lib/MC/MCObjectFileInfo.cpp

   1 //===-- MObjectFileInfo.cpp - Object File Information ---------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/MC/MCObjectFileInfo.h"
  11 #include "llvm/ADT/StringExtras.h"
  12 #include "llvm/ADT/Triple.h"
  13 #include "llvm/MC/MCAsmInfo.h"
  14 #include "llvm/MC/MCContext.h"
  15 #include "llvm/MC/MCSection.h"
  16 #include "llvm/MC/MCSectionCOFF.h"
  17 #include "llvm/MC/MCSectionELF.h"
  18 #include "llvm/MC/MCSectionMachO.h"
  19 using namespace llvm;
  20
  21 static bool useCompactUnwind(const Triple &T) {
  22   // Only on darwin.
  23   if (!T.isOSDarwin())
  24     return false;
  25
  26   // aarch64 always has it.
  27   if (T.getArch() == Triple::aarch64)
  28     return true;
  29
  30   // Use it on newer version of OS X.
  31   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
  32     return true;
  33
  34   // And the iOS simulator.
  35   if (T.isiOS() &&
  36       (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86))
  37     return true;
  38
  39   return false;
  40 }
  41
  42 void MCObjectFileInfo::InitMachOMCObjectFileInfo(Triple T) {
  43   // MachO
  44   SupportsWeakOmittedEHFrame = false;
  45
  46   if (T.isOSDarwin() && T.getArch() == Triple::aarch64)
  47     SupportsCompactUnwindWithoutEHFrame = true;
  48
  49   PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel
  50     | dwarf::DW_EH_PE_sdata4;
  51   LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
  52   TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
  53     dwarf::DW_EH_PE_sdata4;
  54
  55   // .comm doesn't support alignment before Leopard.
  56   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
  57     CommDirectiveSupportsAlignment = false;
  58
  59   TextSection // .text
  60     = Ctx->getMachOSection("__TEXT", "__text",
  61                            MachO::S_ATTR_PURE_INSTRUCTIONS,
  62                            SectionKind::getText());
  63   DataSection // .data
  64     = Ctx->getMachOSection("__DATA", "__data", 0,
  65                            SectionKind::getDataRel());
  66
  67   // BSSSection might not be expected initialized on msvc.
  68   BSSSection = nullptr;
  69
  70   TLSDataSection // .tdata
  71     = Ctx->getMachOSection("__DATA", "__thread_data",
  72                            MachO::S_THREAD_LOCAL_REGULAR,
  73                            SectionKind::getDataRel());
  74   TLSBSSSection // .tbss
  75     = Ctx->getMachOSection("__DATA", "__thread_bss",
  76                            MachO::S_THREAD_LOCAL_ZEROFILL,
  77                            SectionKind::getThreadBSS());
  78
  79   // TODO: Verify datarel below.
  80   TLSTLVSection // .tlv
  81     = Ctx->getMachOSection("__DATA", "__thread_vars",
  82                            MachO::S_THREAD_LOCAL_VARIABLES,
  83                            SectionKind::getDataRel());
  84
  85   TLSThreadInitSection
  86     = Ctx->getMachOSection("__DATA", "__thread_init",
  87                           MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
  88                           SectionKind::getDataRel());
  89
  90   CStringSection // .cstring
  91     = Ctx->getMachOSection("__TEXT", "__cstring",
  92                            MachO::S_CSTRING_LITERALS,
  93                            SectionKind::getMergeable1ByteCString());
  94   UStringSection
  95     = Ctx->getMachOSection("__TEXT","__ustring", 0,
  96                            SectionKind::getMergeable2ByteCString());
  97   FourByteConstantSection // .literal4
  98     = Ctx->getMachOSection("__TEXT", "__literal4",
  99                            MachO::S_4BYTE_LITERALS,
 100                            SectionKind::getMergeableConst4());
 101   EightByteConstantSection // .literal8
 102     = Ctx->getMachOSection("__TEXT", "__literal8",
 103                            MachO::S_8BYTE_LITERALS,
 104                            SectionKind::getMergeableConst8());
