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   DwarfDebugInlineSection =
 252     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 253                          MachO::S_ATTR_DEBUG,
 254                          SectionKind::getMetadata());
 255   StackMapSection =
 256     Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 0,
 257                          SectionKind::getMetadata());
 258
 259   TLSExtraDataSection = TLSTLVSection;
 260 }
 261
 262 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 263   switch (T.getArch()) {
 264   case Triple::mips:
 265   case Triple::mipsel:
 266     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
 267     break;
 268   case Triple::mips64:
 269   case Triple::mips64el:
 270     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
 271     break;
 272   case Triple::x86_64:
 273     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
 274                      ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8
 275                                                     : dwarf::DW_EH_PE_sdata4);
 276
 277     break;
 278   default:
 279     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 280     break;
 281   }
 282
 283   switch (T.getArch()) {
 284   case Triple::arm:
 285   case Triple::armeb:
 286   case Triple::thumb:
 287   case Triple::thumbeb:
 288     if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
 289       break;
 290     // Fallthrough if not using EHABI
 291   case Triple::ppc:
 292   case Triple::x86:
 293     PersonalityEncoding = (RelocM == Reloc::PIC_)
 294      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 295      : dwarf::DW_EH_PE_absptr;
 296     LSDAEncoding = (RelocM == Reloc::PIC_)
 297       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 298       : dwarf::DW_EH_PE_absptr;
 299     TTypeEncoding = (RelocM == Reloc::PIC_)
 300      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 301      : dwarf::DW_EH_PE_absptr;
 302     break;
 303   case Triple::x86_64:
 304     if (RelocM == Reloc::PIC_) {
 305       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 306         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 307          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 308       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 309         (CMModel == CodeModel::Small
 310          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 311       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 312         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 313          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 314     } else {
 315       PersonalityEncoding =
 316         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 317         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 318       LSDAEncoding = (CMModel == CodeModel::Small)
 319         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 320       TTypeEncoding = (CMModel == CodeModel::Small)
 321         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 322     }
 323     break;
 324   case Triple::aarch64:
 325   case Triple::aarch64_be:
 326     // The small model guarantees static code/data size < 4GB, but not where it
 327     // will be in memory. Most of these could end up >2GB away so even a signed
 328     // pc-relative 32-bit address is insufficient, theoretically.
 329     if (RelocM == Reloc::PIC_) {
 330       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 331         dwarf::DW_EH_PE_sdata8;
 332       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
 333       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 334         dwarf::DW_EH_PE_sdata8;
 335     } else {
 336       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 337       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 338       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 339     }
 340     break;
 341   case Triple::mips:
 342   case Triple::mipsel:
 343   case Triple::mips64:
 344   case Triple::mips64el:
 345     // MIPS uses indirect pointer to refer personality functions, so that the
 346     // eh_frame section can be read-only.  DW.ref.personality will be generated
 347     // for relocation.
 348     PersonalityEncoding = dwarf::DW_EH_PE_indirect;
 349     break;
 350   case Triple::ppc64:
 351   case Triple::ppc64le:
 352     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 353       dwarf::DW_EH_PE_udata8;
 354     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 355     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 356       dwarf::DW_EH_PE_udata8;
 357     break;
 358   case Triple::sparc:
 359     if (RelocM == Reloc::PIC_) {
 360       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 361       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 362         dwarf::DW_EH_PE_sdata4;
 363       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 364         dwarf::DW_EH_PE_sdata4;
 365     } else {
 366       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 367       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 368       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 369     }
 370     break;
 371   case Triple::sparcv9:
 372     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 373     if (RelocM == Reloc::PIC_) {
 374       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 375         dwarf::DW_EH_PE_sdata4;
 376       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 377         dwarf::DW_EH_PE_sdata4;
 378     } else {
 379       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 380       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 381     }
 382     break;
 383   case Triple::systemz:
 384     // All currently-defined code models guarantee that 4-byte PC-relative
 385     // values will be in range.
