3544
3545 template<>
3546 const Target::Target_info Target_aarch64<32, false>::aarch64_info =
3547 {
3548   32,                   // size
3549   false,                // is_big_endian
3550   elfcpp::EM_AARCH64,   // machine_code
3551   false,                // has_make_symbol
3552   false,                // has_resolve
3553   false,                // has_code_fill
3554   false,                // is_default_stack_executable
3555   false,                // can_icf_inline_merge_sections
3556   '\0',                 // wrap_char
3557   "/lib/ld.so.1",       // program interpreter
3558   0x400000,             // default_text_segment_address
3559   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3560   0x1000,               // common_pagesize (overridable by -z common-page-size)
3561   false,                // isolate_execinstr
3562   0,                    // rosegment_gap
3563   elfcpp::SHN_UNDEF,    // small_common_shndx
3564   elfcpp::SHN_UNDEF,    // large_common_shndx
3565   0,                    // small_common_section_flags
3566   0,                    // large_common_section_flags
3567   NULL,                 // attributes_section
3568   NULL,                 // attributes_vendor
3569   "_start",             // entry_symbol_name
3570   32,                   // hash_entry_size
3571 };
3572
3573 template<>
3574 const Target::Target_info Target_aarch64<64, true>::aarch64_info =
3575 {
3576   64,                   // size
3577   true,                 // is_big_endian
3578   elfcpp::EM_AARCH64,   // machine_code
3579   false,                // has_make_symbol
3580   false,                // has_resolve
3581   false,                // has_code_fill
3582   false,                // is_default_stack_executable
3583   true,                 // can_icf_inline_merge_sections
3584   '\0',                 // wrap_char
3585   "/lib/ld.so.1",       // program interpreter
3586   0x400000,             // default_text_segment_address
3587   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3588   0x1000,               // common_pagesize (overridable by -z common-page-size)
3589   false,                // isolate_execinstr
3590   0,                    // rosegment_gap
3591   elfcpp::SHN_UNDEF,    // small_common_shndx
3592   elfcpp::SHN_UNDEF,    // large_common_shndx
3593   0,                    // small_common_section_flags
3594   0,                    // large_common_section_flags
3595   NULL,                 // attributes_section
3596   NULL,                 // attributes_vendor
3597   "_start",             // entry_symbol_name
3598   32,                   // hash_entry_size
3599 };
3600
3601 template<>
3602 const Target::Target_info Target_aarch64<32, true>::aarch64_info =
3603 {
3604   32,                   // size
3605   true,                 // is_big_endian
3606   elfcpp::EM_AARCH64,   // machine_code
3607   false,                // has_make_symbol
3608   false,                // has_resolve
3609   false,                // has_code_fill
3610   false,                // is_default_stack_executable
3611   false,                // can_icf_inline_merge_sections
3612   '\0',                 // wrap_char
3613   "/lib/ld.so.1",       // program interpreter
3614   0x400000,             // default_text_segment_address
3615   0x10000,              // abi_pagesize (overridable by -z max-page-size)
3616   0x1000,               // common_pagesize (overridable by -z common-page-size)
3617   false,                // isolate_execinstr
3618   0,                    // rosegment_gap
3619   elfcpp::SHN_UNDEF,    // small_common_shndx
3620   elfcpp::SHN_UNDEF,    // large_common_shndx
3621   0,                    // small_common_section_flags
3622   0,                    // large_common_section_flags
3623   NULL,                 // attributes_section
3624   NULL,                 // attributes_vendor
3625   "_start",             // entry_symbol_name
3626   32,                   // hash_entry_size
3627 };
3628
3629 // Get the GOT section, creating it if necessary.
3630
3631 template<int size, bool big_endian>
3632 Output_data_got_aarch64<size, big_endian>*
3633 Target_aarch64<size, big_endian>::got_section(Symbol_table* symtab,
3634                                               Layout* layout)
3635 {
3636   if (this->got_ == NULL)
3637     {
3638       gold_assert(symtab != NULL && layout != NULL);
3639
3640       // When using -z now, we can treat .got.plt as a relro section.
3641       // Without -z now, it is modified after program startup by lazy
3642       // PLT relocations.
3643       bool is_got_plt_relro = parameters->options().now();
3644       Output_section_order got_order = (is_got_plt_relro
3645                                         ? ORDER_RELRO
3646                                         : ORDER_RELRO_LAST);
3647       Output_section_order got_plt_order = (is_got_plt_relro
3648                                             ? ORDER_RELRO
3649                                             : ORDER_NON_RELRO_FIRST);
3650
3651       // Layout of .got and .got.plt sections.
3652       // .got[0] &_DYNAMIC                          <-_GLOBAL_OFFSET_TABLE_
3653       // ...
3654       // .gotplt[0] reserved for ld.so (&linkmap)   <--DT_PLTGOT
3655       // .gotplt[1] reserved for ld.so (resolver)
3656       // .gotplt[2] reserved
3657
3658       // Generate .got section.
3659       this->got_ = new Output_data_got_aarch64<size, big_endian>(symtab,
3660                                                                  layout);
3661       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3662                                       (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
3663                                       this->got_, got_order, true);
3664       // The first word of GOT is reserved for the address of .dynamic.
3665       // We put 0 here now. The value will be replaced later in
3666       // Output_data_got_aarch64::do_write.
3667       this->got_->add_constant(0);
3668
3669       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3670       // _GLOBAL_OFFSET_TABLE_ value points to the start of the .got section,
3671       // even if there is a .got.plt section.
3672       this->global_offset_table_ =
3673         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
3674                                       Symbol_table::PREDEFINED,
3675                                       this->got_,
3676                                       0, 0, elfcpp::STT_OBJECT,
3677                                       elfcpp::STB_LOCAL,
3678                                       elfcpp::STV_HIDDEN, 0,
3679                                       false, false);
3680
3681       // Generate .got.plt section.
3682       this->got_plt_ = new Output_data_space(size / 8, "** GOT PLT");
3683       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3684                                       (elfcpp::SHF_ALLOC
3685                                        | elfcpp::SHF_WRITE),
3686                                       this->got_plt_, got_plt_order,
3687                                       is_got_plt_relro);
3688
3689       // The first three entries are reserved.
3690       this->got_plt_->set_current_data_size(
3691         AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
3692
3693       // If there are any IRELATIVE relocations, they get GOT entries
3694       // in .got.plt after the jump slot entries.
3695       this->got_irelative_ = new Output_data_space(size / 8,
3696                                                    "** GOT IRELATIVE PLT");
3697       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3698                                       (elfcpp::SHF_ALLOC
3699                                        | elfcpp::SHF_WRITE),
3700                                       this->got_irelative_,
3701                                       got_plt_order,
3702                                       is_got_plt_relro);
3703
3704       // If there are any TLSDESC relocations, they get GOT entries in
3705       // .got.plt after the jump slot and IRELATIVE entries.
3706       this->got_tlsdesc_ = new Output_data_got<size, big_endian>();
3707       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3708                                       (elfcpp::SHF_ALLOC
3709                                        | elfcpp::SHF_WRITE),
3710                                       this->got_tlsdesc_,
3711                                       got_plt_order,
3712                                       is_got_plt_relro);
3713
3714       if (!is_got_plt_relro)
3715         {
3716           // Those bytes can go into the relro segment.
3717           layout->increase_relro(
3718             AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
3719         }
3720
3721     }
3722   return this->got_;
3723 }
3724
3725 // Get the dynamic reloc section, creating it if necessary.
3726
3727 template<int size, bool big_endian>
3728 typename Target_aarch64<size, big_endian>::Reloc_section*
3729 Target_aarch64<size, big_endian>::rela_dyn_section(Layout* layout)
3730 {
3731   if (this->rela_dyn_ == NULL)
3732     {
3733       gold_assert(layout != NULL);
3734       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
3735       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
3736                                       elfcpp::SHF_ALLOC, this->rela_dyn_,
3737                                       ORDER_DYNAMIC_RELOCS, false);
3738     }
3739   return this->rela_dyn_;
3740 }
3741
3742 // Get the section to use for IRELATIVE relocs, creating it if
3743 // necessary.  These go in .rela.dyn, but only after all other dynamic
3744 // relocations.  They need to follow the other dynamic relocations so
3745 // that they can refer to global variables initialized by those
3746 // relocs.
3747
3748 template<int size, bool big_endian>
3749 typename Target_aarch64<size, big_endian>::Reloc_section*
3750 Target_aarch64<size, big_endian>::rela_irelative_section(Layout* layout)
3751 {
3752   if (this->rela_irelative_ == NULL)
3753     {
3754       // Make sure we have already created the dynamic reloc section.
3755       this->rela_dyn_section(layout);
3756       this->rela_irelative_ = new Reloc_section(false);
3757       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
3758                                       elfcpp::SHF_ALLOC, this->rela_irelative_,
3759                                       ORDER_DYNAMIC_RELOCS, false);
3760       gold_assert(this->rela_dyn_->output_section()
3761                   == this->rela_irelative_->output_section());
3762     }
3763   return this->rela_irelative_;
3764 }
3765
3766
3767 // do_make_elf_object to override the same function in the base class.  We need
3768 // to use a target-specific sub-class of Sized_relobj_file<size, big_endian> to
3769 // store backend specific information. Hence we need to have our own ELF object
3770 // creation.
3771
3772 template<int size, bool big_endian>
3773 Object*
3774 Target_aarch64<size, big_endian>::do_make_elf_object(
3775     const std::string& name,
3776     Input_file* input_file,
3777     off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
3778 {
3779   int et = ehdr.get_e_type();
3780   // ET_EXEC files are valid input for --just-symbols/-R,
3781   // and we treat them as relocatable objects.
3782   if (et == elfcpp::ET_EXEC && input_file->just_symbols())
3783     return Sized_target<size, big_endian>::do_make_elf_object(
3784         name, input_file, offset, ehdr);
3785   else if (et == elfcpp::ET_REL)
3786     {
3787       AArch64_relobj<size, big_endian>* obj =
3788         new AArch64_relobj<size, big_endian>(name, input_file, offset, ehdr);
3789       obj->setup();
3790       return obj;
3791     }
3792   else if (et == elfcpp::ET_DYN)
3793     {
3794       // Keep base implementation.
3795       Sized_dynobj<size, big_endian>* obj =
3796           new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
3797       obj->setup();
3798       return obj;
3799     }
3800   else
3801     {
3802       gold_error(_("%s: unsupported ELF file type %d"),
3803                  name.c_str(), et);
3804       return NULL;
3805     }
3806 }
3807
3808
3809 // Scan a relocation for stub generation.
3810
3811 template<int size, bool big_endian>
3812 void
3813 Target_aarch64<size, big_endian>::scan_reloc_for_stub(
3814     const Relocate_info<size, big_endian>* relinfo,
3815     unsigned int r_type,
3816     const Sized_symbol<size>* gsym,
3817     unsigned int r_sym,
3818     const Symbol_value<size>* psymval,
3819     typename elfcpp::Elf_types<size>::Elf_Swxword addend,
3820     Address address)
3821 {
3822   const AArch64_relobj<size, big_endian>* aarch64_relobj =
3823       static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
3824
3825   Symbol_value<size> symval;
3826   if (gsym != NULL)
3827     {
3828       const AArch64_reloc_property* arp = aarch64_reloc_property_table->
3829         get_reloc_property(r_type);
3830       if (gsym->use_plt_offset(arp->reference_flags()))
3831         {
3832           // This uses a PLT, change the symbol value.
3833           symval.set_output_value(this->plt_address_for_global(gsym));
3834           psymval = &symval;
3835         }
3836       else if (gsym->is_undefined())
3837         {
3838           // There is no need to generate a stub symbol if the original symbol
3839           // is undefined.
3840           gold_debug(DEBUG_TARGET,
3841                      "stub: not creating a stub for undefined symbol %s in file %s",
3842                      gsym->name(), aarch64_relobj->name().c_str());
3843           return;
3844         }
3845     }
3846
3847   // Get the symbol value.
3848   typename Symbol_value<size>::Value value = psymval->value(aarch64_relobj, 0);
3849
3850   // Owing to pipelining, the PC relative branches below actually skip
3851   // two instructions when the branch offset is 0.
3852   Address destination = static_cast<Address>(-1);
3853   switch (r_type)
3854     {
3855     case elfcpp::R_AARCH64_CALL26:
3856     case elfcpp::R_AARCH64_JUMP26:
3857       destination = value + addend;
3858       break;
3859     default:
3860       gold_unreachable();
3861     }
3862
3863   int stub_type = The_reloc_stub::
3864       stub_type_for_reloc(r_type, address, destination);
3865   if (stub_type == ST_NONE)
3866     return;
3867
3868   The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
3869   gold_assert(stub_table != NULL);
3870
3871   The_reloc_stub_key key(stub_type, gsym, aarch64_relobj, r_sym, addend);
3872   The_reloc_stub* stub = stub_table->find_reloc_stub(key);
3873   if (stub == NULL)
3874     {
3875       stub = new The_reloc_stub(stub_type);
3876       stub_table->add_reloc_stub(stub, key);
3877     }
3878   stub->set_destination_address(destination);
3879 }  // End of Target_aarch64::scan_reloc_for_stub
3880
3881
3882 // This function scans a relocation section for stub generation.
3883 // The template parameter Relocate must be a class type which provides
3884 // a single function, relocate(), which implements the machine
3885 // specific part of a relocation.
3886
3887 // BIG_ENDIAN is the endianness of the data.  SH_TYPE is the section type:
3888 // SHT_REL or SHT_RELA.
3889
3890 // PRELOCS points to the relocation data.  RELOC_COUNT is the number
3891 // of relocs.  OUTPUT_SECTION is the output section.
3892 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
3893 // mapped to output offsets.
3894
3895 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
3896 // VIEW_SIZE is the size.  These refer to the input section, unless
3897 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
3898 // the output section.
3899
3900 template<int size, bool big_endian>
3901 template<int sh_type>
3902 void inline
3903 Target_aarch64<size, big_endian>::scan_reloc_section_for_stubs(
3904     const Relocate_info<size, big_endian>* relinfo,
3905     const unsigned char* prelocs,
3906     size_t reloc_count,
3907     Output_section* /*output_section*/,
3908     bool /*needs_special_offset_handling*/,
3909     const unsigned char* /*view*/,
3910     Address view_address,
3911     section_size_type)
3912 {
3913   typedef typename Reloc_types<sh_type,size,big_endian>::Reloc Reltype;
3914
3915   const int reloc_size =
3916       Reloc_types<sh_type,size,big_endian>::reloc_size;
3917   AArch64_relobj<size, big_endian>* object =
3918       static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
3919   unsigned int local_count = object->local_symbol_count();
3920
3921   gold::Default_comdat_behavior default_comdat_behavior;
3922   Comdat_behavior comdat_behavior = CB_UNDETERMINED;
3923
3924   for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
3925     {
3926       Reltype reloc(prelocs);
3927       typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
3928       unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
3929       unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
3930       if (r_type != elfcpp::R_AARCH64_CALL26
3931           && r_type != elfcpp::R_AARCH64_JUMP26)
3932         continue;
3933
3934       section_offset_type offset =
3935           convert_to_section_size_type(reloc.get_r_offset());
3936
3937       // Get the addend.
3938       typename elfcpp::Elf_types<size>::Elf_Swxword addend =
3939           reloc.get_r_addend();
3940
3941       const Sized_symbol<size>* sym;
3942       Symbol_value<size> symval;
3943       const Symbol_value<size> *psymval;
3944       bool is_defined_in_discarded_section;
3945       unsigned int shndx;
3946       if (r_sym < local_count)
3947         {
3948           sym = NULL;
3949           psymval = object->local_symbol(r_sym);
3950
3951           // If the local symbol belongs to a section we are discarding,
3952           // and that section is a debug section, try to find the
3953           // corresponding kept section and map this symbol to its
3954           // counterpart in the kept section.  The symbol must not
3955           // correspond to a section we are folding.
3956           bool is_ordinary;
3957           shndx = psymval->input_shndx(&is_ordinary);
3958           is_defined_in_discarded_section =
3959             (is_ordinary
3960              && shndx != elfcpp::SHN_UNDEF
3961              && !object->is_section_included(shndx)
3962              && !relinfo->symtab->is_section_folded(object, shndx));
3963
3964           // We need to compute the would-be final value of this local
3965           // symbol.
3966           if (!is_defined_in_discarded_section)
3967             {
3968               typedef Sized_relobj_file<size, big_endian> ObjType;
3969               if (psymval->is_section_symbol())
3970                 symval.set_is_section_symbol();
3971               typename ObjType::Compute_final_local_value_status status =
3972                 object->compute_final_local_value(r_sym, psymval, &symval,
3973                                                   relinfo->symtab);
3974               if (status == ObjType::CFLV_OK)
3975                 {
3976                   // Currently we cannot handle a branch to a target in
3977                   // a merged section.  If this is the case, issue an error
3978                   // and also free the merge symbol value.
3979                   if (!symval.has_output_value())
3980                     {
3981                       const std::string& section_name =
3982                         object->section_name(shndx);
3983                       object->error(_("cannot handle branch to local %u "
3984                                           "in a merged section %s"),
3985                                         r_sym, section_name.c_str());
3986                     }
3987                   psymval = &symval;
3988                 }
3989               else
3990                 {
3991                   // We cannot determine the final value.
3992                   continue;
3993                 }
3994             }
3995         }
3996       else
3997         {
3998           const Symbol* gsym;
3999           gsym = object->global_symbol(r_sym);
4000           gold_assert(gsym != NULL);
4001           if (gsym->is_forwarder())
4002             gsym = relinfo->symtab->resolve_forwards(gsym);
4003
4004           sym = static_cast<const Sized_symbol<size>*>(gsym);
4005           if (sym->has_symtab_index() && sym->symtab_index() != -1U)
4006             symval.set_output_symtab_index(sym->symtab_index());
4007           else
4008             symval.set_no_output_symtab_entry();
4009
4010           // We need to compute the would-be final value of this global
4011           // symbol.
4012           const Symbol_table* symtab = relinfo->symtab;
4013           const Sized_symbol<size>* sized_symbol =
4014               symtab->get_sized_symbol<size>(gsym);
4015           Symbol_table::Compute_final_value_status status;
4016           typename elfcpp::Elf_types<size>::Elf_Addr value =
4017               symtab->compute_final_value<size>(sized_symbol, &status);
4018
4019           // Skip this if the symbol has not output section.
4020           if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
4021             continue;
4022           symval.set_output_value(value);
4023
4024           if (gsym->type() == elfcpp::STT_TLS)
4025             symval.set_is_tls_symbol();
4026           else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
4027             symval.set_is_ifunc_symbol();
4028           psymval = &symval;
4029
4030           is_defined_in_discarded_section =
4031               (gsym->is_defined_in_discarded_section()
4032                && gsym->is_undefined());
4033           shndx = 0;
4034         }
4035
4036       Symbol_value<size> symval2;
4037       if (is_defined_in_discarded_section)
4038         {
4039           if (comdat_behavior == CB_UNDETERMINED)
4040             {
4041               std::string name = object->section_name(relinfo->data_shndx);
4042               comdat_behavior = default_comdat_behavior.get(name.c_str());
4043             }
4044           if (comdat_behavior == CB_PRETEND)
4045             {
4046               bool found;
4047               typename elfcpp::Elf_types<size>::Elf_Addr value =
4048                 object->map_to_kept_section(shndx, &found);
4049               if (found)
4050                 symval2.set_output_value(value + psymval->input_value());
4051               else
4052                 symval2.set_output_value(0);
4053             }
4054           else
4055             {
4056               if (comdat_behavior == CB_WARNING)
4057                 gold_warning_at_location(relinfo, i, offset,
4058                                          _("relocation refers to discarded "
4059                                            "section"));
4060               symval2.set_output_value(0);
4061             }
4062           symval2.set_no_output_symtab_entry();
4063           psymval = &symval2;
4064         }
4065
4066       this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
4067                                 addend, view_address + offset);
4068     }  // End of iterating relocs in a section
4069 }  // End of Target_aarch64::scan_reloc_section_for_stubs
4070
4071
4072 // Scan an input section for stub generation.
4073
4074 template<int size, bool big_endian>
4075 void
4076 Target_aarch64<size, big_endian>::scan_section_for_stubs(
4077     const Relocate_info<size, big_endian>* relinfo,
4078     unsigned int sh_type,
4079     const unsigned char* prelocs,
4080     size_t reloc_count,
4081     Output_section* output_section,
4082     bool needs_special_offset_handling,
4083     const unsigned char* view,
4084     Address view_address,
4085     section_size_type view_size)
4086 {
4087   gold_assert(sh_type == elfcpp::SHT_RELA);
4088   this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
4089       relinfo,
4090       prelocs,
4091       reloc_count,
4092       output_section,
4093       needs_special_offset_handling,
4094       view,
4095       view_address,
4096       view_size);
4097 }
4098
4099
4100 // Relocate a single reloc stub.
4101
4102 template<int size, bool big_endian>
4103 void Target_aarch64<size, big_endian>::
4104 relocate_reloc_stub(The_reloc_stub* stub,
4105                     const The_relocate_info*,
4106                     Output_section*,
4107                     unsigned char* view,
4108                     Address address,
4109                     section_size_type)
4110 {
4111   typedef AArch64_relocate_functions<size, big_endian> The_reloc_functions;
4112   typedef typename The_reloc_functions::Status The_reloc_functions_status;
4113   typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
4114
4115   Insntype* ip = reinterpret_cast<Insntype*>(view);
4116   int insn_number = stub->insn_num();
4117   const uint32_t* insns = stub->insns();
4118   // Check the insns are really those stub insns.
4119   for (int i = 0; i < insn_number; ++i)
4120     {
4121       Insntype insn = elfcpp::Swap<32,big_endian>::readval(ip + i);
4122       gold_assert(((uint32_t)insn == insns[i]));
4123     }
4124
4125   Address dest = stub->destination_address();
4126
4127   switch(stub->type())
4128     {
4129     case ST_ADRP_BRANCH:
4130       {
4131         // 1st reloc is ADR_PREL_PG_HI21
4132         The_reloc_functions_status status =
4133             The_reloc_functions::adrp(view, dest, address);
4134         // An error should never arise in the above step. If so, please
4135         // check 'aarch64_valid_for_adrp_p'.
4136         gold_assert(status == The_reloc_functions::STATUS_OKAY);
4137
4138         // 2nd reloc is ADD_ABS_LO12_NC
4139         const AArch64_reloc_property* arp =
4140             aarch64_reloc_property_table->get_reloc_property(
4141                 elfcpp::R_AARCH64_ADD_ABS_LO12_NC);
4142         gold_assert(arp != NULL);
4143         status = The_reloc_functions::template
4144             rela_general<32>(view + 4, dest, 0, arp);
4145         // An error should never arise, it is an "_NC" relocation.