 105
 106   SixteenByteConstantSection // .literal16
 107       = Ctx->getMachOSection("__TEXT", "__literal16",
 108                              MachO::S_16BYTE_LITERALS,
 109                              SectionKind::getMergeableConst16());
 110
 111   ReadOnlySection  // .const
 112     = Ctx->getMachOSection("__TEXT", "__const", 0,
 113                            SectionKind::getReadOnly());
 114
 115   TextCoalSection
 116     = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
 117                            MachO::S_COALESCED |
 118                            MachO::S_ATTR_PURE_INSTRUCTIONS,
 119                            SectionKind::getText());
 120   ConstTextCoalSection
 121     = Ctx->getMachOSection("__TEXT", "__const_coal",
 122                            MachO::S_COALESCED,
 123                            SectionKind::getReadOnly());
 124   ConstDataSection  // .const_data
 125     = Ctx->getMachOSection("__DATA", "__const", 0,
 126                            SectionKind::getReadOnlyWithRel());
 127   DataCoalSection
 128     = Ctx->getMachOSection("__DATA","__datacoal_nt",
 129                            MachO::S_COALESCED,
 130                            SectionKind::getDataRel());
 131   DataCommonSection
 132     = Ctx->getMachOSection("__DATA","__common",
 133                            MachO::S_ZEROFILL,
 134                            SectionKind::getBSS());
 135   DataBSSSection
 136     = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
 137                            SectionKind::getBSS());
 138
 139
 140   LazySymbolPointerSection
 141     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
 142                            MachO::S_LAZY_SYMBOL_POINTERS,
 143                            SectionKind::getMetadata());
 144   NonLazySymbolPointerSection
 145     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
 146                            MachO::S_NON_LAZY_SYMBOL_POINTERS,
 147                            SectionKind::getMetadata());
 148
 149   if (RelocM == Reloc::Static) {
 150     StaticCtorSection
 151       = Ctx->getMachOSection("__TEXT", "__constructor", 0,
 152                              SectionKind::getDataRel());
 153     StaticDtorSection
 154       = Ctx->getMachOSection("__TEXT", "__destructor", 0,
 155                              SectionKind::getDataRel());
 156   } else {
 157     StaticCtorSection
 158       = Ctx->getMachOSection("__DATA", "__mod_init_func",
 159                              MachO::S_MOD_INIT_FUNC_POINTERS,
 160                              SectionKind::getDataRel());
 161     StaticDtorSection
 162       = Ctx->getMachOSection("__DATA", "__mod_term_func",
 163                              MachO::S_MOD_TERM_FUNC_POINTERS,
 164                              SectionKind::getDataRel());
 165   }
 166
 167   // Exception Handling.
 168   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
 169                                      SectionKind::getReadOnlyWithRel());
 170
 171   COFFDebugSymbolsSection = nullptr;
 172
 173   if (useCompactUnwind(T)) {
 174     CompactUnwindSection =
 175         Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
 176                              SectionKind::getReadOnly());
 177
 178     if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)
 179       CompactUnwindDwarfEHFrameOnly = 0x04000000;
 180     else if (T.getArch() == Triple::aarch64)
 181       CompactUnwindDwarfEHFrameOnly = 0x03000000;
 182   }
 183
 184   // Debug Information.
 185   DwarfAccelNamesSection =
 186     Ctx->getMachOSection("__DWARF", "__apple_names",
 187                          MachO::S_ATTR_DEBUG,
 188                          SectionKind::getMetadata());
 189   DwarfAccelObjCSection =
 190     Ctx->getMachOSection("__DWARF", "__apple_objc",
 191                          MachO::S_ATTR_DEBUG,
 192                          SectionKind::getMetadata());
 193   // 16 character section limit...
