gold/aarch64.cc

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