4146         gold_assert(status == The_reloc_functions::STATUS_OKAY);
4147       }
4148       break;
4149
4150     case ST_LONG_BRANCH_ABS:
4151       // 1st reloc is R_AARCH64_PREL64, at offset 8
4152       elfcpp::Swap<64,big_endian>::writeval(view + 8, dest);
4153       break;
4154
4155     case ST_LONG_BRANCH_PCREL:
4156       {
4157         // "PC" calculation is the 2nd insn in the stub.
4158         uint64_t offset = dest - (address + 4);
4159         // Offset is placed at offset 4 and 5.
4160         elfcpp::Swap<64,big_endian>::writeval(view + 16, offset);
4161       }
4162       break;
4163
4164     default:
4165       gold_unreachable();
4166     }
4167 }
4168
4169
4170 // A class to handle the PLT data.
4171 // This is an abstract base class that handles most of the linker details
4172 // but does not know the actual contents of PLT entries.  The derived
4173 // classes below fill in those details.
4174
4175 template<int size, bool big_endian>
4176 class Output_data_plt_aarch64 : public Output_section_data
4177 {
4178  public:
4179   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
4180       Reloc_section;
4181   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
4182
4183   Output_data_plt_aarch64(Layout* layout,
4184                           uint64_t addralign,
4185                           Output_data_got_aarch64<size, big_endian>* got,
4186                           Output_data_space* got_plt,
4187                           Output_data_space* got_irelative)
4188     : Output_section_data(addralign), tlsdesc_rel_(NULL), irelative_rel_(NULL),
4189       got_(got), got_plt_(got_plt), got_irelative_(got_irelative),
4190       count_(0), irelative_count_(0), tlsdesc_got_offset_(-1U)
4191   { this->init(layout); }
4192
4193   // Initialize the PLT section.
4194   void
4195   init(Layout* layout);
4196
4197   // Add an entry to the PLT.
4198   void
4199   add_entry(Symbol_table*, Layout*, Symbol* gsym);
4200
4201   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
4202   unsigned int
4203   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
4204                         Sized_relobj_file<size, big_endian>* relobj,
4205                         unsigned int local_sym_index);
4206
4207   // Add the relocation for a PLT entry.
4208   void
4209   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
4210                  unsigned int got_offset);
4211
4212   // Add the reserved TLSDESC_PLT entry to the PLT.
4213   void
4214   reserve_tlsdesc_entry(unsigned int got_offset)
4215   { this->tlsdesc_got_offset_ = got_offset; }
4216
4217   // Return true if a TLSDESC_PLT entry has been reserved.
4218   bool
4219   has_tlsdesc_entry() const
4220   { return this->tlsdesc_got_offset_ != -1U; }
4221
4222   // Return the GOT offset for the reserved TLSDESC_PLT entry.
4223   unsigned int
4224   get_tlsdesc_got_offset() const
4225   { return this->tlsdesc_got_offset_; }
4226
4227   // Return the PLT offset of the reserved TLSDESC_PLT entry.
4228   unsigned int
4229   get_tlsdesc_plt_offset() const
4230   {
4231     return (this->first_plt_entry_offset() +
4232             (this->count_ + this->irelative_count_)
4233             * this->get_plt_entry_size());
4234   }
4235
4236   // Return the .rela.plt section data.
4237   Reloc_section*
4238   rela_plt()
4239   { return this->rel_; }
4240
4241   // Return where the TLSDESC relocations should go.
4242   Reloc_section*
4243   rela_tlsdesc(Layout*);
4244
4245   // Return where the IRELATIVE relocations should go in the PLT
4246   // relocations.
4247   Reloc_section*
4248   rela_irelative(Symbol_table*, Layout*);
4249
4250   // Return whether we created a section for IRELATIVE relocations.
4251   bool
4252   has_irelative_section() const
4253   { return this->irelative_rel_ != NULL; }
4254
4255   // Return the number of PLT entries.
4256   unsigned int
4257   entry_count() const
4258   { return this->count_ + this->irelative_count_; }
4259
4260   // Return the offset of the first non-reserved PLT entry.
4261   unsigned int
4262   first_plt_entry_offset() const
4263   { return this->do_first_plt_entry_offset(); }
4264
4265   // Return the size of a PLT entry.
4266   unsigned int
4267   get_plt_entry_size() const
4268   { return this->do_get_plt_entry_size(); }
4269
4270   // Return the reserved tlsdesc entry size.
4271   unsigned int
4272   get_plt_tlsdesc_entry_size() const
4273   { return this->do_get_plt_tlsdesc_entry_size(); }
4274
4275   // Return the PLT address to use for a global symbol.
4276   uint64_t
4277   address_for_global(const Symbol*);
4278
4279   // Return the PLT address to use for a local symbol.
4280   uint64_t
4281   address_for_local(const Relobj*, unsigned int symndx);
4282
4283  protected:
4284   // Fill in the first PLT entry.
4285   void
4286   fill_first_plt_entry(unsigned char* pov,
4287                        Address got_address,
4288                        Address plt_address)
4289   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
4290
4291   // Fill in a normal PLT entry.
4292   void
4293   fill_plt_entry(unsigned char* pov,
4294                  Address got_address,
4295                  Address plt_address,
4296                  unsigned int got_offset,
4297                  unsigned int plt_offset)
4298   {
4299     this->do_fill_plt_entry(pov, got_address, plt_address,
4300                             got_offset, plt_offset);
4301   }
4302
4303   // Fill in the reserved TLSDESC PLT entry.
4304   void
4305   fill_tlsdesc_entry(unsigned char* pov,
4306                      Address gotplt_address,
4307                      Address plt_address,
4308                      Address got_base,
4309                      unsigned int tlsdesc_got_offset,
4310                      unsigned int plt_offset)
4311   {
4312     this->do_fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
4313                                 tlsdesc_got_offset, plt_offset);
4314   }
4315
4316   virtual unsigned int
4317   do_first_plt_entry_offset() const = 0;
4318
4319   virtual unsigned int
4320   do_get_plt_entry_size() const = 0;
4321
4322   virtual unsigned int
4323   do_get_plt_tlsdesc_entry_size() const = 0;
4324
4325   virtual void
4326   do_fill_first_plt_entry(unsigned char* pov,
4327                           Address got_addr,
4328                           Address plt_addr) = 0;
4329
4330   virtual void
4331   do_fill_plt_entry(unsigned char* pov,
4332                     Address got_address,
4333                     Address plt_address,
4334                     unsigned int got_offset,
4335                     unsigned int plt_offset) = 0;
4336
4337   virtual void
4338   do_fill_tlsdesc_entry(unsigned char* pov,
4339                         Address gotplt_address,
4340                         Address plt_address,
4341                         Address got_base,
4342                         unsigned int tlsdesc_got_offset,
4343                         unsigned int plt_offset) = 0;
4344
4345   void
4346   do_adjust_output_section(Output_section* os);
4347
4348   // Write to a map file.
4349   void
4350   do_print_to_mapfile(Mapfile* mapfile) const
4351   { mapfile->print_output_data(this, _("** PLT")); }
4352
4353  private:
4354   // Set the final size.
4355   void
4356   set_final_data_size();
4357
4358   // Write out the PLT data.
4359   void
4360   do_write(Output_file*);
4361
4362   // The reloc section.
4363   Reloc_section* rel_;
4364
4365   // The TLSDESC relocs, if necessary.  These must follow the regular
4366   // PLT relocs.
4367   Reloc_section* tlsdesc_rel_;
4368
4369   // The IRELATIVE relocs, if necessary.  These must follow the
4370   // regular PLT relocations.
4371   Reloc_section* irelative_rel_;
4372
4373   // The .got section.
4374   Output_data_got_aarch64<size, big_endian>* got_;
4375
4376   // The .got.plt section.
4377   Output_data_space* got_plt_;
4378
4379   // The part of the .got.plt section used for IRELATIVE relocs.
4380   Output_data_space* got_irelative_;
4381
4382   // The number of PLT entries.
4383   unsigned int count_;
4384
4385   // Number of PLT entries with R_AARCH64_IRELATIVE relocs.  These
4386   // follow the regular PLT entries.
4387   unsigned int irelative_count_;
4388
4389   // GOT offset of the reserved TLSDESC_GOT entry for the lazy trampoline.
4390   // Communicated to the loader via DT_TLSDESC_GOT. The magic value -1
4391   // indicates an offset is not allocated.
4392   unsigned int tlsdesc_got_offset_;
4393 };
4394
4395 // Initialize the PLT section.
4396
4397 template<int size, bool big_endian>
4398 void
4399 Output_data_plt_aarch64<size, big_endian>::init(Layout* layout)
4400 {
4401   this->rel_ = new Reloc_section(false);
4402   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4403                                   elfcpp::SHF_ALLOC, this->rel_,
4404                                   ORDER_DYNAMIC_PLT_RELOCS, false);
4405 }
4406
4407 template<int size, bool big_endian>
4408 void
4409 Output_data_plt_aarch64<size, big_endian>::do_adjust_output_section(
4410     Output_section* os)
4411 {
4412   os->set_entsize(this->get_plt_entry_size());
4413 }
4414
4415 // Add an entry to the PLT.
4416
4417 template<int size, bool big_endian>
4418 void
4419 Output_data_plt_aarch64<size, big_endian>::add_entry(Symbol_table* symtab,
4420     Layout* layout, Symbol* gsym)
4421 {
4422   gold_assert(!gsym->has_plt_offset());
4423
4424   unsigned int* pcount;
4425   unsigned int plt_reserved;
4426   Output_section_data_build* got;
4427
4428   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4429       && gsym->can_use_relative_reloc(false))
4430     {
4431       pcount = &this->irelative_count_;
4432       plt_reserved = 0;
4433       got = this->got_irelative_;
4434     }
4435   else
4436     {
4437       pcount = &this->count_;
4438       plt_reserved = this->first_plt_entry_offset();
4439       got = this->got_plt_;
4440     }
4441
4442   gsym->set_plt_offset((*pcount) * this->get_plt_entry_size()
4443                        + plt_reserved);
4444
4445   ++*pcount;
4446
4447   section_offset_type got_offset = got->current_data_size();
4448
4449   // Every PLT entry needs a GOT entry which points back to the PLT
4450   // entry (this will be changed by the dynamic linker, normally
4451   // lazily when the function is called).
4452   got->set_current_data_size(got_offset + size / 8);
4453
4454   // Every PLT entry needs a reloc.
4455   this->add_relocation(symtab, layout, gsym, got_offset);
4456
4457   // Note that we don't need to save the symbol. The contents of the
4458   // PLT are independent of which symbols are used. The symbols only
4459   // appear in the relocations.
4460 }
4461
4462 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
4463 // the PLT offset.
4464
4465 template<int size, bool big_endian>
4466 unsigned int
4467 Output_data_plt_aarch64<size, big_endian>::add_local_ifunc_entry(
4468     Symbol_table* symtab,
4469     Layout* layout,
4470     Sized_relobj_file<size, big_endian>* relobj,
4471     unsigned int local_sym_index)
4472 {
4473   unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
4474   ++this->irelative_count_;
4475
4476   section_offset_type got_offset = this->got_irelative_->current_data_size();
4477
4478   // Every PLT entry needs a GOT entry which points back to the PLT
4479   // entry.
4480   this->got_irelative_->set_current_data_size(got_offset + size / 8);
4481
4482   // Every PLT entry needs a reloc.
4483   Reloc_section* rela = this->rela_irelative(symtab, layout);
4484   rela->add_symbolless_local_addend(relobj, local_sym_index,
4485                                     elfcpp::R_AARCH64_IRELATIVE,
4486                                     this->got_irelative_, got_offset, 0);
4487
4488   return plt_offset;
4489 }
4490
4491 // Add the relocation for a PLT entry.
4492
4493 template<int size, bool big_endian>
4494 void
4495 Output_data_plt_aarch64<size, big_endian>::add_relocation(
4496     Symbol_table* symtab, Layout* layout, Symbol* gsym, unsigned int got_offset)
4497 {
4498   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4499       && gsym->can_use_relative_reloc(false))
4500     {
4501       Reloc_section* rela = this->rela_irelative(symtab, layout);
4502       rela->add_symbolless_global_addend(gsym, elfcpp::R_AARCH64_IRELATIVE,
4503                                          this->got_irelative_, got_offset, 0);
4504     }
4505   else
4506     {
4507       gsym->set_needs_dynsym_entry();
4508       this->rel_->add_global(gsym, elfcpp::R_AARCH64_JUMP_SLOT, this->got_plt_,
4509                              got_offset, 0);
4510     }
4511 }
4512
4513 // Return where the TLSDESC relocations should go, creating it if
4514 // necessary.  These follow the JUMP_SLOT relocations.
4515
4516 template<int size, bool big_endian>
4517 typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
4518 Output_data_plt_aarch64<size, big_endian>::rela_tlsdesc(Layout* layout)
4519 {
4520   if (this->tlsdesc_rel_ == NULL)
4521     {
4522       this->tlsdesc_rel_ = new Reloc_section(false);
4523       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4524                                       elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
4525                                       ORDER_DYNAMIC_PLT_RELOCS, false);
4526       gold_assert(this->tlsdesc_rel_->output_section()
4527                   == this->rel_->output_section());
4528     }
4529   return this->tlsdesc_rel_;
4530 }
4531
4532 // Return where the IRELATIVE relocations should go in the PLT.  These
4533 // follow the JUMP_SLOT and the TLSDESC relocations.
4534
4535 template<int size, bool big_endian>
4536 typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
4537 Output_data_plt_aarch64<size, big_endian>::rela_irelative(Symbol_table* symtab,
4538                                                           Layout* layout)
4539 {
4540   if (this->irelative_rel_ == NULL)
4541     {
4542       // Make sure we have a place for the TLSDESC relocations, in
4543       // case we see any later on.
4544       this->rela_tlsdesc(layout);
4545       this->irelative_rel_ = new Reloc_section(false);
4546       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
4547                                       elfcpp::SHF_ALLOC, this->irelative_rel_,
4548                                       ORDER_DYNAMIC_PLT_RELOCS, false);
4549       gold_assert(this->irelative_rel_->output_section()
4550                   == this->rel_->output_section());
4551
4552       if (parameters->doing_static_link())
4553         {
4554           // A statically linked executable will only have a .rela.plt
4555           // section to hold R_AARCH64_IRELATIVE relocs for
4556           // STT_GNU_IFUNC symbols.  The library will use these
4557           // symbols to locate the IRELATIVE relocs at program startup
4558           // time.
4559           symtab->define_in_output_data("__rela_iplt_start", NULL,
4560                                         Symbol_table::PREDEFINED,
4561                                         this->irelative_rel_, 0, 0,
4562                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
4563                                         elfcpp::STV_HIDDEN, 0, false, true);
4564           symtab->define_in_output_data("__rela_iplt_end", NULL,
4565                                         Symbol_table::PREDEFINED,
4566                                         this->irelative_rel_, 0, 0,
4567                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
4568                                         elfcpp::STV_HIDDEN, 0, true, true);
4569         }
4570     }
4571   return this->irelative_rel_;
4572 }
4573
4574 // Return the PLT address to use for a global symbol.
4575
4576 template<int size, bool big_endian>
4577 uint64_t
4578 Output_data_plt_aarch64<size, big_endian>::address_for_global(
4579   const Symbol* gsym)
4580 {
4581   uint64_t offset = 0;
4582   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4583       && gsym->can_use_relative_reloc(false))
4584     offset = (this->first_plt_entry_offset() +
4585               this->count_ * this->get_plt_entry_size());
4586   return this->address() + offset + gsym->plt_offset();
4587 }
4588
4589 // Return the PLT address to use for a local symbol.  These are always
4590 // IRELATIVE relocs.
4591
4592 template<int size, bool big_endian>
4593 uint64_t
4594 Output_data_plt_aarch64<size, big_endian>::address_for_local(
4595     const Relobj* object,
4596     unsigned int r_sym)
4597 {
4598   return (this->address()
4599           + this->first_plt_entry_offset()
4600           + this->count_ * this->get_plt_entry_size()
4601           + object->local_plt_offset(r_sym));
4602 }
4603
4604 // Set the final size.
4605
4606 template<int size, bool big_endian>
4607 void
4608 Output_data_plt_aarch64<size, big_endian>::set_final_data_size()
4609 {
4610   unsigned int count = this->count_ + this->irelative_count_;
4611   unsigned int extra_size = 0;
4612   if (this->has_tlsdesc_entry())
4613     extra_size += this->get_plt_tlsdesc_entry_size();
4614   this->set_data_size(this->first_plt_entry_offset()
4615                       + count * this->get_plt_entry_size()
4616                       + extra_size);
4617 }
4618
4619 template<int size, bool big_endian>
4620 class Output_data_plt_aarch64_standard :
4621   public Output_data_plt_aarch64<size, big_endian>
4622 {
4623  public:
4624   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
4625   Output_data_plt_aarch64_standard(
4626       Layout* layout,
4627       Output_data_got_aarch64<size, big_endian>* got,
4628       Output_data_space* got_plt,
4629       Output_data_space* got_irelative)
4630     : Output_data_plt_aarch64<size, big_endian>(layout,
4631                                                 size == 32 ? 4 : 8,
4632                                                 got, got_plt,
4633                                                 got_irelative)
4634   { }
4635
4636  protected:
4637   // Return the offset of the first non-reserved PLT entry.
4638   virtual unsigned int
4639   do_first_plt_entry_offset() const
4640   { return this->first_plt_entry_size; }
4641
4642   // Return the size of a PLT entry
4643   virtual unsigned int
4644   do_get_plt_entry_size() const
4645   { return this->plt_entry_size; }
4646
4647   // Return the size of a tlsdesc entry
4648   virtual unsigned int
4649   do_get_plt_tlsdesc_entry_size() const
4650   { return this->plt_tlsdesc_entry_size; }
4651
4652   virtual void
4653   do_fill_first_plt_entry(unsigned char* pov,
4654                           Address got_address,
4655                           Address plt_address);
4656
4657   virtual void
4658   do_fill_plt_entry(unsigned char* pov,
4659                     Address got_address,
4660                     Address plt_address,
4661                     unsigned int got_offset,
4662                     unsigned int plt_offset);
4663
4664   virtual void
4665   do_fill_tlsdesc_entry(unsigned char* pov,
4666                         Address gotplt_address,
4667                         Address plt_address,
4668                         Address got_base,
4669                         unsigned int tlsdesc_got_offset,
4670                         unsigned int plt_offset);
4671
4672  private:
4673   // The size of the first plt entry size.
4674   static const int first_plt_entry_size = 32;
4675   // The size of the plt entry size.
4676   static const int plt_entry_size = 16;
4677   // The size of the plt tlsdesc entry size.
4678   static const int plt_tlsdesc_entry_size = 32;
4679   // Template for the first PLT entry.
4680   static const uint32_t first_plt_entry[first_plt_entry_size / 4];
4681   // Template for subsequent PLT entries.
4682   static const uint32_t plt_entry[plt_entry_size / 4];
4683   // The reserved TLSDESC entry in the PLT for an executable.
4684   static const uint32_t tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4];
4685 };
4686
4687 // The first entry in the PLT for an executable.
4688
4689 template<>
4690 const uint32_t
4691 Output_data_plt_aarch64_standard<32, false>::
4692     first_plt_entry[first_plt_entry_size / 4] =
4693 {
4694   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4695   0x90000010,   /* adrp x16, PLT_GOT+0x8  */
4696   0xb9400A11,   /* ldr w17, [x16, #PLT_GOT+0x8]  */
4697   0x11002210,   /* add w16, w16,#PLT_GOT+0x8   */
4698   0xd61f0220,   /* br x17  */
4699   0xd503201f,   /* nop */
4700   0xd503201f,   /* nop */
4701   0xd503201f,   /* nop */
4702 };
4703
4704
4705 template<>
4706 const uint32_t
4707 Output_data_plt_aarch64_standard<32, true>::
4708     first_plt_entry[first_plt_entry_size / 4] =
4709 {
4710   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4711   0x90000010,   /* adrp x16, PLT_GOT+0x8  */
4712   0xb9400A11,   /* ldr w17, [x16, #PLT_GOT+0x8]  */
4713   0x11002210,   /* add w16, w16,#PLT_GOT+0x8   */
4714   0xd61f0220,   /* br x17  */
4715   0xd503201f,   /* nop */
4716   0xd503201f,   /* nop */
4717   0xd503201f,   /* nop */
4718 };
4719
4720
4721 template<>
4722 const uint32_t
4723 Output_data_plt_aarch64_standard<64, false>::
4724     first_plt_entry[first_plt_entry_size / 4] =
4725 {
4726   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4727   0x90000010,   /* adrp x16, PLT_GOT+16  */
4728   0xf9400A11,   /* ldr x17, [x16, #PLT_GOT+0x10]  */
4729   0x91004210,   /* add x16, x16,#PLT_GOT+0x10   */
4730   0xd61f0220,   /* br x17  */
4731   0xd503201f,   /* nop */
4732   0xd503201f,   /* nop */
4733   0xd503201f,   /* nop */
4734 };
4735
4736
4737 template<>
4738 const uint32_t
4739 Output_data_plt_aarch64_standard<64, true>::
4740     first_plt_entry[first_plt_entry_size / 4] =
4741 {
4742   0xa9bf7bf0,   /* stp x16, x30, [sp, #-16]!  */
4743   0x90000010,   /* adrp x16, PLT_GOT+16  */
4744   0xf9400A11,   /* ldr x17, [x16, #PLT_GOT+0x10]  */
4745   0x91004210,   /* add x16, x16,#PLT_GOT+0x10   */
4746   0xd61f0220,   /* br x17  */
4747   0xd503201f,   /* nop */
4748   0xd503201f,   /* nop */
4749   0xd503201f,   /* nop */
4750 };
4751
4752
4753 template<>
4754 const uint32_t
4755 Output_data_plt_aarch64_standard<32, false>::
4756     plt_entry[plt_entry_size / 4] =
4757 {
4758   0x90000010,   /* adrp x16, PLTGOT + n * 4  */
4759   0xb9400211,   /* ldr w17, [w16, PLTGOT + n * 4] */
4760   0x11000210,   /* add w16, w16, :lo12:PLTGOT + n * 4  */
4761   0xd61f0220,   /* br x17.  */
4762 };
4763
4764
4765 template<>
4766 const uint32_t
4767 Output_data_plt_aarch64_standard<32, true>::
4768     plt_entry[plt_entry_size / 4] =
4769 {
4770   0x90000010,   /* adrp x16, PLTGOT + n * 4  */
4771   0xb9400211,   /* ldr w17, [w16, PLTGOT + n * 4] */
4772   0x11000210,   /* add w16, w16, :lo12:PLTGOT + n * 4  */
4773   0xd61f0220,   /* br x17.  */
4774 };
4775
4776
4777 template<>
4778 const uint32_t
4779 Output_data_plt_aarch64_standard<64, false>::
4780     plt_entry[plt_entry_size / 4] =
4781 {
4782   0x90000010,   /* adrp x16, PLTGOT + n * 8  */
4783   0xf9400211,   /* ldr x17, [x16, PLTGOT + n * 8] */
4784   0x91000210,   /* add x16, x16, :lo12:PLTGOT + n * 8  */
4785   0xd61f0220,   /* br x17.  */
4786 };
4787
4788
4789 template<>
4790 const uint32_t
4791 Output_data_plt_aarch64_standard<64, true>::
4792     plt_entry[plt_entry_size / 4] =
4793 {
4794   0x90000010,   /* adrp x16, PLTGOT + n * 8  */
4795   0xf9400211,   /* ldr x17, [x16, PLTGOT + n * 8] */
4796   0x91000210,   /* add x16, x16, :lo12:PLTGOT + n * 8  */
4797   0xd61f0220,   /* br x17.  */
4798 };
4799
4800
4801 template<int size, bool big_endian>
4802 void
4803 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_first_plt_entry(
4804     unsigned char* pov,
4805     Address got_address,
4806     Address plt_address)
4807 {
4808   // PLT0 of the small PLT looks like this in ELF64 -
4809   // stp x16, x30, [sp, #-16]!          Save the reloc and lr on stack.