 194   DwarfAccelNamespaceSection =
 195     Ctx->getMachOSection("__DWARF", "__apple_namespac",
 196                          MachO::S_ATTR_DEBUG,
 197                          SectionKind::getMetadata());
 198   DwarfAccelTypesSection =
 199     Ctx->getMachOSection("__DWARF", "__apple_types",
 200                          MachO::S_ATTR_DEBUG,
 201                          SectionKind::getMetadata());
 202
 203   DwarfAbbrevSection =
 204     Ctx->getMachOSection("__DWARF", "__debug_abbrev",
 205                          MachO::S_ATTR_DEBUG,
 206                          SectionKind::getMetadata());
 207   DwarfInfoSection =
 208     Ctx->getMachOSection("__DWARF", "__debug_info",
 209                          MachO::S_ATTR_DEBUG,
 210                          SectionKind::getMetadata());
 211   DwarfLineSection =
 212     Ctx->getMachOSection("__DWARF", "__debug_line",
 213                          MachO::S_ATTR_DEBUG,
 214                          SectionKind::getMetadata());
 215   DwarfFrameSection =
 216     Ctx->getMachOSection("__DWARF", "__debug_frame",
 217                          MachO::S_ATTR_DEBUG,
 218                          SectionKind::getMetadata());
 219   DwarfPubNamesSection =
 220     Ctx->getMachOSection("__DWARF", "__debug_pubnames",
 221                          MachO::S_ATTR_DEBUG,
 222                          SectionKind::getMetadata());
 223   DwarfPubTypesSection =
 224     Ctx->getMachOSection("__DWARF", "__debug_pubtypes",
 225                          MachO::S_ATTR_DEBUG,
 226                          SectionKind::getMetadata());
 227   DwarfGnuPubNamesSection =
 228     Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn",
 229                          MachO::S_ATTR_DEBUG,
 230                          SectionKind::getMetadata());
 231   DwarfGnuPubTypesSection =
 232     Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt",
 233                          MachO::S_ATTR_DEBUG,
 234                          SectionKind::getMetadata());
 235   DwarfStrSection =
 236     Ctx->getMachOSection("__DWARF", "__debug_str",
 237                          MachO::S_ATTR_DEBUG,
 238                          SectionKind::getMetadata());
 239   DwarfLocSection =
 240     Ctx->getMachOSection("__DWARF", "__debug_loc",
 241                          MachO::S_ATTR_DEBUG,
 242                          SectionKind::getMetadata());
 243   DwarfARangesSection =
 244     Ctx->getMachOSection("__DWARF", "__debug_aranges",
 245                          MachO::S_ATTR_DEBUG,
 246                          SectionKind::getMetadata());
 247   DwarfRangesSection =
 248     Ctx->getMachOSection("__DWARF", "__debug_ranges",
 249                          MachO::S_ATTR_DEBUG,
 250                          SectionKind::getMetadata());
 251   DwarfMacroInfoSection =
 252     Ctx->getMachOSection("__DWARF", "__debug_macinfo",
 253                          MachO::S_ATTR_DEBUG,
 254                          SectionKind::getMetadata());
 255   DwarfDebugInlineSection =
 256     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 257                          MachO::S_ATTR_DEBUG,
 258                          SectionKind::getMetadata());
 259   StackMapSection =
 260     Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 0,
 261                          SectionKind::getMetadata());
 262
 263   TLSExtraDataSection = TLSTLVSection;
 264 }
 265
 266 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 267   switch (T.getArch()) {
 268   case Triple::mips:
 269   case Triple::mipsel:
 270     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
 271     break;
 272   case Triple::mips64:
 273   case Triple::mips64el:
 274     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
 275     break;
 276   case Triple::x86_64:
 277     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
 278                      ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8
 279                                                     : dwarf::DW_EH_PE_sdata4);
 280
 281     break;
 282   default:
 283     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 284     break;
 285   }
 286
 287   switch (T.getArch()) {
 288   case Triple::arm:
 289   case Triple::armeb:
 290   case Triple::thumb:
 291   case Triple::thumbeb:
 292     if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
 293       break;
 294     // Fallthrough if not using EHABI
 295   case Triple::ppc:
 296   case Triple::x86:
 297     PersonalityEncoding = (RelocM == Reloc::PIC_)
 298      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 299      : dwarf::DW_EH_PE_absptr;
 300     LSDAEncoding = (RelocM == Reloc::PIC_)
 301       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 302       : dwarf::DW_EH_PE_absptr;
 303     TTypeEncoding = (RelocM == Reloc::PIC_)
 304      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 305      : dwarf::DW_EH_PE_absptr;
 306     break;
 307   case Triple::x86_64:
 308     if (RelocM == Reloc::PIC_) {
 309       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 310         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 311          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 312       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 313         (CMModel == CodeModel::Small
 314          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 315       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 316         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 317          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 318     } else {
 319       PersonalityEncoding =
 320         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 321         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 322       LSDAEncoding = (CMModel == CodeModel::Small)
 323         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 324       TTypeEncoding = (CMModel == CodeModel::Small)
 325         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 326     }
 327     break;
 328   case Triple::aarch64:
 329   case Triple::aarch64_be:
 330     // The small model guarantees static code/data size < 4GB, but not where it
 331     // will be in memory. Most of these could end up >2GB away so even a signed
 332     // pc-relative 32-bit address is insufficient, theoretically.