 386     if (RelocM == Reloc::PIC_) {
 387       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 388         dwarf::DW_EH_PE_sdata4;
 389       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 390       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 391         dwarf::DW_EH_PE_sdata4;
 392     } else {
 393       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 394       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 395       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 396     }
 397     break;
 398   default:
 399     break;
 400   }
 401
 402   // Solaris requires different flags for .eh_frame to seemingly every other
 403   // platform.
 404   EHSectionType = ELF::SHT_PROGBITS;
 405   EHSectionFlags = ELF::SHF_ALLOC;
 406   if (T.isOSSolaris()) {
 407     if (T.getArch() == Triple::x86_64)
 408       EHSectionType = ELF::SHT_X86_64_UNWIND;
 409     else
 410       EHSectionFlags |= ELF::SHF_WRITE;
 411   }
 412
 413
 414   // ELF
 415   BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 416                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);
 417
 418   TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 419                                    ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);
 420
 421   DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 422                                    ELF::SHF_WRITE | ELF::SHF_ALLOC);
 423
 424   ReadOnlySection =
 425       Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
 426
 427   TLSDataSection =
 428       Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 429                          ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
 430
 431   TLSBSSSection = Ctx->getELFSection(
 432       ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
 433
 434   DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 435                                       ELF::SHF_ALLOC | ELF::SHF_WRITE);
 436
 437   DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 438                                            ELF::SHF_ALLOC | ELF::SHF_WRITE);
 439
 440   DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 441                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);
 442
 443   DataRelROLocalSection = Ctx->getELFSection(
 444       ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE);
 445
 446   MergeableConst4Section =
 447       Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 448                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, "");
 449
 450   MergeableConst8Section =
 451       Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 452                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, "");
 453
 454   MergeableConst16Section =
 455       Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 456                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, "");
 457
 458   StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 459                                          ELF::SHF_ALLOC | ELF::SHF_WRITE);
 460
 461   StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 462                                          ELF::SHF_ALLOC | ELF::SHF_WRITE);
 463
 464   // Exception Handling Sections.
 465
 466   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 467   // it contains relocatable pointers.  In PIC mode, this is probably a big
 468   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 469   // adjusted or this should be a data section.
 470   LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 471                                    ELF::SHF_ALLOC);
 472
 473   COFFDebugSymbolsSection = nullptr;
 474
 475   // Debug Info Sections.
 476   DwarfAbbrevSection =
 477       Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0);
 478   DwarfInfoSection = Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0);
 479   DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0);
 480   DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0);
 481   DwarfPubNamesSection =
 482       Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0);
 483   DwarfPubTypesSection =
 484       Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0);
 485   DwarfGnuPubNamesSection =
 486       Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0);
 487   DwarfGnuPubTypesSection =
 488       Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0);
 489   DwarfStrSection =
 490       Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 491                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
 492   DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0);
 493   DwarfARangesSection =
 494       Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0);
 495   DwarfRangesSection =
 496       Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0);
 497
 498   // DWARF5 Experimental Debug Info
 499
 500   // Accelerator Tables