4810   // adrp x16, PLT_GOT + 16             Get the page base of the GOTPLT
4811   // ldr  x17, [x16, #:lo12:PLT_GOT+16] Load the address of the
4812   //                                    symbol resolver
4813   // add  x16, x16, #:lo12:PLT_GOT+16   Load the lo12 bits of the
4814   //                                    GOTPLT entry for this.
4815   // br   x17
4816   // PLT0 will be slightly different in ELF32 due to different got entry
4817   // size.
4818   memcpy(pov, this->first_plt_entry, this->first_plt_entry_size);
4819   Address gotplt_2nd_ent = got_address + (size / 8) * 2;
4820
4821   // Fill in the top 21 bits for this: ADRP x16, PLT_GOT + 8 * 2.
4822   // ADRP:  (PG(S+A)-PG(P)) >> 12) & 0x1fffff.
4823   // FIXME: This only works for 64bit
4824   AArch64_relocate_functions<size, big_endian>::adrp(pov + 4,
4825       gotplt_2nd_ent, plt_address + 4);
4826
4827   // Fill in R_AARCH64_LDST8_LO12
4828   elfcpp::Swap<32, big_endian>::writeval(
4829       pov + 8,
4830       ((this->first_plt_entry[2] & 0xffc003ff)
4831        | ((gotplt_2nd_ent & 0xff8) << 7)));
4832
4833   // Fill in R_AARCH64_ADD_ABS_LO12
4834   elfcpp::Swap<32, big_endian>::writeval(
4835       pov + 12,
4836       ((this->first_plt_entry[3] & 0xffc003ff)
4837        | ((gotplt_2nd_ent & 0xfff) << 10)));
4838 }
4839
4840
4841 // Subsequent entries in the PLT for an executable.
4842 // FIXME: This only works for 64bit
4843
4844 template<int size, bool big_endian>
4845 void
4846 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_plt_entry(
4847     unsigned char* pov,
4848     Address got_address,
4849     Address plt_address,
4850     unsigned int got_offset,
4851     unsigned int plt_offset)
4852 {
4853   memcpy(pov, this->plt_entry, this->plt_entry_size);
4854
4855   Address gotplt_entry_address = got_address + got_offset;
4856   Address plt_entry_address = plt_address + plt_offset;
4857
4858   // Fill in R_AARCH64_PCREL_ADR_HI21
4859   AArch64_relocate_functions<size, big_endian>::adrp(
4860       pov,
4861       gotplt_entry_address,
4862       plt_entry_address);
4863
4864   // Fill in R_AARCH64_LDST64_ABS_LO12
4865   elfcpp::Swap<32, big_endian>::writeval(
4866       pov + 4,
4867       ((this->plt_entry[1] & 0xffc003ff)
4868        | ((gotplt_entry_address & 0xff8) << 7)));
4869
4870   // Fill in R_AARCH64_ADD_ABS_LO12
4871   elfcpp::Swap<32, big_endian>::writeval(
4872       pov + 8,
4873       ((this->plt_entry[2] & 0xffc003ff)
4874        | ((gotplt_entry_address & 0xfff) <<10)));
4875
4876 }
4877
4878
4879 template<>
4880 const uint32_t
4881 Output_data_plt_aarch64_standard<32, false>::
4882     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4883 {
4884   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4885   0x90000002,   /* adrp x2, 0 */
4886   0x90000003,   /* adrp x3, 0 */
4887   0xb9400042,   /* ldr w2, [w2, #0] */
4888   0x11000063,   /* add w3, w3, 0 */
4889   0xd61f0040,   /* br x2 */
4890   0xd503201f,   /* nop */
4891   0xd503201f,   /* nop */
4892 };
4893
4894 template<>
4895 const uint32_t
4896 Output_data_plt_aarch64_standard<32, true>::
4897     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4898 {
4899   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4900   0x90000002,   /* adrp x2, 0 */
4901   0x90000003,   /* adrp x3, 0 */
4902   0xb9400042,   /* ldr w2, [w2, #0] */
4903   0x11000063,   /* add w3, w3, 0 */
4904   0xd61f0040,   /* br x2 */
4905   0xd503201f,   /* nop */
4906   0xd503201f,   /* nop */
4907 };
4908
4909 template<>
4910 const uint32_t
4911 Output_data_plt_aarch64_standard<64, false>::
4912     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4913 {
4914   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4915   0x90000002,   /* adrp x2, 0 */
4916   0x90000003,   /* adrp x3, 0 */
4917   0xf9400042,   /* ldr x2, [x2, #0] */
4918   0x91000063,   /* add x3, x3, 0 */
4919   0xd61f0040,   /* br x2 */
4920   0xd503201f,   /* nop */
4921   0xd503201f,   /* nop */
4922 };
4923
4924 template<>
4925 const uint32_t
4926 Output_data_plt_aarch64_standard<64, true>::
4927     tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
4928 {
4929   0xa9bf0fe2,   /* stp x2, x3, [sp, #-16]!  */
4930   0x90000002,   /* adrp x2, 0 */
4931   0x90000003,   /* adrp x3, 0 */
4932   0xf9400042,   /* ldr x2, [x2, #0] */
4933   0x91000063,   /* add x3, x3, 0 */
4934   0xd61f0040,   /* br x2 */
4935   0xd503201f,   /* nop */
4936   0xd503201f,   /* nop */
4937 };
4938
4939 template<int size, bool big_endian>
4940 void
4941 Output_data_plt_aarch64_standard<size, big_endian>::do_fill_tlsdesc_entry(
4942     unsigned char* pov,
4943     Address gotplt_address,
4944     Address plt_address,
4945     Address got_base,
4946     unsigned int tlsdesc_got_offset,
4947     unsigned int plt_offset)
4948 {
4949   memcpy(pov, tlsdesc_plt_entry, plt_tlsdesc_entry_size);
4950
4951   // move DT_TLSDESC_GOT address into x2
4952   // move .got.plt address into x3
4953   Address tlsdesc_got_entry = got_base + tlsdesc_got_offset;
4954   Address plt_entry_address = plt_address + plt_offset;
4955
4956   // R_AARCH64_ADR_PREL_PG_HI21
4957   AArch64_relocate_functions<size, big_endian>::adrp(
4958       pov + 4,
4959       tlsdesc_got_entry,
4960       plt_entry_address + 4);
4961
4962   // R_AARCH64_ADR_PREL_PG_HI21
4963   AArch64_relocate_functions<size, big_endian>::adrp(
4964       pov + 8,
4965       gotplt_address,
4966       plt_entry_address + 8);
4967
4968   // R_AARCH64_LDST64_ABS_LO12
4969   elfcpp::Swap<32, big_endian>::writeval(
4970       pov + 12,
4971       ((this->tlsdesc_plt_entry[3] & 0xffc003ff)
4972        | ((tlsdesc_got_entry & 0xff8) << 7)));
4973
4974   // R_AARCH64_ADD_ABS_LO12
4975   elfcpp::Swap<32, big_endian>::writeval(
4976       pov + 16,
4977       ((this->tlsdesc_plt_entry[4] & 0xffc003ff)
4978        | ((gotplt_address & 0xfff) << 10)));
4979 }
4980
4981 // Write out the PLT.  This uses the hand-coded instructions above,
4982 // and adjusts them as needed.  This is specified by the AMD64 ABI.
4983
4984 template<int size, bool big_endian>
4985 void
4986 Output_data_plt_aarch64<size, big_endian>::do_write(Output_file* of)
4987 {
4988   const off_t offset = this->offset();
4989   const section_size_type oview_size =
4990     convert_to_section_size_type(this->data_size());
4991   unsigned char* const oview = of->get_output_view(offset, oview_size);
4992
4993   const off_t got_file_offset = this->got_plt_->offset();
4994   gold_assert(got_file_offset + this->got_plt_->data_size()
4995               == this->got_irelative_->offset());
4996
4997   const section_size_type got_size =
4998       convert_to_section_size_type(this->got_plt_->data_size()
4999                                    + this->got_irelative_->data_size());
5000   unsigned char* const got_view = of->get_output_view(got_file_offset,
5001                                                       got_size);
5002
5003   unsigned char* pov = oview;
5004
5005   // The base address of the .plt section.
5006   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
5007   // The base address of the PLT portion of the .got section.
5008   typename elfcpp::Elf_types<size>::Elf_Addr gotplt_address
5009       = this->got_plt_->address();
5010
5011   this->fill_first_plt_entry(pov, gotplt_address, plt_address);
5012   pov += this->first_plt_entry_offset();
5013
5014   // The first three entries in .got.plt are reserved.
5015   unsigned char* got_pov = got_view;
5016   memset(got_pov, 0, size / 8 * AARCH64_GOTPLT_RESERVE_COUNT);
5017   got_pov += (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
5018
5019   unsigned int plt_offset = this->first_plt_entry_offset();
5020   unsigned int got_offset = (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
5021   const unsigned int count = this->count_ + this->irelative_count_;
5022   for (unsigned int plt_index = 0;
5023        plt_index < count;
5024        ++plt_index,
5025          pov += this->get_plt_entry_size(),
5026          got_pov += size / 8,
5027          plt_offset += this->get_plt_entry_size(),
5028          got_offset += size / 8)
5029     {
5030       // Set and adjust the PLT entry itself.
5031       this->fill_plt_entry(pov, gotplt_address, plt_address,
5032                            got_offset, plt_offset);
5033
5034       // Set the entry in the GOT, which points to plt0.
5035       elfcpp::Swap<size, big_endian>::writeval(got_pov, plt_address);
5036     }
5037
5038   if (this->has_tlsdesc_entry())
5039     {
5040       // Set and adjust the reserved TLSDESC PLT entry.
5041       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
5042       // The base address of the .base section.
5043       typename elfcpp::Elf_types<size>::Elf_Addr got_base =
5044           this->got_->address();
5045       this->fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
5046                                tlsdesc_got_offset, plt_offset);
5047       pov += this->get_plt_tlsdesc_entry_size();
5048     }
5049
5050   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
5051   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
5052
5053   of->write_output_view(offset, oview_size, oview);
5054   of->write_output_view(got_file_offset, got_size, got_view);
5055 }
5056
5057 // Telling how to update the immediate field of an instruction.
5058 struct AArch64_howto
5059 {
5060   // The immediate field mask.
5061   elfcpp::Elf_Xword dst_mask;
5062
5063   // The offset to apply relocation immediate
5064   int doffset;
5065
5066   // The second part offset, if the immediate field has two parts.
5067   // -1 if the immediate field has only one part.
5068   int doffset2;
5069 };
5070
5071 static const AArch64_howto aarch64_howto[AArch64_reloc_property::INST_NUM] =
5072 {
5073   {0, -1, -1},          // DATA
5074   {0x1fffe0, 5, -1},    // MOVW  [20:5]-imm16
5075   {0xffffe0, 5, -1},    // LD    [23:5]-imm19
5076   {0x60ffffe0, 29, 5},  // ADR   [30:29]-immlo  [23:5]-immhi
5077   {0x60ffffe0, 29, 5},  // ADRP  [30:29]-immlo  [23:5]-immhi
5078   {0x3ffc00, 10, -1},   // ADD   [21:10]-imm12
5079   {0x3ffc00, 10, -1},   // LDST  [21:10]-imm12
5080   {0x7ffe0, 5, -1},     // TBZNZ [18:5]-imm14
5081   {0xffffe0, 5, -1},    // CONDB [23:5]-imm19
5082   {0x3ffffff, 0, -1},   // B     [25:0]-imm26
5083   {0x3ffffff, 0, -1},   // CALL  [25:0]-imm26
5084 };
5085
5086 // AArch64 relocate function class
5087
5088 template<int size, bool big_endian>
5089 class AArch64_relocate_functions
5090 {
5091  public:
5092   typedef enum
5093   {
5094     STATUS_OKAY,        // No error during relocation.
5095     STATUS_OVERFLOW,    // Relocation overflow.
5096     STATUS_BAD_RELOC,   // Relocation cannot be applied.
5097   } Status;
5098
5099   typedef AArch64_relocate_functions<size, big_endian> This;
5100   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
5101   typedef Relocate_info<size, big_endian> The_relocate_info;
5102   typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
5103   typedef Reloc_stub<size, big_endian> The_reloc_stub;
5104   typedef Stub_table<size, big_endian> The_stub_table;
5105   typedef elfcpp::Rela<size, big_endian> The_rela;
5106   typedef typename elfcpp::Swap<size, big_endian>::Valtype AArch64_valtype;
5107
5108   // Return the page address of the address.
5109   // Page(address) = address & ~0xFFF
5110
5111   static inline AArch64_valtype
5112   Page(Address address)
5113   {
5114     return (address & (~static_cast<Address>(0xFFF)));
5115   }
5116
5117  private:
5118   // Update instruction (pointed by view) with selected bits (immed).
5119   // val = (val & ~dst_mask) | (immed << doffset)
5120
5121   template<int valsize>
5122   static inline void
5123   update_view(unsigned char* view,
5124               AArch64_valtype immed,
5125               elfcpp::Elf_Xword doffset,
5126               elfcpp::Elf_Xword dst_mask)
5127   {
5128     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5129     Valtype* wv = reinterpret_cast<Valtype*>(view);
5130     Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
5131
5132     // Clear immediate fields.
5133     val &= ~dst_mask;
5134     elfcpp::Swap<valsize, big_endian>::writeval(wv,
5135       static_cast<Valtype>(val | (immed << doffset)));
5136   }
5137
5138   // Update two parts of an instruction (pointed by view) with selected
5139   // bits (immed1 and immed2).
5140   // val = (val & ~dst_mask) | (immed1 << doffset1) | (immed2 << doffset2)
5141
5142   template<int valsize>
5143   static inline void
5144   update_view_two_parts(
5145     unsigned char* view,
5146     AArch64_valtype immed1,
5147     AArch64_valtype immed2,
5148     elfcpp::Elf_Xword doffset1,
5149     elfcpp::Elf_Xword doffset2,
5150     elfcpp::Elf_Xword dst_mask)
5151   {
5152     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5153     Valtype* wv = reinterpret_cast<Valtype*>(view);
5154     Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
5155     val &= ~dst_mask;
5156     elfcpp::Swap<valsize, big_endian>::writeval(wv,
5157       static_cast<Valtype>(val | (immed1 << doffset1) |
5158                            (immed2 << doffset2)));
5159   }
5160
5161   // Update adr or adrp instruction with immed.
5162   // In adr and adrp: [30:29] immlo   [23:5] immhi
5163
5164   static inline void
5165   update_adr(unsigned char* view, AArch64_valtype immed)
5166   {
5167     elfcpp::Elf_Xword dst_mask = (0x3 << 29) | (0x7ffff << 5);
5168     This::template update_view_two_parts<32>(
5169       view,
5170       immed & 0x3,
5171       (immed & 0x1ffffc) >> 2,
5172       29,
5173       5,
5174       dst_mask);
5175   }
5176
5177   // Update movz/movn instruction with bits immed.
5178   // Set instruction to movz if is_movz is true, otherwise set instruction
5179   // to movn.
5180
5181   static inline void
5182   update_movnz(unsigned char* view,
5183                AArch64_valtype immed,
5184                bool is_movz)
5185   {
5186     typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5187     Valtype* wv = reinterpret_cast<Valtype*>(view);
5188     Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
5189
5190     const elfcpp::Elf_Xword doffset =
5191         aarch64_howto[AArch64_reloc_property::INST_MOVW].doffset;
5192     const elfcpp::Elf_Xword dst_mask =
5193         aarch64_howto[AArch64_reloc_property::INST_MOVW].dst_mask;
5194
5195     // Clear immediate fields and opc code.
5196     val &= ~(dst_mask | (0x3 << 29));
5197
5198     // Set instruction to movz or movn.
5199     // movz: [30:29] is 10   movn: [30:29] is 00
5200     if (is_movz)
5201       val |= (0x2 << 29);
5202
5203     elfcpp::Swap<32, big_endian>::writeval(wv,
5204       static_cast<Valtype>(val | (immed << doffset)));
5205   }
5206
5207  public:
5208
5209   // Update selected bits in text.
5210
5211   template<int valsize>
5212   static inline typename This::Status
5213   reloc_common(unsigned char* view, Address x,
5214                 const AArch64_reloc_property* reloc_property)
5215   {
5216     // Select bits from X.
5217     Address immed = reloc_property->select_x_value(x);
5218
5219     // Update view.
5220     const AArch64_reloc_property::Reloc_inst inst =
5221       reloc_property->reloc_inst();
5222     // If it is a data relocation or instruction has 2 parts of immediate
5223     // fields, you should not call pcrela_general.
5224     gold_assert(aarch64_howto[inst].doffset2 == -1 &&
5225                 aarch64_howto[inst].doffset != -1);
5226     This::template update_view<valsize>(view, immed,
5227                                         aarch64_howto[inst].doffset,
5228                                         aarch64_howto[inst].dst_mask);
5229
5230     // Do check overflow or alignment if needed.
5231     return (reloc_property->checkup_x_value(x)
5232             ? This::STATUS_OKAY
5233             : This::STATUS_OVERFLOW);
5234   }
5235
5236   // Construct a B insn. Note, although we group it here with other relocation
5237   // operation, there is actually no 'relocation' involved here.
5238   static inline void
5239   construct_b(unsigned char* view, unsigned int branch_offset)
5240   {
5241     update_view_two_parts<32>(view, 0x05, (branch_offset >> 2),
5242                               26, 0, 0xffffffff);
5243   }
5244
5245   // Do a simple rela relocation at unaligned addresses.
5246
5247   template<int valsize>
5248   static inline typename This::Status
5249   rela_ua(unsigned char* view,
5250           const Sized_relobj_file<size, big_endian>* object,
5251           const Symbol_value<size>* psymval,
5252           AArch64_valtype addend,
5253           const AArch64_reloc_property* reloc_property)
5254   {
5255     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
5256       Valtype;
5257     typename elfcpp::Elf_types<size>::Elf_Addr x =
5258         psymval->value(object, addend);
5259     elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
5260       static_cast<Valtype>(x));
5261     return (reloc_property->checkup_x_value(x)
5262             ? This::STATUS_OKAY
5263             : This::STATUS_OVERFLOW);
5264   }
5265
5266   // Do a simple pc-relative relocation at unaligned addresses.
5267
5268   template<int valsize>
5269   static inline typename This::Status
5270   pcrela_ua(unsigned char* view,
5271             const Sized_relobj_file<size, big_endian>* object,
5272             const Symbol_value<size>* psymval,
5273             AArch64_valtype addend,
5274             Address address,
5275             const AArch64_reloc_property* reloc_property)
5276   {
5277     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
5278       Valtype;
5279     Address x = psymval->value(object, addend) - address;
5280     elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
5281       static_cast<Valtype>(x));
5282     return (reloc_property->checkup_x_value(x)
5283             ? This::STATUS_OKAY
5284             : This::STATUS_OVERFLOW);
5285   }
5286
5287   // Do a simple rela relocation at aligned addresses.
5288
5289   template<int valsize>
5290   static inline typename This::Status
5291   rela(
5292     unsigned char* view,
5293     const Sized_relobj_file<size, big_endian>* object,
5294     const Symbol_value<size>* psymval,
5295     AArch64_valtype addend,
5296     const AArch64_reloc_property* reloc_property)
5297   {
5298     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
5299     Valtype* wv = reinterpret_cast<Valtype*>(view);
5300     Address x = psymval->value(object, addend);
5301     elfcpp::Swap<valsize, big_endian>::writeval(wv,static_cast<Valtype>(x));
5302     return (reloc_property->checkup_x_value(x)
5303             ? This::STATUS_OKAY
5304             : This::STATUS_OVERFLOW);
5305   }
5306
5307   // Do relocate. Update selected bits in text.
5308   // new_val = (val & ~dst_mask) | (immed << doffset)
5309
5310   template<int valsize>
5311   static inline typename This::Status
5312   rela_general(unsigned char* view,
5313                const Sized_relobj_file<size, big_endian>* object,
5314                const Symbol_value<size>* psymval,
5315                AArch64_valtype addend,
5316                const AArch64_reloc_property* reloc_property)
5317   {
5318     // Calculate relocation.
5319     Address x = psymval->value(object, addend);
5320     return This::template reloc_common<valsize>(view, x, reloc_property);
5321   }
5322
5323   // Do relocate. Update selected bits in text.
5324   // new val = (val & ~dst_mask) | (immed << doffset)
5325
5326   template<int valsize>
5327   static inline typename This::Status
5328   rela_general(
5329     unsigned char* view,
5330     AArch64_valtype s,
5331     AArch64_valtype addend,
5332     const AArch64_reloc_property* reloc_property)
5333   {
5334     // Calculate relocation.
5335     Address x = s + addend;
5336     return This::template reloc_common<valsize>(view, x, reloc_property);
5337   }
5338
5339   // Do address relative relocate. Update selected bits in text.
5340   // new val = (val & ~dst_mask) | (immed << doffset)
5341
5342   template<int valsize>
5343   static inline typename This::Status
5344   pcrela_general(
5345     unsigned char* view,
5346     const Sized_relobj_file<size, big_endian>* object,
5347     const Symbol_value<size>* psymval,
5348     AArch64_valtype addend,
5349     Address address,
5350     const AArch64_reloc_property* reloc_property)
5351   {
5352     // Calculate relocation.