 333     if (RelocM == Reloc::PIC_) {
 334       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 335         dwarf::DW_EH_PE_sdata8;
 336       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
 337       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 338         dwarf::DW_EH_PE_sdata8;
 339     } else {
 340       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 341       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 342       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 343     }
 344     break;
 345   case Triple::mips:
 346   case Triple::mipsel:
 347   case Triple::mips64:
 348   case Triple::mips64el:
 349     // MIPS uses indirect pointer to refer personality functions, so that the
 350     // eh_frame section can be read-only.  DW.ref.personality will be generated
 351     // for relocation.
 352     PersonalityEncoding = dwarf::DW_EH_PE_indirect;
 353     break;
 354   case Triple::ppc64:
 355   case Triple::ppc64le:
 356     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 357       dwarf::DW_EH_PE_udata8;
 358     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 359     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 360       dwarf::DW_EH_PE_udata8;
 361     break;
 362   case Triple::sparc:
 363     if (RelocM == Reloc::PIC_) {
 364       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 365       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 366         dwarf::DW_EH_PE_sdata4;
 367       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 368         dwarf::DW_EH_PE_sdata4;
 369     } else {
 370       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 371       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 372       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 373     }
 374     break;
 375   case Triple::sparcv9:
 376     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 377     if (RelocM == Reloc::PIC_) {
 378       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 379         dwarf::DW_EH_PE_sdata4;
 380       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 381         dwarf::DW_EH_PE_sdata4;
 382     } else {
 383       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 384       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 385     }
 386     break;
 387   case Triple::systemz:
 388     // All currently-defined code models guarantee that 4-byte PC-relative
 389     // values will be in range.
 390     if (RelocM == Reloc::PIC_) {
 391       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 392         dwarf::DW_EH_PE_sdata4;
 393       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 394       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 395         dwarf::DW_EH_PE_sdata4;
 396     } else {
 397       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 398       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 399       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 400     }
 401     break;
 402   default:
 403     break;
 404   }
 405
 406   // Solaris requires different flags for .eh_frame to seemingly every other
 407   // platform.
 408   EHSectionType = ELF::SHT_PROGBITS;
 409   EHSectionFlags = ELF::SHF_ALLOC;
 410   if (T.isOSSolaris()) {
 411     if (T.getArch() == Triple::x86_64)
 412       EHSectionType = ELF::SHT_X86_64_UNWIND;
 413     else
 414       EHSectionFlags |= ELF::SHF_WRITE;
 415   }
 416
 417
 418   // ELF
 419   BSSSection =
 420     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 421                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 422                        SectionKind::getBSS());
 423
 424   TextSection =
 425     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 426                        ELF::SHF_EXECINSTR |
 427                        ELF::SHF_ALLOC,
 428                        SectionKind::getText());
 429
 430   DataSection =
 431     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 432                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 433                        SectionKind::getDataRel());
 434
 435   ReadOnlySection =
 436     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 437                        ELF::SHF_ALLOC,
 438                        SectionKind::getReadOnly());
 439
 440   TLSDataSection =
 441     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 442                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 443                        ELF::SHF_WRITE,
 444                        SectionKind::getThreadData());
 445
 446   TLSBSSSection =
 447     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 448                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 449                        ELF::SHF_WRITE,
 450                        SectionKind::getThreadBSS());
 451
 452   DataRelSection =
 453     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 454                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 455                        SectionKind::getDataRel());
 456
 457   DataRelLocalSection =
 458     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 459                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 460                        SectionKind::getDataRelLocal());
 461
 462   DataRelROSection =
 463     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 464                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 465                        SectionKind::getReadOnlyWithRel());
 466
 467   DataRelROLocalSection =
 468     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 469                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 470                        SectionKind::getReadOnlyWithRelLocal());
 471
 472   MergeableConst4Section =
 473     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 474                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 475                        SectionKind::getMergeableConst4());
 476
 477   MergeableConst8Section =
 478     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 479                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 480                        SectionKind::getMergeableConst8());
 481
 482   MergeableConst16Section =
 483     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 484                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 485                        SectionKind::getMergeableConst16());
 486
 487   StaticCtorSection =
 488     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 489                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 490                        SectionKind::getDataRel());
 491
 492   StaticDtorSection =
 493     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 494                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 495                        SectionKind::getDataRel());
 496
 497   // Exception Handling Sections.
