gold/aarch64.cc

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