5353     Address x = psymval->value(object, addend) - address;
5354     return This::template reloc_common<valsize>(view, x, reloc_property);
5355   }
5356
5357
5358   // Calculate (S + A) - address, update adr instruction.
5359
5360   static inline typename This::Status
5361   adr(unsigned char* view,
5362       const Sized_relobj_file<size, big_endian>* object,
5363       const Symbol_value<size>* psymval,
5364       Address addend,
5365       Address address,
5366       const AArch64_reloc_property* /* reloc_property */)
5367   {
5368     AArch64_valtype x = psymval->value(object, addend) - address;
5369     // Pick bits [20:0] of X.
5370     AArch64_valtype immed = x & 0x1fffff;
5371     update_adr(view, immed);
5372     // Check -2^20 <= X < 2^20
5373     return (size == 64 && Bits<21>::has_overflow((x))
5374             ? This::STATUS_OVERFLOW
5375             : This::STATUS_OKAY);
5376   }
5377
5378   // Calculate PG(S+A) - PG(address), update adrp instruction.
5379   // R_AARCH64_ADR_PREL_PG_HI21
5380
5381   static inline typename This::Status
5382   adrp(
5383     unsigned char* view,
5384     Address sa,
5385     Address address)
5386   {
5387     AArch64_valtype x = This::Page(sa) - This::Page(address);
5388     // Pick [32:12] of X.
5389     AArch64_valtype immed = (x >> 12) & 0x1fffff;
5390     update_adr(view, immed);
5391     // Check -2^32 <= X < 2^32
5392     return (size == 64 && Bits<33>::has_overflow((x))
5393             ? This::STATUS_OVERFLOW
5394             : This::STATUS_OKAY);
5395   }
5396
5397   // Calculate PG(S+A) - PG(address), update adrp instruction.
5398   // R_AARCH64_ADR_PREL_PG_HI21
5399
5400   static inline typename This::Status
5401   adrp(unsigned char* view,
5402        const Sized_relobj_file<size, big_endian>* object,
5403        const Symbol_value<size>* psymval,
5404        Address addend,
5405        Address address,
5406        const AArch64_reloc_property* reloc_property)
5407   {
5408     Address sa = psymval->value(object, addend);
5409     AArch64_valtype x = This::Page(sa) - This::Page(address);
5410     // Pick [32:12] of X.
5411     AArch64_valtype immed = (x >> 12) & 0x1fffff;
5412     update_adr(view, immed);
5413     return (reloc_property->checkup_x_value(x)
5414             ? This::STATUS_OKAY
5415             : This::STATUS_OVERFLOW);
5416   }
5417
5418   // Update mov[n/z] instruction. Check overflow if needed.
5419   // If X >=0, set the instruction to movz and its immediate value to the
5420   // selected bits S.
5421   // If X < 0, set the instruction to movn and its immediate value to
5422   // NOT (selected bits of).
5423
5424   static inline typename This::Status
5425   movnz(unsigned char* view,
5426         AArch64_valtype x,
5427         const AArch64_reloc_property* reloc_property)
5428   {
5429     // Select bits from X.
5430     Address immed;
5431     bool is_movz;
5432     typedef typename elfcpp::Elf_types<size>::Elf_Swxword SignedW;
5433     if (static_cast<SignedW>(x) >= 0)
5434       {
5435         immed = reloc_property->select_x_value(x);
5436         is_movz = true;
5437       }
5438     else
5439       {
5440         immed = reloc_property->select_x_value(~x);;
5441         is_movz = false;
5442       }
5443
5444     // Update movnz instruction.
5445     update_movnz(view, immed, is_movz);
5446
5447     // Do check overflow or alignment if needed.
5448     return (reloc_property->checkup_x_value(x)
5449             ? This::STATUS_OKAY
5450             : This::STATUS_OVERFLOW);
5451   }
5452
5453   static inline bool
5454   maybe_apply_stub(unsigned int,
5455                    const The_relocate_info*,
5456                    const The_rela&,
5457                    unsigned char*,
5458                    Address,
5459                    const Sized_symbol<size>*,
5460                    const Symbol_value<size>*,
5461                    const Sized_relobj_file<size, big_endian>*,
5462                    section_size_type);
5463
5464 };  // End of AArch64_relocate_functions
5465
5466
5467 // For a certain relocation type (usually jump/branch), test to see if the
5468 // destination needs a stub to fulfil. If so, re-route the destination of the
5469 // original instruction to the stub, note, at this time, the stub has already
5470 // been generated.
5471
5472 template<int size, bool big_endian>
5473 bool
5474 AArch64_relocate_functions<size, big_endian>::
5475 maybe_apply_stub(unsigned int r_type,
5476                  const The_relocate_info* relinfo,
5477                  const The_rela& rela,
5478                  unsigned char* view,
5479                  Address address,
5480                  const Sized_symbol<size>* gsym,
5481                  const Symbol_value<size>* psymval,
5482                  const Sized_relobj_file<size, big_endian>* object,
5483                  section_size_type current_group_size)
5484 {
5485   if (parameters->options().relocatable())
5486     return false;
5487
5488   typename elfcpp::Elf_types<size>::Elf_Swxword addend = rela.get_r_addend();
5489   Address branch_target = psymval->value(object, 0) + addend;
5490   int stub_type =
5491     The_reloc_stub::stub_type_for_reloc(r_type, address, branch_target);
5492   if (stub_type == ST_NONE)
5493     return false;
5494
5495   const The_aarch64_relobj* aarch64_relobj =
5496       static_cast<const The_aarch64_relobj*>(object);
5497   const AArch64_reloc_property* arp =
5498     aarch64_reloc_property_table->get_reloc_property(r_type);
5499   gold_assert(arp != NULL);
5500
5501   // We don't create stubs for undefined symbols, but do for weak.
5502   if (gsym
5503       && !gsym->use_plt_offset(arp->reference_flags())
5504       && gsym->is_undefined())
5505     {
5506       gold_debug(DEBUG_TARGET,
5507                  "stub: looking for a stub for undefined symbol %s in file %s",
5508                  gsym->name(), aarch64_relobj->name().c_str());
5509       return false;
5510     }
5511
5512   The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
5513   gold_assert(stub_table != NULL);
5514
5515   unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
5516   typename The_reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
5517   The_reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
5518   gold_assert(stub != NULL);
5519
5520   Address new_branch_target = stub_table->address() + stub->offset();
5521   typename elfcpp::Swap<size, big_endian>::Valtype branch_offset =
5522       new_branch_target - address;
5523   typename This::Status status = This::template
5524       rela_general<32>(view, branch_offset, 0, arp);
5525   if (status != This::STATUS_OKAY)
5526     gold_error(_("Stub is too far away, try a smaller value "
5527                  "for '--stub-group-size'. The current value is 0x%lx."),
5528                static_cast<unsigned long>(current_group_size));
5529   return true;
5530 }
5531
5532
5533 // Group input sections for stub generation.
5534 //
5535 // We group input sections in an output section so that the total size,
5536 // including any padding space due to alignment is smaller than GROUP_SIZE
5537 // unless the only input section in group is bigger than GROUP_SIZE already.
5538 // Then an ARM stub table is created to follow the last input section
5539 // in group.  For each group an ARM stub table is created an is placed
5540 // after the last group.  If STUB_ALWAYS_AFTER_BRANCH is false, we further
5541 // extend the group after the stub table.
5542
5543 template<int size, bool big_endian>
5544 void
5545 Target_aarch64<size, big_endian>::group_sections(
5546     Layout* layout,
5547     section_size_type group_size,
5548     bool stubs_always_after_branch,
5549     const Task* task)
5550 {
5551   // Group input sections and insert stub table
5552   Layout::Section_list section_list;
5553   layout->get_executable_sections(&section_list);
5554   for (Layout::Section_list::const_iterator p = section_list.begin();
5555        p != section_list.end();
5556        ++p)
5557     {
5558       AArch64_output_section<size, big_endian>* output_section =
5559           static_cast<AArch64_output_section<size, big_endian>*>(*p);
5560       output_section->group_sections(group_size, stubs_always_after_branch,
5561                                      this, task);
5562     }
5563 }
5564
5565
5566 // Find the AArch64_input_section object corresponding to the SHNDX-th input
5567 // section of RELOBJ.
5568
5569 template<int size, bool big_endian>
5570 AArch64_input_section<size, big_endian>*
5571 Target_aarch64<size, big_endian>::find_aarch64_input_section(
5572     Relobj* relobj, unsigned int shndx) const
5573 {
5574   Section_id sid(relobj, shndx);
5575   typename AArch64_input_section_map::const_iterator p =
5576     this->aarch64_input_section_map_.find(sid);
5577   return (p != this->aarch64_input_section_map_.end()) ? p->second : NULL;
5578 }
5579
5580
5581 // Make a new AArch64_input_section object.
5582
5583 template<int size, bool big_endian>
5584 AArch64_input_section<size, big_endian>*
5585 Target_aarch64<size, big_endian>::new_aarch64_input_section(
5586     Relobj* relobj, unsigned int shndx)
5587 {
5588   Section_id sid(relobj, shndx);
5589
5590   AArch64_input_section<size, big_endian>* input_section =
5591       new AArch64_input_section<size, big_endian>(relobj, shndx);
5592   input_section->init();
5593
5594   // Register new AArch64_input_section in map for look-up.
5595   std::pair<typename AArch64_input_section_map::iterator,bool> ins =
5596       this->aarch64_input_section_map_.insert(
5597           std::make_pair(sid, input_section));
5598
5599   // Make sure that it we have not created another AArch64_input_section
5600   // for this input section already.
5601   gold_assert(ins.second);
5602
5603   return input_section;
5604 }
5605
5606
5607 // Relaxation hook.  This is where we do stub generation.
5608
5609 template<int size, bool big_endian>
5610 bool
5611 Target_aarch64<size, big_endian>::do_relax(
5612     int pass,
5613     const Input_objects* input_objects,
5614     Symbol_table* symtab,
5615     Layout* layout ,
5616     const Task* task)
5617 {
5618   gold_assert(!parameters->options().relocatable());
5619   if (pass == 1)
5620     {
5621       // We don't handle negative stub_group_size right now.
5622       this->stub_group_size_ = abs(parameters->options().stub_group_size());
5623       if (this->stub_group_size_ == 1)
5624         {
5625           // Leave room for 4096 4-byte stub entries. If we exceed that, then we
5626           // will fail to link.  The user will have to relink with an explicit
5627           // group size option.
5628           this->stub_group_size_ = The_reloc_stub::MAX_BRANCH_OFFSET -
5629                                    4096 * 4;
5630         }
5631       group_sections(layout, this->stub_group_size_, true, task);
5632     }
5633   else
5634     {
5635       // If this is not the first pass, addresses and file offsets have
5636       // been reset at this point, set them here.
5637       for (Stub_table_iterator sp = this->stub_tables_.begin();
5638            sp != this->stub_tables_.end(); ++sp)
5639         {
5640           The_stub_table* stt = *sp;
5641           The_aarch64_input_section* owner = stt->owner();
5642           off_t off = align_address(owner->original_size(),
5643                                     stt->addralign());
5644           stt->set_address_and_file_offset(owner->address() + off,
5645                                            owner->offset() + off);
5646         }
5647     }
5648
5649   // Scan relocs for relocation stubs
5650   for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
5651        op != input_objects->relobj_end();
5652        ++op)
5653     {
5654       The_aarch64_relobj* aarch64_relobj =
5655           static_cast<The_aarch64_relobj*>(*op);
5656       // Lock the object so we can read from it.  This is only called
5657       // single-threaded from Layout::finalize, so it is OK to lock.
5658       Task_lock_obj<Object> tl(task, aarch64_relobj);
5659       aarch64_relobj->scan_sections_for_stubs(this, symtab, layout);
5660     }
5661
5662   bool any_stub_table_changed = false;
5663   for (Stub_table_iterator siter = this->stub_tables_.begin();
5664        siter != this->stub_tables_.end() && !any_stub_table_changed; ++siter)
5665     {
5666       The_stub_table* stub_table = *siter;
5667       if (stub_table->update_data_size_changed_p())
5668         {
5669           The_aarch64_input_section* owner = stub_table->owner();
5670           uint64_t address = owner->address();
5671           off_t offset = owner->offset();
5672           owner->reset_address_and_file_offset();
5673           owner->set_address_and_file_offset(address, offset);
5674
5675           any_stub_table_changed = true;
5676         }
5677     }
5678
5679   // Do not continue relaxation.
5680   bool continue_relaxation = any_stub_table_changed;
5681   if (!continue_relaxation)
5682     for (Stub_table_iterator sp = this->stub_tables_.begin();
5683          (sp != this->stub_tables_.end());
5684          ++sp)
5685       (*sp)->finalize_stubs();
5686
5687   return continue_relaxation;
5688 }
5689
5690
5691 // Make a new Stub_table.
5692
5693 template<int size, bool big_endian>
5694 Stub_table<size, big_endian>*
5695 Target_aarch64<size, big_endian>::new_stub_table(
5696     AArch64_input_section<size, big_endian>* owner)
5697 {
5698   Stub_table<size, big_endian>* stub_table =
5699       new Stub_table<size, big_endian>(owner);
5700   stub_table->set_address(align_address(
5701       owner->address() + owner->data_size(), 8));
5702   stub_table->set_file_offset(owner->offset() + owner->data_size());
5703   stub_table->finalize_data_size();
5704
5705   this->stub_tables_.push_back(stub_table);
5706
5707   return stub_table;
5708 }
5709
5710
5711 template<int size, bool big_endian>
5712 uint64_t
5713 Target_aarch64<size, big_endian>::do_reloc_addend(
5714     void* arg, unsigned int r_type, uint64_t) const
5715 {
5716   gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
5717   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
5718   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
5719   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
5720   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
5721   gold_assert(psymval->is_tls_symbol());
5722   // The value of a TLS symbol is the offset in the TLS segment.
5723   return psymval->value(ti.object, 0);
5724 }
5725
5726 // Return the number of entries in the PLT.
5727
5728 template<int size, bool big_endian>
5729 unsigned int
5730 Target_aarch64<size, big_endian>::plt_entry_count() const
5731 {
5732   if (this->plt_ == NULL)
5733     return 0;
5734   return this->plt_->entry_count();
5735 }
5736
5737 // Return the offset of the first non-reserved PLT entry.
5738
5739 template<int size, bool big_endian>
5740 unsigned int
5741 Target_aarch64<size, big_endian>::first_plt_entry_offset() const
5742 {
5743   return this->plt_->first_plt_entry_offset();
5744 }
5745
5746 // Return the size of each PLT entry.
5747
5748 template<int size, bool big_endian>
5749 unsigned int
5750 Target_aarch64<size, big_endian>::plt_entry_size() const
5751 {
5752   return this->plt_->get_plt_entry_size();
5753 }
5754
5755 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
5756
5757 template<int size, bool big_endian>
5758 void
5759 Target_aarch64<size, big_endian>::define_tls_base_symbol(
5760     Symbol_table* symtab, Layout* layout)
5761 {
5762   if (this->tls_base_symbol_defined_)
5763     return;
5764
5765   Output_segment* tls_segment = layout->tls_segment();
5766   if (tls_segment != NULL)
5767     {
5768       // _TLS_MODULE_BASE_ always points to the beginning of tls segment.
5769       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
5770                                        Symbol_table::PREDEFINED,
5771                                        tls_segment, 0, 0,
5772                                        elfcpp::STT_TLS,
5773                                        elfcpp::STB_LOCAL,
5774                                        elfcpp::STV_HIDDEN, 0,
5775                                        Symbol::SEGMENT_START,
5776                                        true);
5777     }
5778   this->tls_base_symbol_defined_ = true;
5779 }
5780
5781 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
5782
5783 template<int size, bool big_endian>
5784 void
5785 Target_aarch64<size, big_endian>::reserve_tlsdesc_entries(
5786     Symbol_table* symtab, Layout* layout)
5787 {
5788   if (this->plt_ == NULL)
5789     this->make_plt_section(symtab, layout);
5790
5791   if (!this->plt_->has_tlsdesc_entry())
5792     {
5793       // Allocate the TLSDESC_GOT entry.
5794       Output_data_got_aarch64<size, big_endian>* got =
5795           this->got_section(symtab, layout);
5796       unsigned int got_offset = got->add_constant(0);
5797
5798       // Allocate the TLSDESC_PLT entry.
5799       this->plt_->reserve_tlsdesc_entry(got_offset);
5800     }
5801 }
5802
5803 // Create a GOT entry for the TLS module index.
5804
5805 template<int size, bool big_endian>
5806 unsigned int
5807 Target_aarch64<size, big_endian>::got_mod_index_entry(
5808     Symbol_table* symtab, Layout* layout,
5809     Sized_relobj_file<size, big_endian>* object)
5810 {
5811   if (this->got_mod_index_offset_ == -1U)
5812     {
5813       gold_assert(symtab != NULL && layout != NULL && object != NULL);
5814       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
5815       Output_data_got_aarch64<size, big_endian>* got =
5816           this->got_section(symtab, layout);
5817       unsigned int got_offset = got->add_constant(0);
5818       rela_dyn->add_local(object, 0, elfcpp::R_AARCH64_TLS_DTPMOD64, got,
5819                           got_offset, 0);
5820       got->add_constant(0);
5821       this->got_mod_index_offset_ = got_offset;
5822     }
5823   return this->got_mod_index_offset_;
5824 }
5825
5826 // Optimize the TLS relocation type based on what we know about the
5827 // symbol.  IS_FINAL is true if the final address of this symbol is
5828 // known at link time.
5829
5830 template<int size, bool big_endian>
5831 tls::Tls_optimization
5832 Target_aarch64<size, big_endian>::optimize_tls_reloc(bool is_final,
5833                                                      int r_type)
5834 {
5835   // If we are generating a shared library, then we can't do anything
5836   // in the linker
5837   if (parameters->options().shared())
5838     return tls::TLSOPT_NONE;
5839
5840   switch (r_type)
5841     {
5842     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
5843     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
5844     case elfcpp::R_AARCH64_TLSDESC_LD_PREL19:
5845     case elfcpp::R_AARCH64_TLSDESC_ADR_PREL21:
5846     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
5847     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
5848     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
5849     case elfcpp::R_AARCH64_TLSDESC_OFF_G1:
5850     case elfcpp::R_AARCH64_TLSDESC_OFF_G0_NC:
5851     case elfcpp::R_AARCH64_TLSDESC_LDR:
5852     case elfcpp::R_AARCH64_TLSDESC_ADD:
5853     case elfcpp::R_AARCH64_TLSDESC_CALL:
5854       // These are General-Dynamic which permits fully general TLS
5855       // access.  Since we know that we are generating an executable,
5856       // we can convert this to Initial-Exec.  If we also know that
5857       // this is a local symbol, we can further switch to Local-Exec.
5858       if (is_final)
5859         return tls::TLSOPT_TO_LE;
5860       return tls::TLSOPT_TO_IE;
5861
5862     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
5863     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
5864     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
5865     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
5866     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
5867     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
5868       // These are Local-Dynamic, which refer to local symbols in the
5869       // dynamic TLS block. Since we know that we generating an
5870       // executable, we can switch to Local-Exec.
5871       return tls::TLSOPT_TO_LE;
5872
5873     case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G1:
5874     case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC:
5875     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
5876     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
5877     case elfcpp::R_AARCH64_TLSIE_LD_GOTTPREL_PREL19:
5878       // These are Initial-Exec relocs which get the thread offset
5879       // from the GOT. If we know that we are linking against the
5880       // local symbol, we can switch to Local-Exec, which links the
5881       // thread offset into the instruction.
5882       if (is_final)
5883         return tls::TLSOPT_TO_LE;
5884       return tls::TLSOPT_NONE;
5885
5886     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
5887     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
5888     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
5889     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
5890     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
5891     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
5892     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
5893     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
5894       // When we already have Local-Exec, there is nothing further we
5895       // can do.
5896       return tls::TLSOPT_NONE;
5897
5898     default:
5899       gold_unreachable();
5900     }
5901 }
5902
5903 // Returns true if this relocation type could be that of a function pointer.
5904
5905 template<int size, bool big_endian>
5906 inline bool
5907 Target_aarch64<size, big_endian>::Scan::possible_function_pointer_reloc(
5908   unsigned int r_type)
5909 {
5910   switch (r_type)
5911     {
5912     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
5913     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
5914     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
5915     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
5916     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
5917       {
5918         return true;
5919       }
5920     }
5921   return false;
5922 }
5923
5924 // For safe ICF, scan a relocation for a local symbol to check if it
5925 // corresponds to a function pointer being taken.  In that case mark
5926 // the function whose pointer was taken as not foldable.
5927
5928 template<int size, bool big_endian>
5929 inline bool
5930 Target_aarch64<size, big_endian>::Scan::local_reloc_may_be_function_pointer(
5931   Symbol_table* ,
5932   Layout* ,
5933   Target_aarch64<size, big_endian>* ,
5934   Sized_relobj_file<size, big_endian>* ,
5935   unsigned int ,
5936   Output_section* ,
5937   const elfcpp::Rela<size, big_endian>& ,
5938   unsigned int r_type,
5939   const elfcpp::Sym<size, big_endian>&)
5940 {
5941   // When building a shared library, do not fold any local symbols.
5942   return (parameters->options().shared()
5943           || possible_function_pointer_reloc(r_type));
5944 }
5945
5946 // For safe ICF, scan a relocation for a global symbol to check if it
5947 // corresponds to a function pointer being taken.  In that case mark
5948 // the function whose pointer was taken as not foldable.
5949
5950 template<int size, bool big_endian>
5951 inline bool
5952 Target_aarch64<size, big_endian>::Scan::global_reloc_may_be_function_pointer(
5953   Symbol_table* ,
5954   Layout* ,
5955   Target_aarch64<size, big_endian>* ,
5956   Sized_relobj_file<size, big_endian>* ,
5957   unsigned int ,
5958   Output_section* ,
5959   const elfcpp::Rela<size, big_endian>& ,
5960   unsigned int r_type,
5961   Symbol* gsym)
5962 {
5963   // When building a shared library, do not fold symbols whose visibility
5964   // is hidden, internal or protected.
5965   return ((parameters->options().shared()
5966            && (gsym->visibility() == elfcpp::STV_INTERNAL
5967                || gsym->visibility() == elfcpp::STV_PROTECTED
5968                || gsym->visibility() == elfcpp::STV_HIDDEN))
5969           || possible_function_pointer_reloc(r_type));
5970 }
5971
5972 // Report an unsupported relocation against a local symbol.