 498
 499   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 500   // it contains relocatable pointers.  In PIC mode, this is probably a big
 501   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 502   // adjusted or this should be a data section.
 503   LSDASection =
 504     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 505                        ELF::SHF_ALLOC,
 506                        SectionKind::getReadOnly());
 507
 508   COFFDebugSymbolsSection = nullptr;
 509
 510   // Debug Info Sections.
 511   DwarfAbbrevSection =
 512     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 513                        SectionKind::getMetadata());
 514   DwarfInfoSection =
 515     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 516                        SectionKind::getMetadata());
 517   DwarfLineSection =
 518     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 519                        SectionKind::getMetadata());
 520   DwarfFrameSection =
 521     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 522                        SectionKind::getMetadata());
 523   DwarfPubNamesSection =
 524     Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0,
 525                        SectionKind::getMetadata());
 526   DwarfPubTypesSection =
 527     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 528                        SectionKind::getMetadata());
 529   DwarfGnuPubNamesSection =
 530     Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0,
 531                        SectionKind::getMetadata());
 532   DwarfGnuPubTypesSection =
 533     Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0,
 534                        SectionKind::getMetadata());
 535   DwarfStrSection =
 536     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 537                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 538                        SectionKind::getMergeable1ByteCString());
 539   DwarfLocSection =
 540     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 541                        SectionKind::getMetadata());
 542   DwarfARangesSection =
 543     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 544                        SectionKind::getMetadata());
 545   DwarfRangesSection =
 546     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 547                        SectionKind::getMetadata());
 548   DwarfMacroInfoSection =
 549     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 550                        SectionKind::getMetadata());
 551
 552   // DWARF5 Experimental Debug Info
 553
 554   // Accelerator Tables
 555   DwarfAccelNamesSection =
 556     Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0,
 557                        SectionKind::getMetadata());
 558   DwarfAccelObjCSection =
 559     Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0,
 560                        SectionKind::getMetadata());
 561   DwarfAccelNamespaceSection =
 562     Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0,
 563                        SectionKind::getMetadata());
 564   DwarfAccelTypesSection =
 565     Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0,
 566                        SectionKind::getMetadata());
 567
 568   // Fission Sections
 569   DwarfInfoDWOSection =
 570     Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0,
 571                        SectionKind::getMetadata());
 572   DwarfTypesDWOSection =
 573     Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0,
 574                        SectionKind::getMetadata());
 575   DwarfAbbrevDWOSection =
 576     Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0,
 577                        SectionKind::getMetadata());
 578   DwarfStrDWOSection =
 579     Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 580                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 581                        SectionKind::getMergeable1ByteCString());
 582   DwarfLineDWOSection =
 583     Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0,
 584                        SectionKind::getMetadata());
 585   DwarfLocDWOSection =
 586     Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0,
 587                        SectionKind::getMetadata());
 588   DwarfStrOffDWOSection =
 589     Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0,
 590                        SectionKind::getMetadata());
 591   DwarfAddrSection =
 592     Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0,
 593                        SectionKind::getMetadata());
 594
 595   StackMapSection =
 596     Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS,
 597                        ELF::SHF_ALLOC,
 598                        SectionKind::getMetadata());
 599
 600 }
 601
 602
 603 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 604   bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb;