 501   DwarfAccelNamesSection =
 502       Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0);
 503   DwarfAccelObjCSection =
 504       Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0);
 505   DwarfAccelNamespaceSection =
 506       Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0);
 507   DwarfAccelTypesSection =
 508       Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0);
 509
 510   // Fission Sections
 511   DwarfInfoDWOSection =
 512       Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0);
 513   DwarfTypesDWOSection =
 514       Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0);
 515   DwarfAbbrevDWOSection =
 516       Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0);
 517   DwarfStrDWOSection =
 518       Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 519                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
 520   DwarfLineDWOSection =
 521       Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0);
 522   DwarfLocDWOSection =
 523       Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0);
 524   DwarfStrOffDWOSection =
 525       Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0);
 526   DwarfAddrSection = Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0);
 527
 528   StackMapSection =
 529       Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
 530 }
 531
 532
 533 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 534   bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb;
 535
 536   CommDirectiveSupportsAlignment = true;
 537
 538   // COFF
 539   BSSSection =
 540     Ctx->getCOFFSection(".bss",
 541                         COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
 542                         COFF::IMAGE_SCN_MEM_READ |
 543                         COFF::IMAGE_SCN_MEM_WRITE,
 544                         SectionKind::getBSS());
 545   TextSection =
 546     Ctx->getCOFFSection(".text",
 547                         (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT
 548                                : (COFF::SectionCharacteristics)0) |
 549                         COFF::IMAGE_SCN_CNT_CODE |
 550                         COFF::IMAGE_SCN_MEM_EXECUTE |
 551                         COFF::IMAGE_SCN_MEM_READ,
 552                         SectionKind::getText());
 553   DataSection =
 554     Ctx->getCOFFSection(".data",
 555                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 556                         COFF::IMAGE_SCN_MEM_READ |
 557                         COFF::IMAGE_SCN_MEM_WRITE,
 558                         SectionKind::getDataRel());
 559   ReadOnlySection =
 560     Ctx->getCOFFSection(".rdata",
 561                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 562                         COFF::IMAGE_SCN_MEM_READ,
 563                         SectionKind::getReadOnly());
 564
 565   if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) {
 566     StaticCtorSection =
 567       Ctx->getCOFFSection(".CRT$XCU",
 568                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 569                           COFF::IMAGE_SCN_MEM_READ,
 570                           SectionKind::getReadOnly());
 571     StaticDtorSection =
 572       Ctx->getCOFFSection(".CRT$XTX",
 573                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 574                           COFF::IMAGE_SCN_MEM_READ,
 575                           SectionKind::getReadOnly());
 576   } else {
 577     StaticCtorSection =
 578       Ctx->getCOFFSection(".ctors",
 579                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 580                           COFF::IMAGE_SCN_MEM_READ |
 581                           COFF::IMAGE_SCN_MEM_WRITE,
 582                           SectionKind::getDataRel());
 583     StaticDtorSection =
 584       Ctx->getCOFFSection(".dtors",
 585                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 586                           COFF::IMAGE_SCN_MEM_READ |
 587                           COFF::IMAGE_SCN_MEM_WRITE,
 588                           SectionKind::getDataRel());
 589   }
 590
 591   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 592   // though it contains relocatable pointers.  In PIC mode, this is probably a
 593   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 594   // adjusted or this should be a data section.
 595   assert(T.isOSWindows() && "Windows is the only supported COFF target");
 596   if (T.getArch() == Triple::x86_64) {
 597     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
 598     LSDASection = 0;
 599   } else {
 600     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
 601                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 602                                           COFF::IMAGE_SCN_MEM_READ,
 603                                       SectionKind::getReadOnly());
 604   }
 605
 606   // Debug info.