5973
5974 template<int size, bool big_endian>
5975 void
5976 Target_aarch64<size, big_endian>::Scan::unsupported_reloc_local(
5977      Sized_relobj_file<size, big_endian>* object,
5978      unsigned int r_type)
5979 {
5980   gold_error(_("%s: unsupported reloc %u against local symbol"),
5981              object->name().c_str(), r_type);
5982 }
5983
5984 // We are about to emit a dynamic relocation of type R_TYPE.  If the
5985 // dynamic linker does not support it, issue an error.
5986
5987 template<int size, bool big_endian>
5988 void
5989 Target_aarch64<size, big_endian>::Scan::check_non_pic(Relobj* object,
5990                                                       unsigned int r_type)
5991 {
5992   gold_assert(r_type != elfcpp::R_AARCH64_NONE);
5993
5994   switch (r_type)
5995     {
5996     // These are the relocation types supported by glibc for AARCH64.
5997     case elfcpp::R_AARCH64_NONE:
5998     case elfcpp::R_AARCH64_COPY:
5999     case elfcpp::R_AARCH64_GLOB_DAT:
6000     case elfcpp::R_AARCH64_JUMP_SLOT:
6001     case elfcpp::R_AARCH64_RELATIVE:
6002     case elfcpp::R_AARCH64_TLS_DTPREL64:
6003     case elfcpp::R_AARCH64_TLS_DTPMOD64:
6004     case elfcpp::R_AARCH64_TLS_TPREL64:
6005     case elfcpp::R_AARCH64_TLSDESC:
6006     case elfcpp::R_AARCH64_IRELATIVE:
6007     case elfcpp::R_AARCH64_ABS32:
6008     case elfcpp::R_AARCH64_ABS64:
6009       return;
6010
6011     default:
6012       break;
6013     }
6014
6015   // This prevents us from issuing more than one error per reloc
6016   // section. But we can still wind up issuing more than one
6017   // error per object file.
6018   if (this->issued_non_pic_error_)
6019     return;
6020   gold_assert(parameters->options().output_is_position_independent());
6021   object->error(_("requires unsupported dynamic reloc; "
6022                   "recompile with -fPIC"));
6023   this->issued_non_pic_error_ = true;
6024   return;
6025 }
6026
6027 // Return whether we need to make a PLT entry for a relocation of the
6028 // given type against a STT_GNU_IFUNC symbol.
6029
6030 template<int size, bool big_endian>
6031 bool
6032 Target_aarch64<size, big_endian>::Scan::reloc_needs_plt_for_ifunc(
6033     Sized_relobj_file<size, big_endian>* object,
6034     unsigned int r_type)
6035 {
6036   const AArch64_reloc_property* arp =
6037       aarch64_reloc_property_table->get_reloc_property(r_type);
6038   gold_assert(arp != NULL);
6039
6040   int flags = arp->reference_flags();
6041   if (flags & Symbol::TLS_REF)
6042     {
6043       gold_error(_("%s: unsupported TLS reloc %s for IFUNC symbol"),
6044                  object->name().c_str(), arp->name().c_str());
6045       return false;
6046     }
6047   return flags != 0;
6048 }
6049
6050 // Scan a relocation for a local symbol.
6051
6052 template<int size, bool big_endian>
6053 inline void
6054 Target_aarch64<size, big_endian>::Scan::local(
6055     Symbol_table* symtab,
6056     Layout* layout,
6057     Target_aarch64<size, big_endian>* target,
6058     Sized_relobj_file<size, big_endian>* object,
6059     unsigned int data_shndx,
6060     Output_section* output_section,
6061     const elfcpp::Rela<size, big_endian>& rela,
6062     unsigned int r_type,
6063     const elfcpp::Sym<size, big_endian>& lsym,
6064     bool is_discarded)
6065 {
6066   if (is_discarded)
6067     return;
6068
6069   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
6070       Reloc_section;
6071   unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
6072
6073   // A local STT_GNU_IFUNC symbol may require a PLT entry.
6074   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
6075   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
6076     target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
6077
6078   switch (r_type)
6079     {
6080     case elfcpp::R_AARCH64_NONE:
6081       break;
6082
6083     case elfcpp::R_AARCH64_ABS32:
6084     case elfcpp::R_AARCH64_ABS16:
6085       if (parameters->options().output_is_position_independent())
6086         {
6087           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6088                      object->name().c_str(), r_type);
6089         }
6090       break;
6091
6092     case elfcpp::R_AARCH64_ABS64:
6093       // If building a shared library or pie, we need to mark this as a dynmic
6094       // reloction, so that the dynamic loader can relocate it.
6095       if (parameters->options().output_is_position_independent())
6096         {
6097           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6098           rela_dyn->add_local_relative(object, r_sym,
6099                                        elfcpp::R_AARCH64_RELATIVE,
6100                                        output_section,
6101                                        data_shndx,
6102                                        rela.get_r_offset(),
6103                                        rela.get_r_addend(),
6104                                        is_ifunc);
6105         }
6106       break;
6107
6108     case elfcpp::R_AARCH64_PREL64:
6109     case elfcpp::R_AARCH64_PREL32:
6110     case elfcpp::R_AARCH64_PREL16:
6111       break;
6112
6113     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
6114     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
6115     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
6116       // The above relocations are used to access GOT entries.
6117       {
6118         Output_data_got_aarch64<size, big_endian>* got =
6119             target->got_section(symtab, layout);
6120         bool is_new = false;
6121         // This symbol requires a GOT entry.
6122         if (is_ifunc)
6123           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
6124         else
6125           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
6126         if (is_new && parameters->options().output_is_position_independent())
6127           target->rela_dyn_section(layout)->
6128             add_local_relative(object,
6129                                r_sym,
6130                                elfcpp::R_AARCH64_RELATIVE,
6131                                got,
6132                                object->local_got_offset(r_sym,
6133                                                         GOT_TYPE_STANDARD),
6134                                0,
6135                                false);
6136       }
6137       break;
6138
6139     case elfcpp::R_AARCH64_MOVW_UABS_G0:        // 263
6140     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:     // 264
6141     case elfcpp::R_AARCH64_MOVW_UABS_G1:        // 265
6142     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:     // 266
6143     case elfcpp::R_AARCH64_MOVW_UABS_G2:        // 267
6144     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:     // 268
6145     case elfcpp::R_AARCH64_MOVW_UABS_G3:        // 269
6146     case elfcpp::R_AARCH64_MOVW_SABS_G0:        // 270
6147     case elfcpp::R_AARCH64_MOVW_SABS_G1:        // 271
6148     case elfcpp::R_AARCH64_MOVW_SABS_G2:        // 272
6149       if (parameters->options().output_is_position_independent())
6150         {
6151           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6152                      object->name().c_str(), r_type);
6153         }
6154       break;
6155
6156     case elfcpp::R_AARCH64_LD_PREL_LO19:        // 273
6157     case elfcpp::R_AARCH64_ADR_PREL_LO21:       // 274
6158     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:    // 275
6159     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
6160     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:     // 277
6161     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:   // 278
6162     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:  // 284
6163     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:  // 285
6164     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:  // 286
6165     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
6166        break;
6167
6168     // Control flow, pc-relative. We don't need to do anything for a relative
6169     // addressing relocation against a local symbol if it does not reference
6170     // the GOT.
6171     case elfcpp::R_AARCH64_TSTBR14:
6172     case elfcpp::R_AARCH64_CONDBR19:
6173     case elfcpp::R_AARCH64_JUMP26:
6174     case elfcpp::R_AARCH64_CALL26:
6175       break;
6176
6177     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
6178     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
6179       {
6180         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6181           optimize_tls_reloc(!parameters->options().shared(), r_type);
6182         if (tlsopt == tls::TLSOPT_TO_LE)
6183           break;
6184
6185         layout->set_has_static_tls();
6186         // Create a GOT entry for the tp-relative offset.
6187         if (!parameters->doing_static_link())
6188           {
6189             Output_data_got_aarch64<size, big_endian>* got =
6190                 target->got_section(symtab, layout);
6191             got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
6192                                     target->rela_dyn_section(layout),
6193                                     elfcpp::R_AARCH64_TLS_TPREL64);
6194           }
6195         else if (!object->local_has_got_offset(r_sym,
6196                                                GOT_TYPE_TLS_OFFSET))
6197           {
6198             Output_data_got_aarch64<size, big_endian>* got =
6199                 target->got_section(symtab, layout);
6200             got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
6201             unsigned int got_offset =
6202                 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
6203             const elfcpp::Elf_Xword addend = rela.get_r_addend();
6204             gold_assert(addend == 0);
6205             got->add_static_reloc(got_offset, elfcpp::R_AARCH64_TLS_TPREL64,
6206                                   object, r_sym);
6207           }
6208       }
6209       break;
6210
6211     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
6212     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
6213       {
6214         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6215             optimize_tls_reloc(!parameters->options().shared(), r_type);
6216         if (tlsopt == tls::TLSOPT_TO_LE)
6217           {
6218             layout->set_has_static_tls();
6219             break;
6220           }
6221         gold_assert(tlsopt == tls::TLSOPT_NONE);
6222
6223         Output_data_got_aarch64<size, big_endian>* got =
6224             target->got_section(symtab, layout);
6225         got->add_local_pair_with_rel(object,r_sym, data_shndx,
6226                                      GOT_TYPE_TLS_PAIR,
6227                                      target->rela_dyn_section(layout),
6228                                      elfcpp::R_AARCH64_TLS_DTPMOD64);
6229       }
6230       break;
6231
6232     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
6233     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
6234     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
6235     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
6236     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
6237     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
6238     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
6239     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
6240       {
6241         layout->set_has_static_tls();
6242         bool output_is_shared = parameters->options().shared();
6243         if (output_is_shared)
6244           gold_error(_("%s: unsupported TLSLE reloc %u in shared code."),
6245                      object->name().c_str(), r_type);
6246       }
6247       break;
6248
6249     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
6250     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
6251       {
6252         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6253             optimize_tls_reloc(!parameters->options().shared(), r_type);
6254         if (tlsopt == tls::TLSOPT_NONE)
6255           {
6256             // Create a GOT entry for the module index.
6257             target->got_mod_index_entry(symtab, layout, object);
6258           }
6259         else if (tlsopt != tls::TLSOPT_TO_LE)
6260           unsupported_reloc_local(object, r_type);
6261       }
6262       break;
6263
6264     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
6265     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
6266     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
6267     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
6268       break;
6269
6270     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
6271     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
6272     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
6273       {
6274         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6275             optimize_tls_reloc(!parameters->options().shared(), r_type);
6276         target->define_tls_base_symbol(symtab, layout);
6277         if (tlsopt == tls::TLSOPT_NONE)
6278           {
6279             // Create reserved PLT and GOT entries for the resolver.
6280             target->reserve_tlsdesc_entries(symtab, layout);
6281
6282             // Generate a double GOT entry with an R_AARCH64_TLSDESC reloc.
6283             // The R_AARCH64_TLSDESC reloc is resolved lazily, so the GOT
6284             // entry needs to be in an area in .got.plt, not .got. Call
6285             // got_section to make sure the section has been created.
6286             target->got_section(symtab, layout);
6287             Output_data_got<size, big_endian>* got =
6288                 target->got_tlsdesc_section();
6289             unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
6290             if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
6291               {
6292                 unsigned int got_offset = got->add_constant(0);
6293                 got->add_constant(0);
6294                 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
6295                                              got_offset);
6296                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
6297                 // We store the arguments we need in a vector, and use
6298                 // the index into the vector as the parameter to pass
6299                 // to the target specific routines.
6300                 uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
6301                 void* arg = reinterpret_cast<void*>(intarg);
6302                 rt->add_target_specific(elfcpp::R_AARCH64_TLSDESC, arg,
6303                                         got, got_offset, 0);
6304               }
6305           }
6306         else if (tlsopt != tls::TLSOPT_TO_LE)
6307           unsupported_reloc_local(object, r_type);
6308       }
6309       break;
6310
6311     case elfcpp::R_AARCH64_TLSDESC_CALL:
6312       break;
6313
6314     default:
6315       unsupported_reloc_local(object, r_type);
6316     }
6317 }
6318
6319
6320 // Report an unsupported relocation against a global symbol.
6321
6322 template<int size, bool big_endian>
6323 void
6324 Target_aarch64<size, big_endian>::Scan::unsupported_reloc_global(
6325     Sized_relobj_file<size, big_endian>* object,
6326     unsigned int r_type,
6327     Symbol* gsym)
6328 {
6329   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
6330              object->name().c_str(), r_type, gsym->demangled_name().c_str());
6331 }
6332
6333 template<int size, bool big_endian>
6334 inline void
6335 Target_aarch64<size, big_endian>::Scan::global(
6336     Symbol_table* symtab,
6337     Layout* layout,
6338     Target_aarch64<size, big_endian>* target,
6339     Sized_relobj_file<size, big_endian> * object,
6340     unsigned int data_shndx,
6341     Output_section* output_section,
6342     const elfcpp::Rela<size, big_endian>& rela,
6343     unsigned int r_type,
6344     Symbol* gsym)
6345 {
6346   // A STT_GNU_IFUNC symbol may require a PLT entry.
6347   if (gsym->type() == elfcpp::STT_GNU_IFUNC
6348       && this->reloc_needs_plt_for_ifunc(object, r_type))
6349     target->make_plt_entry(symtab, layout, gsym);
6350
6351   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
6352     Reloc_section;
6353   const AArch64_reloc_property* arp =
6354       aarch64_reloc_property_table->get_reloc_property(r_type);
6355   gold_assert(arp != NULL);
6356
6357   switch (r_type)
6358     {
6359     case elfcpp::R_AARCH64_NONE:
6360       break;
6361
6362     case elfcpp::R_AARCH64_ABS16:
6363     case elfcpp::R_AARCH64_ABS32:
6364     case elfcpp::R_AARCH64_ABS64:
6365       {
6366         // Make a PLT entry if necessary.
6367         if (gsym->needs_plt_entry())
6368           {
6369             target->make_plt_entry(symtab, layout, gsym);
6370             // Since this is not a PC-relative relocation, we may be
6371             // taking the address of a function. In that case we need to
6372             // set the entry in the dynamic symbol table to the address of
6373             // the PLT entry.
6374             if (gsym->is_from_dynobj() && !parameters->options().shared())
6375               gsym->set_needs_dynsym_value();
6376           }
6377         // Make a dynamic relocation if necessary.
6378         if (gsym->needs_dynamic_reloc(arp->reference_flags()))
6379           {
6380             if (!parameters->options().output_is_position_independent()
6381                 && gsym->may_need_copy_reloc())
6382               {
6383                 target->copy_reloc(symtab, layout, object,
6384                                    data_shndx, output_section, gsym, rela);
6385               }
6386             else if (r_type == elfcpp::R_AARCH64_ABS64
6387                      && gsym->type() == elfcpp::STT_GNU_IFUNC
6388                      && gsym->can_use_relative_reloc(false)
6389                      && !gsym->is_from_dynobj()
6390                      && !gsym->is_undefined()
6391                      && !gsym->is_preemptible())
6392               {
6393                 // Use an IRELATIVE reloc for a locally defined STT_GNU_IFUNC
6394                 // symbol. This makes a function address in a PIE executable
6395                 // match the address in a shared library that it links against.
6396                 Reloc_section* rela_dyn =
6397                     target->rela_irelative_section(layout);
6398                 unsigned int r_type = elfcpp::R_AARCH64_IRELATIVE;
6399                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
6400                                                        output_section, object,
6401                                                        data_shndx,
6402                                                        rela.get_r_offset(),
6403                                                        rela.get_r_addend());
6404               }
6405             else if (r_type == elfcpp::R_AARCH64_ABS64
6406                      && gsym->can_use_relative_reloc(false))
6407               {
6408                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6409                 rela_dyn->add_global_relative(gsym,
6410                                               elfcpp::R_AARCH64_RELATIVE,
6411                                               output_section,
6412                                               object,
6413                                               data_shndx,
6414                                               rela.get_r_offset(),
6415                                               rela.get_r_addend(),
6416                                               false);
6417               }
6418             else
6419               {
6420                 check_non_pic(object, r_type);
6421                 Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>*
6422                     rela_dyn = target->rela_dyn_section(layout);
6423                 rela_dyn->add_global(
6424                   gsym, r_type, output_section, object,
6425                   data_shndx, rela.get_r_offset(),rela.get_r_addend());
6426               }
6427           }
6428       }
6429       break;
6430
6431     case elfcpp::R_AARCH64_PREL16:
6432     case elfcpp::R_AARCH64_PREL32:
6433     case elfcpp::R_AARCH64_PREL64:
6434       // This is used to fill the GOT absolute address.
6435       if (gsym->needs_plt_entry())
6436         {
6437           target->make_plt_entry(symtab, layout, gsym);
6438         }
6439       break;
6440
6441     case elfcpp::R_AARCH64_MOVW_UABS_G0:        // 263
6442     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:     // 264
6443     case elfcpp::R_AARCH64_MOVW_UABS_G1:        // 265
6444     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:     // 266
6445     case elfcpp::R_AARCH64_MOVW_UABS_G2:        // 267
6446     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:     // 268
6447     case elfcpp::R_AARCH64_MOVW_UABS_G3:        // 269
6448     case elfcpp::R_AARCH64_MOVW_SABS_G0:        // 270
6449     case elfcpp::R_AARCH64_MOVW_SABS_G1:        // 271
6450     case elfcpp::R_AARCH64_MOVW_SABS_G2:        // 272
6451       if (parameters->options().output_is_position_independent())
6452         {
6453           gold_error(_("%s: unsupported reloc %u in pos independent link."),
6454                      object->name().c_str(), r_type);
6455         }
6456       break;
6457
6458     case elfcpp::R_AARCH64_LD_PREL_LO19:        // 273
6459     case elfcpp::R_AARCH64_ADR_PREL_LO21:       // 274
6460     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:    // 275
6461     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
6462     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:     // 277
6463     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:   // 278
6464     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:  // 284
6465     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:  // 285
6466     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:  // 286
6467     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
6468       {
6469         if (gsym->needs_plt_entry())
6470           target->make_plt_entry(symtab, layout, gsym);
6471         // Make a dynamic relocation if necessary.
6472         if (gsym->needs_dynamic_reloc(arp->reference_flags()))
6473           {
6474             if (parameters->options().output_is_executable()
6475                 && gsym->may_need_copy_reloc())
6476               {
6477                 target->copy_reloc(symtab, layout, object,
6478                                    data_shndx, output_section, gsym, rela);
6479               }
6480           }
6481         break;
6482       }
6483
6484     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
6485     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
6486     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
6487       {
6488         // The above relocations are used to access GOT entries.
6489         // Note a GOT entry is an *address* to a symbol.
6490         // The symbol requires a GOT entry
6491         Output_data_got_aarch64<size, big_endian>* got =
6492           target->got_section(symtab, layout);
6493         if (gsym->final_value_is_known())
6494           {
6495             // For a STT_GNU_IFUNC symbol we want the PLT address.
6496             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
6497               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
6498             else
6499               got->add_global(gsym, GOT_TYPE_STANDARD);
6500           }
6501         else
6502           {
6503             // If this symbol is not fully resolved, we need to add a dynamic
6504             // relocation for it.
6505             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
6506
6507             // Use a GLOB_DAT rather than a RELATIVE reloc if:
6508             //
6509             // 1) The symbol may be defined in some other module.
6510             // 2) We are building a shared library and this is a protected
6511             // symbol; using GLOB_DAT means that the dynamic linker can use
6512             // the address of the PLT in the main executable when appropriate
6513             // so that function address comparisons work.
6514             // 3) This is a STT_GNU_IFUNC symbol in position dependent code,
6515             // again so that function address comparisons work.
6516             if (gsym->is_from_dynobj()
6517                 || gsym->is_undefined()
6518                 || gsym->is_preemptible()
6519                 || (gsym->visibility() == elfcpp::STV_PROTECTED
6520                     && parameters->options().shared())
6521                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
6522                     && parameters->options().output_is_position_independent()))
6523               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
6524                                        rela_dyn, elfcpp::R_AARCH64_GLOB_DAT);
6525             else
6526               {
6527                 // For a STT_GNU_IFUNC symbol we want to write the PLT
6528                 // offset into the GOT, so that function pointer
6529                 // comparisons work correctly.
6530                 bool is_new;
6531                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
6532                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
6533                 else
6534                   {
6535                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
6536                     // Tell the dynamic linker to use the PLT address
6537                     // when resolving relocations.
6538                     if (gsym->is_from_dynobj()
6539                         && !parameters->options().shared())
6540                       gsym->set_needs_dynsym_value();
6541                   }
6542                 if (is_new)
6543                   {
6544                     rela_dyn->add_global_relative(
6545                         gsym, elfcpp::R_AARCH64_RELATIVE,
6546                         got,
6547                         gsym->got_offset(GOT_TYPE_STANDARD),
6548                         0,
6549                         false);
6550                   }
6551               }
6552           }
6553         break;
6554       }
6555
6556     case elfcpp::R_AARCH64_TSTBR14:
6557     case elfcpp::R_AARCH64_CONDBR19:
6558     case elfcpp::R_AARCH64_JUMP26:
6559     case elfcpp::R_AARCH64_CALL26:
6560       {
6561         if (gsym->final_value_is_known())
6562           break;
6563
6564         if (gsym->is_defined() &&
6565             !gsym->is_from_dynobj() &&
6566             !gsym->is_preemptible())
6567           break;
6568
6569         // Make plt entry for function call.
6570         target->make_plt_entry(symtab, layout, gsym);
6571         break;
6572       }
6573
6574     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
6575     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:  // General dynamic
6576       {
6577         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6578             optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6579         if (tlsopt == tls::TLSOPT_TO_LE)
6580           {
6581             layout->set_has_static_tls();
6582             break;
6583           }
6584         gold_assert(tlsopt == tls::TLSOPT_NONE);
6585
6586         // General dynamic.
6587         Output_data_got_aarch64<size, big_endian>* got =
6588             target->got_section(symtab, layout);
6589         // Create 2 consecutive entries for module index and offset.
6590         got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
6591                                       target->rela_dyn_section(layout),
6592                                       elfcpp::R_AARCH64_TLS_DTPMOD64,
6593                                       elfcpp::R_AARCH64_TLS_DTPREL64);
6594       }
6595       break;
6596
6597     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
6598     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:  // Local dynamic
6599       {
6600         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6601             optimize_tls_reloc(!parameters->options().shared(), r_type);
6602         if (tlsopt == tls::TLSOPT_NONE)
6603           {
6604             // Create a GOT entry for the module index.