 605
 606   CommDirectiveSupportsAlignment = true;
 607
 608   // COFF
 609   BSSSection =
 610     Ctx->getCOFFSection(".bss",
 611                         COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
 612                         COFF::IMAGE_SCN_MEM_READ |
 613                         COFF::IMAGE_SCN_MEM_WRITE,
 614                         SectionKind::getBSS());
 615   TextSection =
 616     Ctx->getCOFFSection(".text",
 617                         (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT
 618                                : (COFF::SectionCharacteristics)0) |
 619                         COFF::IMAGE_SCN_CNT_CODE |
 620                         COFF::IMAGE_SCN_MEM_EXECUTE |
 621                         COFF::IMAGE_SCN_MEM_READ,
 622                         SectionKind::getText());
 623   DataSection =
 624     Ctx->getCOFFSection(".data",
 625                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 626                         COFF::IMAGE_SCN_MEM_READ |
 627                         COFF::IMAGE_SCN_MEM_WRITE,
 628                         SectionKind::getDataRel());
 629   ReadOnlySection =
 630     Ctx->getCOFFSection(".rdata",
 631                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 632                         COFF::IMAGE_SCN_MEM_READ,
 633                         SectionKind::getReadOnly());
 634
 635   if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) {
 636     StaticCtorSection =
 637       Ctx->getCOFFSection(".CRT$XCU",
 638                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 639                           COFF::IMAGE_SCN_MEM_READ,
 640                           SectionKind::getReadOnly());
 641     StaticDtorSection =
 642       Ctx->getCOFFSection(".CRT$XTX",
 643                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 644                           COFF::IMAGE_SCN_MEM_READ,
 645                           SectionKind::getReadOnly());
 646   } else {
 647     StaticCtorSection =
 648       Ctx->getCOFFSection(".ctors",
 649                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 650                           COFF::IMAGE_SCN_MEM_READ |
 651                           COFF::IMAGE_SCN_MEM_WRITE,
 652                           SectionKind::getDataRel());
 653     StaticDtorSection =
 654       Ctx->getCOFFSection(".dtors",
 655                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 656                           COFF::IMAGE_SCN_MEM_READ |
 657                           COFF::IMAGE_SCN_MEM_WRITE,
 658                           SectionKind::getDataRel());
 659   }
 660
 661   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 662   // though it contains relocatable pointers.  In PIC mode, this is probably a
 663   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 664   // adjusted or this should be a data section.
 665   assert(T.isOSWindows() && "Windows is the only supported COFF target");
 666   if (T.getArch() == Triple::x86_64) {
 667     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
 668     LSDASection = 0;
 669   } else {
 670     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
 671                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 672                                           COFF::IMAGE_SCN_MEM_READ,
 673                                       SectionKind::getReadOnly());
 674   }
 675
 676   // Debug info.
 677   COFFDebugSymbolsSection =
 678     Ctx->getCOFFSection(".debug$S",
 679                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 680                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 681                         COFF::IMAGE_SCN_MEM_READ,
 682                         SectionKind::getMetadata());
 683
 684   DwarfAbbrevSection =
 685     Ctx->getCOFFSection(".debug_abbrev",
 686                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 687                         COFF::IMAGE_SCN_MEM_READ,
 688                         SectionKind::getMetadata());
 689   DwarfInfoSection =
 690     Ctx->getCOFFSection(".debug_info",
 691                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 692                         COFF::IMAGE_SCN_MEM_READ,
 693                         SectionKind::getMetadata());
 694   DwarfLineSection =
 695     Ctx->getCOFFSection(".debug_line",
 696                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 697                         COFF::IMAGE_SCN_MEM_READ,
 698                         SectionKind::getMetadata());
 699   DwarfFrameSection =
 700     Ctx->getCOFFSection(".debug_frame",
 701                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 702                         COFF::IMAGE_SCN_MEM_READ,
 703                         SectionKind::getMetadata());
 704   DwarfPubNamesSection =
 705     Ctx->getCOFFSection(".debug_pubnames",