 607   COFFDebugSymbolsSection =
 608     Ctx->getCOFFSection(".debug$S",
 609                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 610                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 611                         COFF::IMAGE_SCN_MEM_READ,
 612                         SectionKind::getMetadata());
 613
 614   DwarfAbbrevSection =
 615     Ctx->getCOFFSection(".debug_abbrev",
 616                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 617                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 618                         COFF::IMAGE_SCN_MEM_READ,
 619                         SectionKind::getMetadata());
 620   DwarfInfoSection =
 621     Ctx->getCOFFSection(".debug_info",
 622                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 623                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 624                         COFF::IMAGE_SCN_MEM_READ,
 625                         SectionKind::getMetadata());
 626   DwarfLineSection =
 627     Ctx->getCOFFSection(".debug_line",
 628                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 629                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 630                         COFF::IMAGE_SCN_MEM_READ,
 631                         SectionKind::getMetadata());
 632   DwarfFrameSection =
 633     Ctx->getCOFFSection(".debug_frame",
 634                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 635                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 636                         COFF::IMAGE_SCN_MEM_READ,
 637                         SectionKind::getMetadata());
 638   DwarfPubNamesSection =
 639     Ctx->getCOFFSection(".debug_pubnames",
 640                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 641                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 642                         COFF::IMAGE_SCN_MEM_READ,
 643                         SectionKind::getMetadata());
 644   DwarfPubTypesSection =
 645     Ctx->getCOFFSection(".debug_pubtypes",
 646                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 647                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 648                         COFF::IMAGE_SCN_MEM_READ,
 649                         SectionKind::getMetadata());
 650   DwarfGnuPubNamesSection =
 651     Ctx->getCOFFSection(".debug_gnu_pubnames",
 652                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 653                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 654                         COFF::IMAGE_SCN_MEM_READ,
 655                         SectionKind::getMetadata());
 656   DwarfGnuPubTypesSection =
 657     Ctx->getCOFFSection(".debug_gnu_pubtypes",
 658                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 659                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 660                         COFF::IMAGE_SCN_MEM_READ,
 661                         SectionKind::getMetadata());
 662   DwarfStrSection =
 663     Ctx->getCOFFSection(".debug_str",
 664                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 665                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 666                         COFF::IMAGE_SCN_MEM_READ,
 667                         SectionKind::getMetadata());
 668   DwarfLocSection =
 669     Ctx->getCOFFSection(".debug_loc",
 670                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 671                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 672                         COFF::IMAGE_SCN_MEM_READ,
 673                         SectionKind::getMetadata());
 674   DwarfARangesSection =
 675     Ctx->getCOFFSection(".debug_aranges",
 676                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 677                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 678                         COFF::IMAGE_SCN_MEM_READ,
 679                         SectionKind::getMetadata());
 680   DwarfRangesSection =
 681     Ctx->getCOFFSection(".debug_ranges",
 682                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 683                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 684                         COFF::IMAGE_SCN_MEM_READ,
 685                         SectionKind::getMetadata());
 686   DwarfInfoDWOSection =
 687     Ctx->getCOFFSection(".debug_info.dwo",
 688                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 689                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 690                         COFF::IMAGE_SCN_MEM_READ,
 691                         SectionKind::getMetadata());
 692   DwarfTypesDWOSection =
 693     Ctx->getCOFFSection(".debug_types.dwo",
 694                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 695                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 696                         COFF::IMAGE_SCN_MEM_READ,
 697                         SectionKind::getMetadata());
 698   DwarfAbbrevDWOSection =
 699     Ctx->getCOFFSection(".debug_abbrev.dwo",
 700                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 701                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 702                         COFF::IMAGE_SCN_MEM_READ,
 703                         SectionKind::getMetadata());
 704   DwarfStrDWOSection =
 705     Ctx->getCOFFSection(".debug_str.dwo",
 706                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 707                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 708                         COFF::IMAGE_SCN_MEM_READ,
 709                         SectionKind::getMetadata());
 710   DwarfLineDWOSection =
 711     Ctx->getCOFFSection(".debug_line.dwo",