6605             target->got_mod_index_entry(symtab, layout, object);
6606           }
6607         else if (tlsopt != tls::TLSOPT_TO_LE)
6608           unsupported_reloc_local(object, r_type);
6609       }
6610       break;
6611
6612     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
6613     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
6614     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
6615     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:  // Other local dynamic
6616       break;
6617
6618     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
6619     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:  // Initial executable
6620       {
6621         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6622           optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6623         if (tlsopt == tls::TLSOPT_TO_LE)
6624           break;
6625
6626         layout->set_has_static_tls();
6627         // Create a GOT entry for the tp-relative offset.
6628         Output_data_got_aarch64<size, big_endian>* got
6629           = target->got_section(symtab, layout);
6630         if (!parameters->doing_static_link())
6631           {
6632             got->add_global_with_rel(
6633               gsym, GOT_TYPE_TLS_OFFSET,
6634               target->rela_dyn_section(layout),
6635               elfcpp::R_AARCH64_TLS_TPREL64);
6636           }
6637         if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
6638           {
6639             got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
6640             unsigned int got_offset =
6641               gsym->got_offset(GOT_TYPE_TLS_OFFSET);
6642             const elfcpp::Elf_Xword addend = rela.get_r_addend();
6643             gold_assert(addend == 0);
6644             got->add_static_reloc(got_offset,
6645                                   elfcpp::R_AARCH64_TLS_TPREL64, gsym);
6646           }
6647       }
6648       break;
6649
6650     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
6651     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
6652     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
6653     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
6654     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
6655     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
6656     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
6657     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:  // Local executable
6658       layout->set_has_static_tls();
6659       if (parameters->options().shared())
6660         gold_error(_("%s: unsupported TLSLE reloc type %u in shared objects."),
6661                    object->name().c_str(), r_type);
6662       break;
6663
6664     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
6665     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
6666     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:  // TLS descriptor
6667       {
6668         target->define_tls_base_symbol(symtab, layout);
6669         tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
6670             optimize_tls_reloc(gsym->final_value_is_known(), r_type);
6671         if (tlsopt == tls::TLSOPT_NONE)
6672           {
6673             // Create reserved PLT and GOT entries for the resolver.
6674             target->reserve_tlsdesc_entries(symtab, layout);
6675
6676             // Create a double GOT entry with an R_AARCH64_TLSDESC
6677             // relocation. The R_AARCH64_TLSDESC is resolved lazily, so the GOT
6678             // entry needs to be in an area in .got.plt, not .got. Call
6679             // got_section to make sure the section has been created.
6680             target->got_section(symtab, layout);
6681             Output_data_got<size, big_endian>* got =
6682                 target->got_tlsdesc_section();
6683             Reloc_section* rt = target->rela_tlsdesc_section(layout);
6684             got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
6685                                           elfcpp::R_AARCH64_TLSDESC, 0);
6686           }
6687         else if (tlsopt == tls::TLSOPT_TO_IE)
6688           {
6689             // Create a GOT entry for the tp-relative offset.
6690             Output_data_got<size, big_endian>* got
6691                 = target->got_section(symtab, layout);
6692             got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
6693                                      target->rela_dyn_section(layout),
6694                                      elfcpp::R_AARCH64_TLS_TPREL64);
6695           }
6696         else if (tlsopt != tls::TLSOPT_TO_LE)
6697           unsupported_reloc_global(object, r_type, gsym);
6698       }
6699       break;
6700
6701     case elfcpp::R_AARCH64_TLSDESC_CALL:
6702       break;
6703
6704     default:
6705       gold_error(_("%s: unsupported reloc type in global scan"),
6706                  aarch64_reloc_property_table->
6707                  reloc_name_in_error_message(r_type).c_str());
6708     }
6709   return;
6710 }  // End of Scan::global
6711
6712
6713 // Create the PLT section.
6714 template<int size, bool big_endian>
6715 void
6716 Target_aarch64<size, big_endian>::make_plt_section(
6717   Symbol_table* symtab, Layout* layout)
6718 {
6719   if (this->plt_ == NULL)
6720     {
6721       // Create the GOT section first.
6722       this->got_section(symtab, layout);
6723
6724       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
6725                                        this->got_irelative_);
6726
6727       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
6728                                       (elfcpp::SHF_ALLOC
6729                                        | elfcpp::SHF_EXECINSTR),
6730                                       this->plt_, ORDER_PLT, false);
6731
6732       // Make the sh_info field of .rela.plt point to .plt.
6733       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
6734       rela_plt_os->set_info_section(this->plt_->output_section());
6735     }
6736 }
6737
6738 // Return the section for TLSDESC relocations.
6739
6740 template<int size, bool big_endian>
6741 typename Target_aarch64<size, big_endian>::Reloc_section*
6742 Target_aarch64<size, big_endian>::rela_tlsdesc_section(Layout* layout) const
6743 {
6744   return this->plt_section()->rela_tlsdesc(layout);
6745 }
6746
6747 // Create a PLT entry for a global symbol.
6748
6749 template<int size, bool big_endian>
6750 void
6751 Target_aarch64<size, big_endian>::make_plt_entry(
6752     Symbol_table* symtab,
6753     Layout* layout,
6754     Symbol* gsym)
6755 {
6756   if (gsym->has_plt_offset())
6757     return;
6758
6759   if (this->plt_ == NULL)
6760     this->make_plt_section(symtab, layout);
6761
6762   this->plt_->add_entry(symtab, layout, gsym);
6763 }
6764
6765 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
6766
6767 template<int size, bool big_endian>
6768 void
6769 Target_aarch64<size, big_endian>::make_local_ifunc_plt_entry(
6770     Symbol_table* symtab, Layout* layout,
6771     Sized_relobj_file<size, big_endian>* relobj,
6772     unsigned int local_sym_index)
6773 {
6774   if (relobj->local_has_plt_offset(local_sym_index))
6775     return;
6776   if (this->plt_ == NULL)
6777     this->make_plt_section(symtab, layout);
6778   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
6779                                                               relobj,
6780                                                               local_sym_index);
6781   relobj->set_local_plt_offset(local_sym_index, plt_offset);
6782 }
6783
6784 template<int size, bool big_endian>
6785 void
6786 Target_aarch64<size, big_endian>::gc_process_relocs(
6787     Symbol_table* symtab,
6788     Layout* layout,
6789     Sized_relobj_file<size, big_endian>* object,
6790     unsigned int data_shndx,
6791     unsigned int sh_type,
6792     const unsigned char* prelocs,
6793     size_t reloc_count,
6794     Output_section* output_section,
6795     bool needs_special_offset_handling,
6796     size_t local_symbol_count,
6797     const unsigned char* plocal_symbols)
6798 {
6799   typedef Target_aarch64<size, big_endian> Aarch64;
6800   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
6801       Classify_reloc;
6802
6803   if (sh_type == elfcpp::SHT_REL)
6804     {
6805       return;
6806     }
6807
6808   gold::gc_process_relocs<size, big_endian, Aarch64, Scan, Classify_reloc>(
6809     symtab,
6810     layout,
6811     this,
6812     object,
6813     data_shndx,
6814     prelocs,
6815     reloc_count,
6816     output_section,
6817     needs_special_offset_handling,
6818     local_symbol_count,
6819     plocal_symbols);
6820 }
6821
6822 // Scan relocations for a section.
6823
6824 template<int size, bool big_endian>
6825 void
6826 Target_aarch64<size, big_endian>::scan_relocs(
6827     Symbol_table* symtab,
6828     Layout* layout,
6829     Sized_relobj_file<size, big_endian>* object,
6830     unsigned int data_shndx,
6831     unsigned int sh_type,
6832     const unsigned char* prelocs,
6833     size_t reloc_count,
6834     Output_section* output_section,
6835     bool needs_special_offset_handling,
6836     size_t local_symbol_count,
6837     const unsigned char* plocal_symbols)
6838 {
6839   typedef Target_aarch64<size, big_endian> Aarch64;
6840   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
6841       Classify_reloc;
6842
6843   if (sh_type == elfcpp::SHT_REL)
6844     {
6845       gold_error(_("%s: unsupported REL reloc section"),
6846                  object->name().c_str());
6847       return;
6848     }
6849
6850   gold::scan_relocs<size, big_endian, Aarch64, Scan, Classify_reloc>(
6851     symtab,
6852     layout,
6853     this,
6854     object,
6855     data_shndx,
6856     prelocs,
6857     reloc_count,
6858     output_section,
6859     needs_special_offset_handling,
6860     local_symbol_count,
6861     plocal_symbols);
6862 }
6863
6864 // Return the value to use for a dynamic which requires special
6865 // treatment.  This is how we support equality comparisons of function
6866 // pointers across shared library boundaries, as described in the
6867 // processor specific ABI supplement.
6868
6869 template<int size, bool big_endian>
6870 uint64_t
6871 Target_aarch64<size, big_endian>::do_dynsym_value(const Symbol* gsym) const
6872 {
6873   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
6874   return this->plt_address_for_global(gsym);
6875 }
6876
6877
6878 // Finalize the sections.
6879
6880 template<int size, bool big_endian>
6881 void
6882 Target_aarch64<size, big_endian>::do_finalize_sections(
6883     Layout* layout,
6884     const Input_objects*,
6885     Symbol_table* symtab)
6886 {
6887   const Reloc_section* rel_plt = (this->plt_ == NULL
6888                                   ? NULL
6889                                   : this->plt_->rela_plt());
6890   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
6891                                   this->rela_dyn_, true, false);
6892
6893   // Emit any relocs we saved in an attempt to avoid generating COPY
6894   // relocs.
6895   if (this->copy_relocs_.any_saved_relocs())
6896     this->copy_relocs_.emit(this->rela_dyn_section(layout));
6897
6898   // Fill in some more dynamic tags.
6899   Output_data_dynamic* const odyn = layout->dynamic_data();
6900   if (odyn != NULL)
6901     {
6902       if (this->plt_ != NULL
6903           && this->plt_->output_section() != NULL
6904           && this->plt_ ->has_tlsdesc_entry())
6905         {
6906           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
6907           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
6908           this->got_->finalize_data_size();
6909           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
6910                                         this->plt_, plt_offset);
6911           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
6912                                         this->got_, got_offset);
6913         }
6914     }
6915
6916   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
6917   // the .got.plt section.
6918   Symbol* sym = this->global_offset_table_;
6919   if (sym != NULL)
6920     {
6921       uint64_t data_size = this->got_plt_->current_data_size();
6922       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
6923
6924       // If the .got section is more than 0x8000 bytes, we add
6925       // 0x8000 to the value of _GLOBAL_OFFSET_TABLE_, so that 16
6926       // bit relocations have a greater chance of working.
6927       if (data_size >= 0x8000)
6928         symtab->get_sized_symbol<size>(sym)->set_value(
6929           symtab->get_sized_symbol<size>(sym)->value() + 0x8000);
6930     }
6931
6932   if (parameters->doing_static_link()
6933       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
6934     {
6935       // If linking statically, make sure that the __rela_iplt symbols
6936       // were defined if necessary, even if we didn't create a PLT.
6937       static const Define_symbol_in_segment syms[] =
6938         {
6939           {
6940             "__rela_iplt_start",        // name
6941             elfcpp::PT_LOAD,            // segment_type
6942             elfcpp::PF_W,               // segment_flags_set
6943             elfcpp::PF(0),              // segment_flags_clear
6944             0,                          // value
6945             0,                          // size
6946             elfcpp::STT_NOTYPE,         // type
6947             elfcpp::STB_GLOBAL,         // binding
6948             elfcpp::STV_HIDDEN,         // visibility
6949             0,                          // nonvis
6950             Symbol::SEGMENT_START,      // offset_from_base
6951             true                        // only_if_ref
6952           },
6953           {
6954             "__rela_iplt_end",          // name
6955             elfcpp::PT_LOAD,            // segment_type
6956             elfcpp::PF_W,               // segment_flags_set
6957             elfcpp::PF(0),              // segment_flags_clear
6958             0,                          // value
6959             0,                          // size
6960             elfcpp::STT_NOTYPE,         // type
6961             elfcpp::STB_GLOBAL,         // binding
6962             elfcpp::STV_HIDDEN,         // visibility
6963             0,                          // nonvis
6964             Symbol::SEGMENT_START,      // offset_from_base
6965             true                        // only_if_ref
6966           }
6967         };
6968
6969       symtab->define_symbols(layout, 2, syms,
6970                              layout->script_options()->saw_sections_clause());
6971     }
6972
6973   return;
6974 }
6975
6976 // Perform a relocation.
6977
6978 template<int size, bool big_endian>
6979 inline bool
6980 Target_aarch64<size, big_endian>::Relocate::relocate(
6981     const Relocate_info<size, big_endian>* relinfo,
6982     unsigned int,
6983     Target_aarch64<size, big_endian>* target,
6984     Output_section* ,
6985     size_t relnum,
6986     const unsigned char* preloc,
6987     const Sized_symbol<size>* gsym,
6988     const Symbol_value<size>* psymval,
6989     unsigned char* view,
6990     typename elfcpp::Elf_types<size>::Elf_Addr address,
6991     section_size_type /* view_size */)
6992 {
6993   if (view == NULL)
6994     return true;
6995
6996   typedef AArch64_relocate_functions<size, big_endian> Reloc;
6997
6998   const elfcpp::Rela<size, big_endian> rela(preloc);
6999   unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
7000   const AArch64_reloc_property* reloc_property =
7001       aarch64_reloc_property_table->get_reloc_property(r_type);
7002
7003   if (reloc_property == NULL)
7004     {
7005       std::string reloc_name =
7006           aarch64_reloc_property_table->reloc_name_in_error_message(r_type);
7007       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7008                              _("cannot relocate %s in object file"),
7009                              reloc_name.c_str());
7010       return true;
7011     }
7012
7013   const Sized_relobj_file<size, big_endian>* object = relinfo->object;
7014
7015   // Pick the value to use for symbols defined in the PLT.
7016   Symbol_value<size> symval;
7017   if (gsym != NULL
7018       && gsym->use_plt_offset(reloc_property->reference_flags()))
7019     {
7020       symval.set_output_value(target->plt_address_for_global(gsym));
7021       psymval = &symval;
7022     }
7023   else if (gsym == NULL && psymval->is_ifunc_symbol())
7024     {
7025       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7026       if (object->local_has_plt_offset(r_sym))
7027         {
7028           symval.set_output_value(target->plt_address_for_local(object, r_sym));
7029           psymval = &symval;
7030         }
7031     }
7032
7033   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7034
7035   // Get the GOT offset if needed.
7036   // For aarch64, the GOT pointer points to the start of the GOT section.
7037   bool have_got_offset = false;
7038   int got_offset = 0;
7039   int got_base = (target->got_ != NULL
7040                   ? (target->got_->current_data_size() >= 0x8000
7041                      ? 0x8000 : 0)
7042                   : 0);
7043   switch (r_type)
7044     {
7045     case elfcpp::R_AARCH64_MOVW_GOTOFF_G0:
7046     case elfcpp::R_AARCH64_MOVW_GOTOFF_G0_NC:
7047     case elfcpp::R_AARCH64_MOVW_GOTOFF_G1:
7048     case elfcpp::R_AARCH64_MOVW_GOTOFF_G1_NC:
7049     case elfcpp::R_AARCH64_MOVW_GOTOFF_G2:
7050     case elfcpp::R_AARCH64_MOVW_GOTOFF_G2_NC:
7051     case elfcpp::R_AARCH64_MOVW_GOTOFF_G3:
7052     case elfcpp::R_AARCH64_GOTREL64:
7053     case elfcpp::R_AARCH64_GOTREL32:
7054     case elfcpp::R_AARCH64_GOT_LD_PREL19:
7055     case elfcpp::R_AARCH64_LD64_GOTOFF_LO15:
7056     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
7057     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
7058     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
7059       if (gsym != NULL)
7060         {
7061           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
7062           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - got_base;
7063         }
7064       else
7065         {
7066           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7067           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
7068           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
7069                         - got_base);
7070         }
7071       have_got_offset = true;
7072       break;
7073
7074     default:
7075       break;
7076     }
7077
7078   typename Reloc::Status reloc_status = Reloc::STATUS_OKAY;
7079   typename elfcpp::Elf_types<size>::Elf_Addr value;
7080   switch (r_type)
7081     {
7082     case elfcpp::R_AARCH64_NONE:
7083       break;
7084
7085     case elfcpp::R_AARCH64_ABS64:
7086       if (!parameters->options().apply_dynamic_relocs()
7087           && parameters->options().output_is_position_independent()
7088           && gsym != NULL
7089           && gsym->needs_dynamic_reloc(reloc_property->reference_flags())
7090           && !gsym->can_use_relative_reloc(false))
7091         // We have generated an absolute dynamic relocation, so do not
7092         // apply the relocation statically. (Works around bugs in older
7093         // Android dynamic linkers.)
7094         break;
7095       reloc_status = Reloc::template rela_ua<64>(
7096         view, object, psymval, addend, reloc_property);
7097       break;
7098
7099     case elfcpp::R_AARCH64_ABS32:
7100       if (!parameters->options().apply_dynamic_relocs()
7101           && parameters->options().output_is_position_independent()
7102           && gsym != NULL
7103           && gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
7104         // We have generated an absolute dynamic relocation, so do not
7105         // apply the relocation statically. (Works around bugs in older
7106         // Android dynamic linkers.)
7107         break;
7108       reloc_status = Reloc::template rela_ua<32>(
7109         view, object, psymval, addend, reloc_property);
7110       break;
7111
7112     case elfcpp::R_AARCH64_ABS16:
7113       if (!parameters->options().apply_dynamic_relocs()
7114           && parameters->options().output_is_position_independent()
7115           && gsym != NULL
7116           && gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
7117         // We have generated an absolute dynamic relocation, so do not
7118         // apply the relocation statically. (Works around bugs in older
7119         // Android dynamic linkers.)
7120         break;
7121       reloc_status = Reloc::template rela_ua<16>(
7122         view, object, psymval, addend, reloc_property);
7123       break;
7124
7125     case elfcpp::R_AARCH64_PREL64:
7126       reloc_status = Reloc::template pcrela_ua<64>(
7127         view, object, psymval, addend, address, reloc_property);
7128       break;
7129
7130     case elfcpp::R_AARCH64_PREL32:
7131       reloc_status = Reloc::template pcrela_ua<32>(
7132         view, object, psymval, addend, address, reloc_property);
7133       break;
7134
7135     case elfcpp::R_AARCH64_PREL16:
7136       reloc_status = Reloc::template pcrela_ua<16>(
7137         view, object, psymval, addend, address, reloc_property);
7138       break;
7139
7140     case elfcpp::R_AARCH64_MOVW_UABS_G0:
7141     case elfcpp::R_AARCH64_MOVW_UABS_G0_NC:
7142     case elfcpp::R_AARCH64_MOVW_UABS_G1:
7143     case elfcpp::R_AARCH64_MOVW_UABS_G1_NC:
7144     case elfcpp::R_AARCH64_MOVW_UABS_G2:
7145     case elfcpp::R_AARCH64_MOVW_UABS_G2_NC:
7146     case elfcpp::R_AARCH64_MOVW_UABS_G3:
7147       reloc_status = Reloc::template rela_general<32>(
7148         view, object, psymval, addend, reloc_property);
7149       break;
7150     case elfcpp::R_AARCH64_MOVW_SABS_G0:
7151     case elfcpp::R_AARCH64_MOVW_SABS_G1:
7152     case elfcpp::R_AARCH64_MOVW_SABS_G2:
7153       reloc_status = Reloc::movnz(view, psymval->value(object, addend),
7154                                   reloc_property);
7155       break;
7156
7157     case elfcpp::R_AARCH64_LD_PREL_LO19:
7158       reloc_status = Reloc::template pcrela_general<32>(
7159           view, object, psymval, addend, address, reloc_property);
7160       break;
7161
7162     case elfcpp::R_AARCH64_ADR_PREL_LO21:
7163       reloc_status = Reloc::adr(view, object, psymval, addend,
7164                                 address, reloc_property);
7165       break;
7166
7167     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
7168     case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
7169       reloc_status = Reloc::adrp(view, object, psymval, addend, address,
7170                                  reloc_property);
7171       break;
7172
7173     case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:
7174     case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:
7175     case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:
7176     case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:
7177     case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC:
7178     case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
7179       reloc_status = Reloc::template rela_general<32>(
7180         view, object, psymval, addend, reloc_property);
7181       break;
7182
7183     case elfcpp::R_AARCH64_CALL26:
7184       if (this->skip_call_tls_get_addr_)
7185         {
7186           // Double check that the TLSGD insn has been optimized away.
7187           typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7188           Insntype insn = elfcpp::Swap<32, big_endian>::readval(
7189               reinterpret_cast<Insntype*>(view));
7190           gold_assert((insn & 0xff000000) == 0x91000000);
7191
7192           reloc_status = Reloc::STATUS_OKAY;
7193           this->skip_call_tls_get_addr_ = false;
7194           // Return false to stop further processing this reloc.
7195           return false;
7196         }
7197       // Fall through.
7198     case elfcpp::R_AARCH64_JUMP26:
7199       if (Reloc::maybe_apply_stub(r_type, relinfo, rela, view, address,
7200                                   gsym, psymval, object,
7201                                   target->stub_group_size_))
7202         break;
7203       // Fall through.
7204     case elfcpp::R_AARCH64_TSTBR14:
7205     case elfcpp::R_AARCH64_CONDBR19:
7206       reloc_status = Reloc::template pcrela_general<32>(
7207         view, object, psymval, addend, address, reloc_property);
7208       break;
7209
7210     case elfcpp::R_AARCH64_ADR_GOT_PAGE:
7211       gold_assert(have_got_offset);
7212       value = target->got_->address() + got_base + got_offset;
7213       reloc_status = Reloc::adrp(view, value + addend, address);
7214       break;
7215
7216     case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
7217       gold_assert(have_got_offset);
7218       value = target->got_->address() + got_base + got_offset;
7219       reloc_status = Reloc::template rela_general<32>(
7220         view, value, addend, reloc_property);
7221       break;
7222
7223     case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
7224       {
7225         gold_assert(have_got_offset);
7226         value = target->got_->address() + got_base + got_offset + addend -
7227           Reloc::Page(target->got_->address() + got_base);
7228         if ((value & 7) != 0)
7229           reloc_status = Reloc::STATUS_OVERFLOW;
7230         else
7231           reloc_status = Reloc::template reloc_common<32>(
7232             view, value, reloc_property);
7233         break;
7234       }
7235
7236     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7237     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
7238     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7239     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
7240     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7241     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7242     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7243     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
7244     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7245     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
7246     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7247     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7248     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
7249     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7250     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
7251     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
7252     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
7253     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
7254     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7255     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7256     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7257     case elfcpp::R_AARCH64_TLSDESC_CALL:
7258       reloc_status = relocate_tls(relinfo, target, relnum, rela, r_type,
7259                                   gsym, psymval, view, address);
7260       break;
7261
7262     // These are dynamic relocations, which are unexpected when linking.