 706                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 707                         COFF::IMAGE_SCN_MEM_READ,
 708                         SectionKind::getMetadata());
 709   DwarfPubTypesSection =
 710     Ctx->getCOFFSection(".debug_pubtypes",
 711                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 712                         COFF::IMAGE_SCN_MEM_READ,
 713                         SectionKind::getMetadata());
 714   DwarfGnuPubNamesSection =
 715     Ctx->getCOFFSection(".debug_gnu_pubnames",
 716                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 717                         COFF::IMAGE_SCN_MEM_READ,
 718                         SectionKind::getMetadata());
 719   DwarfGnuPubTypesSection =
 720     Ctx->getCOFFSection(".debug_gnu_pubtypes",
 721                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 722                         COFF::IMAGE_SCN_MEM_READ,
 723                         SectionKind::getMetadata());
 724   DwarfStrSection =
 725     Ctx->getCOFFSection(".debug_str",
 726                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 727                         COFF::IMAGE_SCN_MEM_READ,
 728                         SectionKind::getMetadata());
 729   DwarfLocSection =
 730     Ctx->getCOFFSection(".debug_loc",
 731                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 732                         COFF::IMAGE_SCN_MEM_READ,
 733                         SectionKind::getMetadata());
 734   DwarfARangesSection =
 735     Ctx->getCOFFSection(".debug_aranges",
 736                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 737                         COFF::IMAGE_SCN_MEM_READ,
 738                         SectionKind::getMetadata());
 739   DwarfRangesSection =
 740     Ctx->getCOFFSection(".debug_ranges",
 741                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 742                         COFF::IMAGE_SCN_MEM_READ,
 743                         SectionKind::getMetadata());
 744   DwarfMacroInfoSection =
 745     Ctx->getCOFFSection(".debug_macinfo",
 746                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 747                         COFF::IMAGE_SCN_MEM_READ,
 748                         SectionKind::getMetadata());
 749   DwarfInfoDWOSection =
 750       Ctx->getCOFFSection(".debug_info.dwo",
 751                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 752                           COFF::IMAGE_SCN_MEM_READ,
 753                           SectionKind::getMetadata());
 754   DwarfTypesDWOSection =
 755       Ctx->getCOFFSection(".debug_types.dwo", COFF::IMAGE_SCN_MEM_DISCARDABLE |
 756                                                   COFF::IMAGE_SCN_MEM_READ,
 757                           SectionKind::getMetadata());
 758   DwarfAbbrevDWOSection =
 759       Ctx->getCOFFSection(".debug_abbrev.dwo",
 760                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 761                           COFF::IMAGE_SCN_MEM_READ,
 762                           SectionKind::getMetadata());
 763   DwarfStrDWOSection =
 764       Ctx->getCOFFSection(".debug_str.dwo",
 765                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 766                           COFF::IMAGE_SCN_MEM_READ,
 767                           SectionKind::getMetadata());
 768   DwarfLineDWOSection =
 769       Ctx->getCOFFSection(".debug_line.dwo",
 770                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 771                           COFF::IMAGE_SCN_MEM_READ,
 772                           SectionKind::getMetadata());
 773   DwarfLocDWOSection =
 774       Ctx->getCOFFSection(".debug_loc.dwo",
 775                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 776                           COFF::IMAGE_SCN_MEM_READ,
 777                           SectionKind::getMetadata());
 778   DwarfStrOffDWOSection =
 779       Ctx->getCOFFSection(".debug_str_offsets.dwo",
 780                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 781                           COFF::IMAGE_SCN_MEM_READ,
 782                           SectionKind::getMetadata());
 783
 784   DwarfAddrSection =
 785     Ctx->getCOFFSection(".debug_addr",
 786                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 787                         COFF::IMAGE_SCN_MEM_READ,
 788                         SectionKind::getMetadata());
 789
 790   DwarfAccelNamesSection =
 791       Ctx->getCOFFSection(".apple_names",
 792                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 793                           COFF::IMAGE_SCN_MEM_READ,
 794                           SectionKind::getMetadata());
 795   DwarfAccelNamespaceSection =
 796       Ctx->getCOFFSection(".apple_namespaces",
 797                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 798                           COFF::IMAGE_SCN_MEM_READ,