7263     case elfcpp::R_AARCH64_COPY:
7264     case elfcpp::R_AARCH64_GLOB_DAT:
7265     case elfcpp::R_AARCH64_JUMP_SLOT:
7266     case elfcpp::R_AARCH64_RELATIVE:
7267     case elfcpp::R_AARCH64_IRELATIVE:
7268     case elfcpp::R_AARCH64_TLS_DTPREL64:
7269     case elfcpp::R_AARCH64_TLS_DTPMOD64:
7270     case elfcpp::R_AARCH64_TLS_TPREL64:
7271     case elfcpp::R_AARCH64_TLSDESC:
7272       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7273                              _("unexpected reloc %u in object file"),
7274                              r_type);
7275       break;
7276
7277     default:
7278       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7279                              _("unsupported reloc %s"),
7280                              reloc_property->name().c_str());
7281       break;
7282     }
7283
7284   // Report any errors.
7285   switch (reloc_status)
7286     {
7287     case Reloc::STATUS_OKAY:
7288       break;
7289     case Reloc::STATUS_OVERFLOW:
7290       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7291                              _("relocation overflow in %s"),
7292                              reloc_property->name().c_str());
7293       break;
7294     case Reloc::STATUS_BAD_RELOC:
7295       gold_error_at_location(
7296           relinfo,
7297           relnum,
7298           rela.get_r_offset(),
7299           _("unexpected opcode while processing relocation %s"),
7300           reloc_property->name().c_str());
7301       break;
7302     default:
7303       gold_unreachable();
7304     }
7305
7306   return true;
7307 }
7308
7309
7310 template<int size, bool big_endian>
7311 inline
7312 typename AArch64_relocate_functions<size, big_endian>::Status
7313 Target_aarch64<size, big_endian>::Relocate::relocate_tls(
7314     const Relocate_info<size, big_endian>* relinfo,
7315     Target_aarch64<size, big_endian>* target,
7316     size_t relnum,
7317     const elfcpp::Rela<size, big_endian>& rela,
7318     unsigned int r_type, const Sized_symbol<size>* gsym,
7319     const Symbol_value<size>* psymval,
7320     unsigned char* view,
7321     typename elfcpp::Elf_types<size>::Elf_Addr address)
7322 {
7323   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7324   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7325
7326   Output_segment* tls_segment = relinfo->layout->tls_segment();
7327   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7328   const AArch64_reloc_property* reloc_property =
7329       aarch64_reloc_property_table->get_reloc_property(r_type);
7330   gold_assert(reloc_property != NULL);
7331
7332   const bool is_final = (gsym == NULL
7333                          ? !parameters->options().shared()
7334                          : gsym->final_value_is_known());
7335   tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
7336       optimize_tls_reloc(is_final, r_type);
7337
7338   Sized_relobj_file<size, big_endian>* object = relinfo->object;
7339   int tls_got_offset_type;
7340   switch (r_type)
7341     {
7342     case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7343     case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:  // Global-dynamic
7344       {
7345         if (tlsopt == tls::TLSOPT_TO_LE)
7346           {
7347             if (tls_segment == NULL)
7348               {
7349                 gold_assert(parameters->errors()->error_count() > 0
7350                             || issue_undefined_symbol_error(gsym));
7351                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7352               }
7353             return tls_gd_to_le(relinfo, target, rela, r_type, view,
7354                                 psymval);
7355           }
7356         else if (tlsopt == tls::TLSOPT_NONE)
7357           {
7358             tls_got_offset_type = GOT_TYPE_TLS_PAIR;
7359             // Firstly get the address for the got entry.
7360             typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7361             if (gsym != NULL)
7362               {
7363                 gold_assert(gsym->has_got_offset(tls_got_offset_type));
7364                 got_entry_address = target->got_->address() +
7365                                     gsym->got_offset(tls_got_offset_type);
7366               }
7367             else
7368               {
7369                 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7370                 gold_assert(
7371                   object->local_has_got_offset(r_sym, tls_got_offset_type));
7372                 got_entry_address = target->got_->address() +
7373                   object->local_got_offset(r_sym, tls_got_offset_type);
7374               }
7375
7376             // Relocate the address into adrp/ld, adrp/add pair.
7377             switch (r_type)
7378               {
7379               case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
7380                 return aarch64_reloc_funcs::adrp(
7381                   view, got_entry_address + addend, address);
7382
7383                 break;
7384
7385               case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
7386                 return aarch64_reloc_funcs::template rela_general<32>(
7387                   view, got_entry_address, addend, reloc_property);
7388                 break;
7389
7390               default:
7391                 gold_unreachable();
7392               }
7393           }
7394         gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
7395                                _("unsupported gd_to_ie relaxation on %u"),
7396                                r_type);
7397       }
7398       break;
7399
7400     case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7401     case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:  // Local-dynamic
7402       {
7403         if (tlsopt == tls::TLSOPT_TO_LE)
7404           {
7405             if (tls_segment == NULL)
7406               {
7407                 gold_assert(parameters->errors()->error_count() > 0
7408                             || issue_undefined_symbol_error(gsym));
7409                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7410               }
7411             return this->tls_ld_to_le(relinfo, target, rela, r_type, view,
7412                                       psymval);
7413           }
7414
7415         gold_assert(tlsopt == tls::TLSOPT_NONE);
7416         // Relocate the field with the offset of the GOT entry for
7417         // the module index.
7418         typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7419         got_entry_address = (target->got_mod_index_entry(NULL, NULL, NULL) +
7420                              target->got_->address());
7421
7422         switch (r_type)
7423           {
7424           case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
7425             return aarch64_reloc_funcs::adrp(
7426               view, got_entry_address + addend, address);
7427             break;
7428
7429           case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
7430             return aarch64_reloc_funcs::template rela_general<32>(
7431               view, got_entry_address, addend, reloc_property);
7432             break;
7433
7434           default:
7435             gold_unreachable();
7436           }
7437       }
7438       break;
7439
7440     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7441     case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7442     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7443     case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:  // Other local-dynamic
7444       {
7445         AArch64_address value = psymval->value(object, 0);
7446         if (tlsopt == tls::TLSOPT_TO_LE)
7447           {
7448             if (tls_segment == NULL)
7449               {
7450                 gold_assert(parameters->errors()->error_count() > 0
7451                             || issue_undefined_symbol_error(gsym));
7452                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7453               }
7454           }
7455         switch (r_type)
7456           {
7457           case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
7458             return aarch64_reloc_funcs::movnz(view, value + addend,
7459                                               reloc_property);
7460             break;
7461
7462           case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
7463           case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
7464           case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
7465             return aarch64_reloc_funcs::template rela_general<32>(
7466                 view, value, addend, reloc_property);
7467             break;
7468
7469           default:
7470             gold_unreachable();
7471           }
7472         // We should never reach here.
7473       }
7474       break;
7475
7476     case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7477     case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:  // Initial-exec
7478       {
7479         if (tlsopt == tls::TLSOPT_TO_LE)
7480           {
7481             if (tls_segment == NULL)
7482               {
7483                 gold_assert(parameters->errors()->error_count() > 0
7484                             || issue_undefined_symbol_error(gsym));
7485                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7486               }
7487             return tls_ie_to_le(relinfo, target, rela, r_type, view,
7488                                 psymval);
7489           }
7490         tls_got_offset_type = GOT_TYPE_TLS_OFFSET;
7491
7492         // Firstly get the address for the got entry.
7493         typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7494         if (gsym != NULL)
7495           {
7496             gold_assert(gsym->has_got_offset(tls_got_offset_type));
7497             got_entry_address = target->got_->address() +
7498                                 gsym->got_offset(tls_got_offset_type);
7499           }
7500         else
7501           {
7502             unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7503             gold_assert(
7504                 object->local_has_got_offset(r_sym, tls_got_offset_type));
7505             got_entry_address = target->got_->address() +
7506                 object->local_got_offset(r_sym, tls_got_offset_type);
7507           }
7508         // Relocate the address into adrp/ld, adrp/add pair.
7509         switch (r_type)
7510           {
7511           case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
7512             return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
7513                                              address);
7514             break;
7515           case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
7516             return aarch64_reloc_funcs::template rela_general<32>(
7517               view, got_entry_address, addend, reloc_property);
7518           default:
7519             gold_unreachable();
7520           }
7521       }
7522       // We shall never reach here.
7523       break;
7524
7525     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7526     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7527     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
7528     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7529     case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
7530     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
7531     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
7532     case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
7533       {
7534         gold_assert(tls_segment != NULL);
7535         AArch64_address value = psymval->value(object, 0);
7536
7537         if (!parameters->options().shared())
7538           {
7539             AArch64_address aligned_tcb_size =
7540                 align_address(target->tcb_size(),
7541                               tls_segment->maximum_alignment());
7542             value += aligned_tcb_size;
7543             switch (r_type)
7544               {
7545               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
7546               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
7547               case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
7548                 return aarch64_reloc_funcs::movnz(view, value + addend,
7549                                                   reloc_property);
7550               default:
7551                 return aarch64_reloc_funcs::template
7552                   rela_general<32>(view,
7553                                    value,
7554                                    addend,
7555                                    reloc_property);
7556               }
7557           }
7558         else
7559           gold_error(_("%s: unsupported reloc %u "
7560                        "in non-static TLSLE mode."),
7561                      object->name().c_str(), r_type);
7562       }
7563       break;
7564
7565     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7566     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7567     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7568     case elfcpp::R_AARCH64_TLSDESC_CALL:
7569       {
7570         if (tlsopt == tls::TLSOPT_TO_LE)
7571           {
7572             if (tls_segment == NULL)
7573               {
7574                 gold_assert(parameters->errors()->error_count() > 0
7575                             || issue_undefined_symbol_error(gsym));
7576                 return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7577               }
7578             return tls_desc_gd_to_le(relinfo, target, rela, r_type,
7579                                      view, psymval);
7580           }
7581         else
7582           {
7583             tls_got_offset_type = (tlsopt == tls::TLSOPT_TO_IE
7584                                    ? GOT_TYPE_TLS_OFFSET
7585                                    : GOT_TYPE_TLS_DESC);
7586             int got_tlsdesc_offset = 0;
7587             if (r_type != elfcpp::R_AARCH64_TLSDESC_CALL
7588                 && tlsopt == tls::TLSOPT_NONE)
7589               {
7590                 // We created GOT entries in the .got.tlsdesc portion of the
7591                 // .got.plt section, but the offset stored in the symbol is the
7592                 // offset within .got.tlsdesc.
7593                 got_tlsdesc_offset = (target->got_tlsdesc_->address()
7594                                       - target->got_->address());
7595               }
7596             typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
7597             if (gsym != NULL)
7598               {
7599                 gold_assert(gsym->has_got_offset(tls_got_offset_type));
7600                 got_entry_address = target->got_->address()
7601                                     + got_tlsdesc_offset
7602                                     + gsym->got_offset(tls_got_offset_type);
7603               }
7604             else
7605               {
7606                 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
7607                 gold_assert(
7608                     object->local_has_got_offset(r_sym, tls_got_offset_type));
7609                 got_entry_address = target->got_->address() +
7610                   got_tlsdesc_offset +
7611                   object->local_got_offset(r_sym, tls_got_offset_type);
7612               }
7613             if (tlsopt == tls::TLSOPT_TO_IE)
7614               {
7615                 return tls_desc_gd_to_ie(relinfo, target, rela, r_type,
7616                                          view, psymval, got_entry_address,
7617                                          address);
7618               }
7619
7620             // Now do tlsdesc relocation.
7621             switch (r_type)
7622               {
7623               case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7624                 return aarch64_reloc_funcs::adrp(view,
7625                                                  got_entry_address + addend,
7626                                                  address);
7627                 break;
7628               case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7629               case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7630                 return aarch64_reloc_funcs::template rela_general<32>(
7631                   view, got_entry_address, addend, reloc_property);
7632                 break;
7633               case elfcpp::R_AARCH64_TLSDESC_CALL:
7634                 return aarch64_reloc_funcs::STATUS_OKAY;
7635                 break;
7636               default:
7637                 gold_unreachable();
7638               }
7639           }
7640         }
7641       break;
7642
7643     default:
7644       gold_error(_("%s: unsupported TLS reloc %u."),
7645                  object->name().c_str(), r_type);
7646     }
7647   return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7648 }  // End of relocate_tls.
7649
7650
7651 template<int size, bool big_endian>
7652 inline
7653 typename AArch64_relocate_functions<size, big_endian>::Status
7654 Target_aarch64<size, big_endian>::Relocate::tls_gd_to_le(
7655              const Relocate_info<size, big_endian>* relinfo,
7656              Target_aarch64<size, big_endian>* target,
7657              const elfcpp::Rela<size, big_endian>& rela,
7658              unsigned int r_type,
7659              unsigned char* view,
7660              const Symbol_value<size>* psymval)
7661 {
7662   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7663   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7664   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7665
7666   Insntype* ip = reinterpret_cast<Insntype*>(view);
7667   Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
7668   Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
7669   Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
7670
7671   if (r_type == elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC)
7672     {
7673       // This is the 2nd relocs, optimization should already have been
7674       // done.
7675       gold_assert((insn1 & 0xfff00000) == 0x91400000);
7676       return aarch64_reloc_funcs::STATUS_OKAY;
7677     }
7678
7679   // The original sequence is -
7680   //   90000000        adrp    x0, 0 <main>
7681   //   91000000        add     x0, x0, #0x0
7682   //   94000000        bl      0 <__tls_get_addr>
7683   // optimized to sequence -
7684   //   d53bd040        mrs     x0, tpidr_el0
7685   //   91400000        add     x0, x0, #0x0, lsl #12
7686   //   91000000        add     x0, x0, #0x0
7687
7688   // Unlike tls_ie_to_le, we change the 3 insns in one function call when we
7689   // encounter the first relocation "R_AARCH64_TLSGD_ADR_PAGE21". Because we
7690   // have to change "bl tls_get_addr", which does not have a corresponding tls
7691   // relocation type. So before proceeding, we need to make sure compiler
7692   // does not change the sequence.
7693   if(!(insn1 == 0x90000000      // adrp x0,0
7694        && insn2 == 0x91000000   // add x0, x0, #0x0
7695        && insn3 == 0x94000000)) // bl 0
7696     {
7697       // Ideally we should give up gd_to_le relaxation and do gd access.
7698       // However the gd_to_le relaxation decision has been made early
7699       // in the scan stage, where we did not allocate any GOT entry for
7700       // this symbol. Therefore we have to exit and report error now.
7701       gold_error(_("unexpected reloc insn sequence while relaxing "
7702                    "tls gd to le for reloc %u."), r_type);
7703       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7704     }
7705
7706   // Write new insns.
7707   insn1 = 0xd53bd040;  // mrs x0, tpidr_el0
7708   insn2 = 0x91400000;  // add x0, x0, #0x0, lsl #12
7709   insn3 = 0x91000000;  // add x0, x0, #0x0
7710   elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
7711   elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
7712   elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
7713
7714   // Calculate tprel value.
7715   Output_segment* tls_segment = relinfo->layout->tls_segment();
7716   gold_assert(tls_segment != NULL);
7717   AArch64_address value = psymval->value(relinfo->object, 0);
7718   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7719   AArch64_address aligned_tcb_size =
7720       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7721   AArch64_address x = value + aligned_tcb_size;
7722
7723   // After new insns are written, apply TLSLE relocs.
7724   const AArch64_reloc_property* rp1 =
7725       aarch64_reloc_property_table->get_reloc_property(
7726           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
7727   const AArch64_reloc_property* rp2 =
7728       aarch64_reloc_property_table->get_reloc_property(
7729           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
7730   gold_assert(rp1 != NULL && rp2 != NULL);
7731
7732   typename aarch64_reloc_funcs::Status s1 =
7733       aarch64_reloc_funcs::template rela_general<32>(view + 4,
7734                                                      x,
7735                                                      addend,
7736                                                      rp1);
7737   if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
7738     return s1;
7739
7740   typename aarch64_reloc_funcs::Status s2 =
7741       aarch64_reloc_funcs::template rela_general<32>(view + 8,
7742                                                      x,
7743                                                      addend,
7744                                                      rp2);
7745
7746   this->skip_call_tls_get_addr_ = true;
7747   return s2;
7748 }  // End of tls_gd_to_le
7749
7750
7751 template<int size, bool big_endian>
7752 inline
7753 typename AArch64_relocate_functions<size, big_endian>::Status
7754 Target_aarch64<size, big_endian>::Relocate::tls_ld_to_le(
7755              const Relocate_info<size, big_endian>* relinfo,
7756              Target_aarch64<size, big_endian>* target,
7757              const elfcpp::Rela<size, big_endian>& rela,
7758              unsigned int r_type,
7759              unsigned char* view,
7760              const Symbol_value<size>* psymval)
7761 {
7762   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7763   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7764   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7765
7766   Insntype* ip = reinterpret_cast<Insntype*>(view);
7767   Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
7768   Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
7769   Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
7770
7771   if (r_type == elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC)
7772     {
7773       // This is the 2nd relocs, optimization should already have been
7774       // done.
7775       gold_assert((insn1 & 0xfff00000) == 0x91400000);
7776       return aarch64_reloc_funcs::STATUS_OKAY;
7777     }
7778
7779   // The original sequence is -
7780   //   90000000        adrp    x0, 0 <main>
7781   //   91000000        add     x0, x0, #0x0
7782   //   94000000        bl      0 <__tls_get_addr>
7783   // optimized to sequence -
7784   //   d53bd040        mrs     x0, tpidr_el0
7785   //   91400000        add     x0, x0, #0x0, lsl #12
7786   //   91000000        add     x0, x0, #0x0
7787
7788   // Unlike tls_ie_to_le, we change the 3 insns in one function call when we
7789   // encounter the first relocation "R_AARCH64_TLSLD_ADR_PAGE21". Because we
7790   // have to change "bl tls_get_addr", which does not have a corresponding tls
7791   // relocation type. So before proceeding, we need to make sure compiler
7792   // does not change the sequence.
7793   if(!(insn1 == 0x90000000      // adrp x0,0
7794        && insn2 == 0x91000000   // add x0, x0, #0x0
7795        && insn3 == 0x94000000)) // bl 0
7796     {
7797       // Ideally we should give up gd_to_le relaxation and do gd access.
7798       // However the gd_to_le relaxation decision has been made early
7799       // in the scan stage, where we did not allocate a GOT entry for
7800       // this symbol. Therefore we have to exit and report an error now.
7801       gold_error(_("unexpected reloc insn sequence while relaxing "
7802                    "tls gd to le for reloc %u."), r_type);
7803       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7804     }
7805
7806   // Write new insns.
7807   insn1 = 0xd53bd040;  // mrs x0, tpidr_el0
7808   insn2 = 0x91400000;  // add x0, x0, #0x0, lsl #12
7809   insn3 = 0x91000000;  // add x0, x0, #0x0
7810   elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
7811   elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
7812   elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
7813
7814   // Calculate tprel value.
7815   Output_segment* tls_segment = relinfo->layout->tls_segment();
7816   gold_assert(tls_segment != NULL);
7817   AArch64_address value = psymval->value(relinfo->object, 0);
7818   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7819   AArch64_address aligned_tcb_size =
7820       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7821   AArch64_address x = value + aligned_tcb_size;
7822
7823   // After new insns are written, apply TLSLE relocs.
7824   const AArch64_reloc_property* rp1 =
7825       aarch64_reloc_property_table->get_reloc_property(
7826           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
7827   const AArch64_reloc_property* rp2 =
7828       aarch64_reloc_property_table->get_reloc_property(
7829           elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
7830   gold_assert(rp1 != NULL && rp2 != NULL);
7831
7832   typename aarch64_reloc_funcs::Status s1 =
7833       aarch64_reloc_funcs::template rela_general<32>(view + 4,
7834                                                      x,
7835                                                      addend,
7836                                                      rp1);
7837   if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
7838     return s1;
7839
7840   typename aarch64_reloc_funcs::Status s2 =
7841       aarch64_reloc_funcs::template rela_general<32>(view + 8,
7842                                                      x,
7843                                                      addend,
7844                                                      rp2);
7845
7846   this->skip_call_tls_get_addr_ = true;
7847   return s2;
7848
7849 }  // End of tls_ld_to_le
7850
7851 template<int size, bool big_endian>
7852 inline
7853 typename AArch64_relocate_functions<size, big_endian>::Status
7854 Target_aarch64<size, big_endian>::Relocate::tls_ie_to_le(
7855              const Relocate_info<size, big_endian>* relinfo,
7856              Target_aarch64<size, big_endian>* target,
7857              const elfcpp::Rela<size, big_endian>& rela,
7858              unsigned int r_type,
7859              unsigned char* view,
7860              const Symbol_value<size>* psymval)
7861 {
7862   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7863   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7864   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7865
7866   AArch64_address value = psymval->value(relinfo->object, 0);
7867   Output_segment* tls_segment = relinfo->layout->tls_segment();
7868   AArch64_address aligned_tcb_address =
7869       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7870   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7871   AArch64_address x = value + addend + aligned_tcb_address;
7872   // "x" is the offset to tp, we can only do this if x is within
7873   // range [0, 2^32-1]
7874   if (!(size == 32 || (size == 64 && (static_cast<uint64_t>(x) >> 32) == 0)))
7875     {
7876       gold_error(_("TLS variable referred by reloc %u is too far from TP."),
7877                  r_type);
7878       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7879     }
7880
7881   Insntype* ip = reinterpret_cast<Insntype*>(view);
7882   Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
7883   unsigned int regno;
7884   Insntype newinsn;
7885   if (r_type == elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21)
7886     {
7887       // Generate movz.
7888       regno = (insn & 0x1f);
7889       newinsn = (0xd2a00000 | regno) | (((x >> 16) & 0xffff) << 5);
7890     }
7891   else if (r_type == elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC)
7892     {
7893       // Generate movk.
7894       regno = (insn & 0x1f);
7895       gold_assert(regno == ((insn >> 5) & 0x1f));
7896       newinsn = (0xf2800000 | regno) | ((x & 0xffff) << 5);
7897     }
7898   else
7899     gold_unreachable();
7900
7901   elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
7902   return aarch64_reloc_funcs::STATUS_OKAY;
7903 }  // End of tls_ie_to_le
7904
7905
7906 template<int size, bool big_endian>
7907 inline
7908 typename AArch64_relocate_functions<size, big_endian>::Status
7909 Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_le(
7910              const Relocate_info<size, big_endian>* relinfo,
7911              Target_aarch64<size, big_endian>* target,
7912              const elfcpp::Rela<size, big_endian>& rela,
7913              unsigned int r_type,
7914              unsigned char* view,
7915              const Symbol_value<size>* psymval)
7916 {
7917   typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
7918   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7919   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7920
7921   // TLSDESC-GD sequence is like:
7922   //   adrp  x0, :tlsdesc:v1
7923   //   ldr   x1, [x0, #:tlsdesc_lo12:v1]
7924   //   add   x0, x0, :tlsdesc_lo12:v1
7925   //   .tlsdesccall    v1
7926   //   blr   x1
7927   // After desc_gd_to_le optimization, the sequence will be like:
7928   //   movz  x0, #0x0, lsl #16
7929   //   movk  x0, #0x10
7930   //   nop
7931   //   nop
7932
7933   // Calculate tprel value.