 799                           SectionKind::getMetadata());
 800   DwarfAccelTypesSection =
 801       Ctx->getCOFFSection(".apple_types",
 802                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 803                           COFF::IMAGE_SCN_MEM_READ,
 804                           SectionKind::getMetadata());
 805   DwarfAccelObjCSection =
 806       Ctx->getCOFFSection(".apple_objc",
 807                           COFF::IMAGE_SCN_MEM_DISCARDABLE |
 808                           COFF::IMAGE_SCN_MEM_READ,
 809                           SectionKind::getMetadata());
 810
 811   DrectveSection =
 812     Ctx->getCOFFSection(".drectve",
 813                         COFF::IMAGE_SCN_LNK_INFO |
 814                         COFF::IMAGE_SCN_LNK_REMOVE,
 815                         SectionKind::getMetadata());
 816
 817   PDataSection =
 818     Ctx->getCOFFSection(".pdata",
 819                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 820                         COFF::IMAGE_SCN_MEM_READ,
 821                         SectionKind::getDataRel());
 822
 823   XDataSection =
 824     Ctx->getCOFFSection(".xdata",
 825                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 826                         COFF::IMAGE_SCN_MEM_READ,
 827                         SectionKind::getDataRel());
 828
 829   TLSDataSection =
 830     Ctx->getCOFFSection(".tls$",
 831                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 832                         COFF::IMAGE_SCN_MEM_READ |
 833                         COFF::IMAGE_SCN_MEM_WRITE,
 834                         SectionKind::getDataRel());
 835 }
 836
 837 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm,
 838                                             CodeModel::Model cm,
 839                                             MCContext &ctx) {
 840   RelocM = relocm;
 841   CMModel = cm;
 842   Ctx = &ctx;
 843
 844   // Common.
 845   CommDirectiveSupportsAlignment = true;
 846   SupportsWeakOmittedEHFrame = true;
 847   SupportsCompactUnwindWithoutEHFrame = false;
 848
 849   PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
 850       dwarf::DW_EH_PE_absptr;
 851
 852   CompactUnwindDwarfEHFrameOnly = 0;
 853
 854   EHFrameSection = nullptr;             // Created on demand.
 855   CompactUnwindSection = nullptr;       // Used only by selected targets.
 856   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
 857   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
 858   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
 859   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
 860
 861   TT = Triple(T);
 862
 863   Triple::ArchType Arch = TT.getArch();
 864   // FIXME: Checking for Arch here to filter out bogus triples such as
 865   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 866   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 867        Arch == Triple::arm || Arch == Triple::thumb ||
 868        Arch == Triple::aarch64 ||
 869        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 870        Arch == Triple::UnknownArch) &&
 871       (TT.isOSDarwin() || TT.isOSBinFormatMachO())) {
 872     Env = IsMachO;
 873     InitMachOMCObjectFileInfo(TT);
 874   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 875               Arch == Triple::arm || Arch == Triple::thumb) &&
 876              (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) {
 877     Env = IsCOFF;
 878     InitCOFFMCObjectFileInfo(TT);
 879   } else {
 880     Env = IsELF;
 881     InitELFMCObjectFileInfo(TT);
 882   }
 883 }
 884
 885 const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
 886   return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
 887                             SectionKind::getMetadata(), 0, utostr(Hash));
 888 }
 889
 890 void MCObjectFileInfo::InitEHFrameSection() {
 891   if (Env == IsMachO)
 892     EHFrameSection =
 893       Ctx->getMachOSection("__TEXT", "__eh_frame",
 894                            MachO::S_COALESCED |
 895                            MachO::S_ATTR_NO_TOC |
 896                            MachO::S_ATTR_STRIP_STATIC_SYMS |
 897                            MachO::S_ATTR_LIVE_SUPPORT,
 898                            SectionKind::getReadOnly());
 899   else if (Env == IsELF)
 900     EHFrameSection =
 901       Ctx->getELFSection(".eh_frame", EHSectionType,
 902                          EHSectionFlags,
 903                          SectionKind::getDataRel());
 904   else
 905     EHFrameSection =
 906       Ctx->getCOFFSection(".eh_frame",
 907                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 908                           COFF::IMAGE_SCN_MEM_READ |
 909                           COFF::IMAGE_SCN_MEM_WRITE,
 910                           SectionKind::getDataRel());
 911 }