7934   Output_segment* tls_segment = relinfo->layout->tls_segment();
7935   gold_assert(tls_segment != NULL);
7936   Insntype* ip = reinterpret_cast<Insntype*>(view);
7937   const elfcpp::Elf_Xword addend = rela.get_r_addend();
7938   AArch64_address value = psymval->value(relinfo->object, addend);
7939   AArch64_address aligned_tcb_size =
7940       align_address(target->tcb_size(), tls_segment->maximum_alignment());
7941   AArch64_address x = value + aligned_tcb_size;
7942   // x is the offset to tp, we can only do this if x is within range
7943   // [0, 2^32-1]. If x is out of range, fail and exit.
7944   if (size == 64 && (static_cast<uint64_t>(x) >> 32) != 0)
7945     {
7946       gold_error(_("TLS variable referred by reloc %u is too far from TP. "
7947                    "We Can't do gd_to_le relaxation.\n"), r_type);
7948       return aarch64_reloc_funcs::STATUS_BAD_RELOC;
7949     }
7950   Insntype newinsn;
7951   switch (r_type)
7952     {
7953     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
7954     case elfcpp::R_AARCH64_TLSDESC_CALL:
7955       // Change to nop
7956       newinsn = 0xd503201f;
7957       break;
7958
7959     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
7960       // Change to movz.
7961       newinsn = 0xd2a00000 | (((x >> 16) & 0xffff) << 5);
7962       break;
7963
7964     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
7965       // Change to movk.
7966       newinsn = 0xf2800000 | ((x & 0xffff) << 5);
7967       break;
7968
7969     default:
7970       gold_error(_("unsupported tlsdesc gd_to_le optimization on reloc %u"),
7971                  r_type);
7972       gold_unreachable();
7973     }
7974   elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
7975   return aarch64_reloc_funcs::STATUS_OKAY;
7976 }  // End of tls_desc_gd_to_le
7977
7978
7979 template<int size, bool big_endian>
7980 inline
7981 typename AArch64_relocate_functions<size, big_endian>::Status
7982 Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_ie(
7983              const Relocate_info<size, big_endian>* /* relinfo */,
7984              Target_aarch64<size, big_endian>* /* target */,
7985              const elfcpp::Rela<size, big_endian>& rela,
7986              unsigned int r_type,
7987              unsigned char* view,
7988              const Symbol_value<size>* /* psymval */,
7989              typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address,
7990              typename elfcpp::Elf_types<size>::Elf_Addr address)
7991 {
7992   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
7993   typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
7994
7995   // TLSDESC-GD sequence is like:
7996   //   adrp  x0, :tlsdesc:v1
7997   //   ldr   x1, [x0, #:tlsdesc_lo12:v1]
7998   //   add   x0, x0, :tlsdesc_lo12:v1
7999   //   .tlsdesccall    v1
8000   //   blr   x1
8001   // After desc_gd_to_ie optimization, the sequence will be like:
8002   //   adrp  x0, :tlsie:v1
8003   //   ldr   x0, [x0, :tlsie_lo12:v1]
8004   //   nop
8005   //   nop
8006
8007   Insntype* ip = reinterpret_cast<Insntype*>(view);
8008   const elfcpp::Elf_Xword addend = rela.get_r_addend();
8009   Insntype newinsn;
8010   switch (r_type)
8011     {
8012     case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
8013     case elfcpp::R_AARCH64_TLSDESC_CALL:
8014       // Change to nop
8015       newinsn = 0xd503201f;
8016       elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
8017       break;
8018
8019     case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
8020       {
8021         return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
8022                                          address);
8023       }
8024       break;
8025
8026     case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
8027       {
8028        // Set ldr target register to be x0.
8029        Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
8030        insn &= 0xffffffe0;
8031        elfcpp::Swap<32, big_endian>::writeval(ip, insn);
8032        // Do relocation.
8033         const AArch64_reloc_property* reloc_property =
8034             aarch64_reloc_property_table->get_reloc_property(
8035               elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC);
8036         return aarch64_reloc_funcs::template rela_general<32>(
8037                  view, got_entry_address, addend, reloc_property);
8038       }
8039       break;
8040
8041     default:
8042       gold_error(_("Don't support tlsdesc gd_to_ie optimization on reloc %u"),
8043                  r_type);
8044       gold_unreachable();
8045     }
8046   return aarch64_reloc_funcs::STATUS_OKAY;
8047 }  // End of tls_desc_gd_to_ie
8048
8049 // Relocate section data.
8050
8051 template<int size, bool big_endian>
8052 void
8053 Target_aarch64<size, big_endian>::relocate_section(
8054     const Relocate_info<size, big_endian>* relinfo,
8055     unsigned int sh_type,
8056     const unsigned char* prelocs,
8057     size_t reloc_count,
8058     Output_section* output_section,
8059     bool needs_special_offset_handling,
8060     unsigned char* view,
8061     typename elfcpp::Elf_types<size>::Elf_Addr address,
8062     section_size_type view_size,
8063     const Reloc_symbol_changes* reloc_symbol_changes)
8064 {
8065   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
8066   typedef Target_aarch64<size, big_endian> Aarch64;
8067   typedef typename Target_aarch64<size, big_endian>::Relocate AArch64_relocate;
8068   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8069       Classify_reloc;
8070
8071   gold_assert(sh_type == elfcpp::SHT_RELA);
8072
8073   // See if we are relocating a relaxed input section.  If so, the view
8074   // covers the whole output section and we need to adjust accordingly.
8075   if (needs_special_offset_handling)
8076     {
8077       const Output_relaxed_input_section* poris =
8078         output_section->find_relaxed_input_section(relinfo->object,
8079                                                    relinfo->data_shndx);
8080       if (poris != NULL)
8081         {
8082           Address section_address = poris->address();
8083           section_size_type section_size = poris->data_size();
8084
8085           gold_assert((section_address >= address)
8086                       && ((section_address + section_size)
8087                           <= (address + view_size)));
8088
8089           off_t offset = section_address - address;
8090           view += offset;
8091           address += offset;
8092           view_size = section_size;
8093         }
8094     }
8095
8096   gold::relocate_section<size, big_endian, Aarch64, AArch64_relocate,
8097                          gold::Default_comdat_behavior, Classify_reloc>(
8098     relinfo,
8099     this,
8100     prelocs,
8101     reloc_count,
8102     output_section,
8103     needs_special_offset_handling,
8104     view,
8105     address,
8106     view_size,
8107     reloc_symbol_changes);
8108 }
8109
8110 // Scan the relocs during a relocatable link.
8111
8112 template<int size, bool big_endian>
8113 void
8114 Target_aarch64<size, big_endian>::scan_relocatable_relocs(
8115     Symbol_table* symtab,
8116     Layout* layout,
8117     Sized_relobj_file<size, big_endian>* object,
8118     unsigned int data_shndx,
8119     unsigned int sh_type,
8120     const unsigned char* prelocs,
8121     size_t reloc_count,
8122     Output_section* output_section,
8123     bool needs_special_offset_handling,
8124     size_t local_symbol_count,
8125     const unsigned char* plocal_symbols,
8126     Relocatable_relocs* rr)
8127 {
8128   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8129       Classify_reloc;
8130   typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
8131       Scan_relocatable_relocs;
8132
8133   gold_assert(sh_type == elfcpp::SHT_RELA);
8134
8135   gold::scan_relocatable_relocs<size, big_endian, Scan_relocatable_relocs>(
8136     symtab,
8137     layout,
8138     object,
8139     data_shndx,
8140     prelocs,
8141     reloc_count,
8142     output_section,
8143     needs_special_offset_handling,
8144     local_symbol_count,
8145     plocal_symbols,
8146     rr);
8147 }
8148
8149 // Scan the relocs for --emit-relocs.
8150
8151 template<int size, bool big_endian>
8152 void
8153 Target_aarch64<size, big_endian>::emit_relocs_scan(
8154     Symbol_table* symtab,
8155     Layout* layout,
8156     Sized_relobj_file<size, big_endian>* object,
8157     unsigned int data_shndx,
8158     unsigned int sh_type,
8159     const unsigned char* prelocs,
8160     size_t reloc_count,
8161     Output_section* output_section,
8162     bool needs_special_offset_handling,
8163     size_t local_symbol_count,
8164     const unsigned char* plocal_syms,
8165     Relocatable_relocs* rr)
8166 {
8167   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8168       Classify_reloc;
8169   typedef gold::Default_emit_relocs_strategy<Classify_reloc>
8170       Emit_relocs_strategy;
8171
8172   gold_assert(sh_type == elfcpp::SHT_RELA);
8173
8174   gold::scan_relocatable_relocs<size, big_endian, Emit_relocs_strategy>(
8175     symtab,
8176     layout,
8177     object,
8178     data_shndx,
8179     prelocs,
8180     reloc_count,
8181     output_section,
8182     needs_special_offset_handling,
8183     local_symbol_count,
8184     plocal_syms,
8185     rr);
8186 }
8187
8188 // Relocate a section during a relocatable link.
8189
8190 template<int size, bool big_endian>
8191 void
8192 Target_aarch64<size, big_endian>::relocate_relocs(
8193     const Relocate_info<size, big_endian>* relinfo,
8194     unsigned int sh_type,
8195     const unsigned char* prelocs,
8196     size_t reloc_count,
8197     Output_section* output_section,
8198     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
8199     unsigned char* view,
8200     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
8201     section_size_type view_size,
8202     unsigned char* reloc_view,
8203     section_size_type reloc_view_size)
8204 {
8205   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, big_endian>
8206       Classify_reloc;
8207
8208   gold_assert(sh_type == elfcpp::SHT_RELA);
8209
8210   gold::relocate_relocs<size, big_endian, Classify_reloc>(
8211     relinfo,
8212     prelocs,
8213     reloc_count,
8214     output_section,
8215     offset_in_output_section,
8216     view,
8217     view_address,
8218     view_size,
8219     reloc_view,
8220     reloc_view_size);
8221 }
8222
8223
8224 // Return whether this is a 3-insn erratum sequence.
8225
8226 template<int size, bool big_endian>
8227 bool
8228 Target_aarch64<size, big_endian>::is_erratum_843419_sequence(
8229     typename elfcpp::Swap<32,big_endian>::Valtype insn1,
8230     typename elfcpp::Swap<32,big_endian>::Valtype insn2,
8231     typename elfcpp::Swap<32,big_endian>::Valtype insn3)
8232 {
8233   unsigned rt1, rt2;
8234   bool load, pair;
8235
8236   // The 2nd insn is a single register load or store; or register pair
8237   // store.
8238   if (Insn_utilities::aarch64_mem_op_p(insn2, &rt1, &rt2, &pair, &load)
8239       && (!pair || (pair && !load)))
8240     {
8241       // The 3rd insn is a load or store instruction from the "Load/store
8242       // register (unsigned immediate)" encoding class, using Rn as the
8243       // base address register.
8244       if (Insn_utilities::aarch64_ldst_uimm(insn3)
8245           && (Insn_utilities::aarch64_rn(insn3)
8246               == Insn_utilities::aarch64_rd(insn1)))
8247         return true;
8248     }
8249   return false;
8250 }
8251
8252
8253 // Return whether this is a 835769 sequence.
8254 // (Similarly implemented as in elfnn-aarch64.c.)
8255
8256 template<int size, bool big_endian>
8257 bool
8258 Target_aarch64<size, big_endian>::is_erratum_835769_sequence(
8259     typename elfcpp::Swap<32,big_endian>::Valtype insn1,
8260     typename elfcpp::Swap<32,big_endian>::Valtype insn2)
8261 {
8262   uint32_t rt;
8263   uint32_t rt2 = 0;
8264   uint32_t rn;
8265   uint32_t rm;
8266   uint32_t ra;
8267   bool pair;
8268   bool load;
8269
8270   if (Insn_utilities::aarch64_mlxl(insn2)
8271       && Insn_utilities::aarch64_mem_op_p (insn1, &rt, &rt2, &pair, &load))
8272     {
8273       /* Any SIMD memory op is independent of the subsequent MLA
8274          by definition of the erratum.  */
8275       if (Insn_utilities::aarch64_bit(insn1, 26))
8276         return true;
8277
8278       /* If not SIMD, check for integer memory ops and MLA relationship.  */
8279       rn = Insn_utilities::aarch64_rn(insn2);
8280       ra = Insn_utilities::aarch64_ra(insn2);
8281       rm = Insn_utilities::aarch64_rm(insn2);
8282
8283       /* If this is a load and there's a true(RAW) dependency, we are safe
8284          and this is not an erratum sequence.  */
8285       if (load &&
8286           (rt == rn || rt == rm || rt == ra
8287            || (pair && (rt2 == rn || rt2 == rm || rt2 == ra))))
8288         return false;
8289
8290       /* We conservatively put out stubs for all other cases (including
8291          writebacks).  */
8292       return true;
8293     }
8294
8295   return false;
8296 }
8297
8298
8299 // Helper method to create erratum stub for ST_E_843419 and ST_E_835769.
8300
8301 template<int size, bool big_endian>
8302 void
8303 Target_aarch64<size, big_endian>::create_erratum_stub(
8304     AArch64_relobj<size, big_endian>* relobj,
8305     unsigned int shndx,
8306     section_size_type erratum_insn_offset,
8307     Address erratum_address,
8308     typename Insn_utilities::Insntype erratum_insn,
8309     int erratum_type,
8310     unsigned int e843419_adrp_offset)
8311 {
8312   gold_assert(erratum_type == ST_E_843419 || erratum_type == ST_E_835769);
8313   The_stub_table* stub_table = relobj->stub_table(shndx);
8314   gold_assert(stub_table != NULL);
8315   if (stub_table->find_erratum_stub(relobj,
8316                                     shndx,
8317                                     erratum_insn_offset) == NULL)
8318     {
8319       const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
8320       The_erratum_stub* stub;
8321       if (erratum_type == ST_E_835769)
8322         stub = new The_erratum_stub(relobj, erratum_type, shndx,
8323                                     erratum_insn_offset);
8324       else if (erratum_type == ST_E_843419)
8325         stub = new E843419_stub<size, big_endian>(
8326             relobj, shndx, erratum_insn_offset, e843419_adrp_offset);
8327       else
8328         gold_unreachable();
8329       stub->set_erratum_insn(erratum_insn);
8330       stub->set_erratum_address(erratum_address);
8331       // For erratum ST_E_843419 and ST_E_835769, the destination address is
8332       // always the next insn after erratum insn.
8333       stub->set_destination_address(erratum_address + BPI);
8334       stub_table->add_erratum_stub(stub);
8335     }
8336 }
8337
8338
8339 // Scan erratum for section SHNDX range [output_address + span_start,
8340 // output_address + span_end). Note here we do not share the code with
8341 // scan_erratum_843419_span function, because for 843419 we optimize by only
8342 // scanning the last few insns of a page, whereas for 835769, we need to scan
8343 // every insn.
8344
8345 template<int size, bool big_endian>
8346 void
8347 Target_aarch64<size, big_endian>::scan_erratum_835769_span(
8348     AArch64_relobj<size, big_endian>*  relobj,
8349     unsigned int shndx,
8350     const section_size_type span_start,
8351     const section_size_type span_end,
8352     unsigned char* input_view,
8353     Address output_address)
8354 {
8355   typedef typename Insn_utilities::Insntype Insntype;
8356
8357   const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
8358
8359   // Adjust output_address and view to the start of span.
8360   output_address += span_start;
8361   input_view += span_start;
8362
8363   section_size_type span_length = span_end - span_start;
8364   section_size_type offset = 0;
8365   for (offset = 0; offset + BPI < span_length; offset += BPI)
8366     {
8367       Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
8368       Insntype insn1 = ip[0];
8369       Insntype insn2 = ip[1];
8370       if (is_erratum_835769_sequence(insn1, insn2))
8371         {
8372           Insntype erratum_insn = insn2;
8373           // "span_start + offset" is the offset for insn1. So for insn2, it is
8374           // "span_start + offset + BPI".
8375           section_size_type erratum_insn_offset = span_start + offset + BPI;
8376           Address erratum_address = output_address + offset + BPI;
8377           gold_info(_("Erratum 835769 found and fixed at \"%s\", "
8378                          "section %d, offset 0x%08x."),
8379                        relobj->name().c_str(), shndx,
8380                        (unsigned int)(span_start + offset));
8381
8382           this->create_erratum_stub(relobj, shndx,
8383                                     erratum_insn_offset, erratum_address,
8384                                     erratum_insn, ST_E_835769);
8385           offset += BPI;  // Skip mac insn.
8386         }
8387     }
8388 }  // End of "Target_aarch64::scan_erratum_835769_span".
8389
8390
8391 // Scan erratum for section SHNDX range
8392 // [output_address + span_start, output_address + span_end).
8393
8394 template<int size, bool big_endian>
8395 void
8396 Target_aarch64<size, big_endian>::scan_erratum_843419_span(
8397     AArch64_relobj<size, big_endian>*  relobj,
8398     unsigned int shndx,
8399     const section_size_type span_start,
8400     const section_size_type span_end,
8401     unsigned char* input_view,
8402     Address output_address)
8403 {
8404   typedef typename Insn_utilities::Insntype Insntype;
8405
8406   // Adjust output_address and view to the start of span.
8407   output_address += span_start;
8408   input_view += span_start;
8409
8410   if ((output_address & 0x03) != 0)
8411     return;
8412
8413   section_size_type offset = 0;
8414   section_size_type span_length = span_end - span_start;
8415   // The first instruction must be ending at 0xFF8 or 0xFFC.
8416   unsigned int page_offset = output_address & 0xFFF;
8417   // Make sure starting position, that is "output_address+offset",
8418   // starts at page position 0xff8 or 0xffc.
8419   if (page_offset < 0xff8)
8420     offset = 0xff8 - page_offset;
8421   while (offset + 3 * Insn_utilities::BYTES_PER_INSN <= span_length)
8422     {
8423       Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
8424       Insntype insn1 = ip[0];
8425       if (Insn_utilities::is_adrp(insn1))
8426         {
8427           Insntype insn2 = ip[1];
8428           Insntype insn3 = ip[2];
8429           Insntype erratum_insn;
8430           unsigned insn_offset;
8431           bool do_report = false;
8432           if (is_erratum_843419_sequence(insn1, insn2, insn3))
8433             {
8434               do_report = true;
8435               erratum_insn = insn3;
8436               insn_offset = 2 * Insn_utilities::BYTES_PER_INSN;
8437             }
8438           else if (offset + 4 * Insn_utilities::BYTES_PER_INSN <= span_length)
8439             {
8440               // Optionally we can have an insn between ins2 and ins3
8441               Insntype insn_opt = ip[2];
8442               // And insn_opt must not be a branch.
8443               if (!Insn_utilities::aarch64_b(insn_opt)
8444                   && !Insn_utilities::aarch64_bl(insn_opt)
8445                   && !Insn_utilities::aarch64_blr(insn_opt)
8446                   && !Insn_utilities::aarch64_br(insn_opt))
8447                 {
8448                   // And insn_opt must not write to dest reg in insn1. However
8449                   // we do a conservative scan, which means we may fix/report
8450                   // more than necessary, but it doesn't hurt.
8451
8452                   Insntype insn4 = ip[3];
8453                   if (is_erratum_843419_sequence(insn1, insn2, insn4))
8454                     {
8455                       do_report = true;
8456                       erratum_insn = insn4;
8457                       insn_offset = 3 * Insn_utilities::BYTES_PER_INSN;
8458                     }
8459                 }
8460             }
8461           if (do_report)
8462             {
8463               unsigned int erratum_insn_offset =
8464                 span_start + offset + insn_offset;
8465               Address erratum_address =
8466                 output_address + offset + insn_offset;
8467               create_erratum_stub(relobj, shndx,
8468                                   erratum_insn_offset, erratum_address,
8469                                   erratum_insn, ST_E_843419,
8470                                   span_start + offset);
8471             }
8472         }
8473
8474       // Advance to next candidate instruction. We only consider instruction
8475       // sequences starting at a page offset of 0xff8 or 0xffc.
8476       page_offset = (output_address + offset) & 0xfff;
8477       if (page_offset == 0xff8)
8478         offset += 4;
8479       else  // (page_offset == 0xffc), we move to next page's 0xff8.
8480         offset += 0xffc;
8481     }
8482 }  // End of "Target_aarch64::scan_erratum_843419_span".
8483
8484
8485 // The selector for aarch64 object files.
8486
8487 template<int size, bool big_endian>
8488 class Target_selector_aarch64 : public Target_selector
8489 {
8490  public:
8491   Target_selector_aarch64();
8492
8493   virtual Target*
8494   do_instantiate_target()
8495   { return new Target_aarch64<size, big_endian>(); }
8496 };
8497
8498 template<>
8499 Target_selector_aarch64<32, true>::Target_selector_aarch64()
8500   : Target_selector(elfcpp::EM_AARCH64, 32, true,
8501                     "elf32-bigaarch64", "aarch64_elf32_be_vec")
8502 { }
8503
8504 template<>
8505 Target_selector_aarch64<32, false>::Target_selector_aarch64()
8506   : Target_selector(elfcpp::EM_AARCH64, 32, false,
8507                     "elf32-littleaarch64", "aarch64_elf32_le_vec")
8508 { }
8509
8510 template<>
8511 Target_selector_aarch64<64, true>::Target_selector_aarch64()
8512   : Target_selector(elfcpp::EM_AARCH64, 64, true,
8513                     "elf64-bigaarch64", "aarch64_elf64_be_vec")
8514 { }
8515
8516 template<>
8517 Target_selector_aarch64<64, false>::Target_selector_aarch64()
8518   : Target_selector(elfcpp::EM_AARCH64, 64, false,
8519                     "elf64-littleaarch64", "aarch64_elf64_le_vec")
8520 { }
8521
8522 Target_selector_aarch64<32, true> target_selector_aarch64elf32b;
8523 Target_selector_aarch64<32, false> target_selector_aarch64elf32;
8524 Target_selector_aarch64<64, true> target_selector_aarch64elfb;
8525 Target_selector_aarch64<64, false> target_selector_aarch64elf;
8526
8527 } // End anonymous namespace.