 712                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 713                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 714                         COFF::IMAGE_SCN_MEM_READ,
 715                         SectionKind::getMetadata());
 716   DwarfLocDWOSection =
 717     Ctx->getCOFFSection(".debug_loc.dwo",
 718                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 719                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 720                         COFF::IMAGE_SCN_MEM_READ,
 721                         SectionKind::getMetadata());
 722   DwarfStrOffDWOSection =
 723     Ctx->getCOFFSection(".debug_str_offsets.dwo",
 724                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 725                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 726                         COFF::IMAGE_SCN_MEM_READ,
 727                         SectionKind::getMetadata());
 728   DwarfAddrSection =
 729     Ctx->getCOFFSection(".debug_addr",
 730                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 731                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 732                         COFF::IMAGE_SCN_MEM_READ,
 733                         SectionKind::getMetadata());
 734   DwarfAccelNamesSection =
 735     Ctx->getCOFFSection(".apple_names",
 736                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 737                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 738                         COFF::IMAGE_SCN_MEM_READ,
 739                         SectionKind::getMetadata());
 740   DwarfAccelNamespaceSection =
 741     Ctx->getCOFFSection(".apple_namespaces",
 742                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 743                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 744                         COFF::IMAGE_SCN_MEM_READ,
 745                         SectionKind::getMetadata());
 746   DwarfAccelTypesSection =
 747     Ctx->getCOFFSection(".apple_types",
 748                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 749                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 750                         COFF::IMAGE_SCN_MEM_READ,
 751                         SectionKind::getMetadata());
 752   DwarfAccelObjCSection =
 753     Ctx->getCOFFSection(".apple_objc",
 754                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 755                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 756                         COFF::IMAGE_SCN_MEM_READ,
 757                         SectionKind::getMetadata());
 758
 759   DrectveSection =
 760     Ctx->getCOFFSection(".drectve",
 761                         COFF::IMAGE_SCN_LNK_INFO |
 762                         COFF::IMAGE_SCN_LNK_REMOVE,
 763                         SectionKind::getMetadata());
 764
 765   PDataSection =
 766     Ctx->getCOFFSection(".pdata",
 767                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 768                         COFF::IMAGE_SCN_MEM_READ,
 769                         SectionKind::getDataRel());
 770
 771   XDataSection =
 772     Ctx->getCOFFSection(".xdata",
 773                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 774                         COFF::IMAGE_SCN_MEM_READ,
 775                         SectionKind::getDataRel());
 776
 777   TLSDataSection =
 778     Ctx->getCOFFSection(".tls$",
 779                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 780                         COFF::IMAGE_SCN_MEM_READ |
 781                         COFF::IMAGE_SCN_MEM_WRITE,
 782                         SectionKind::getDataRel());
 783 }
 784
 785 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm,
 786                                             CodeModel::Model cm,
 787                                             MCContext &ctx) {
 788   RelocM = relocm;
 789   CMModel = cm;
 790   Ctx = &ctx;
 791
 792   // Common.
 793   CommDirectiveSupportsAlignment = true;
 794   SupportsWeakOmittedEHFrame = true;
 795   SupportsCompactUnwindWithoutEHFrame = false;
 796
 797   PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
 798       dwarf::DW_EH_PE_absptr;
 799
 800   CompactUnwindDwarfEHFrameOnly = 0;
 801
 802   EHFrameSection = nullptr;             // Created on demand.
 803   CompactUnwindSection = nullptr;       // Used only by selected targets.
 804   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
 805   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
 806   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
 807   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
 808
 809   TT = Triple(T);
 810
 811   Triple::ArchType Arch = TT.getArch();
 812   // FIXME: Checking for Arch here to filter out bogus triples such as
 813   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 814   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 815        Arch == Triple::arm || Arch == Triple::thumb ||
 816        Arch == Triple::aarch64 ||
 817        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 818        Arch == Triple::UnknownArch) &&
 819       (TT.isOSDarwin() || TT.isOSBinFormatMachO())) {
 820     Env = IsMachO;
 821     InitMachOMCObjectFileInfo(TT);
 822   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 823               Arch == Triple::arm || Arch == Triple::thumb) &&
 824              (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) {
 825     Env = IsCOFF;
 826     InitCOFFMCObjectFileInfo(TT);
 827   } else {
 828     Env = IsELF;
 829     InitELFMCObjectFileInfo(TT);
 830   }
 831 }
 832
 833 const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
 834   return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
 835                             0, utostr(Hash));
 836 }
 837
 838 void MCObjectFileInfo::InitEHFrameSection() {
 839   if (Env == IsMachO)
 840     EHFrameSection =
 841       Ctx->getMachOSection("__TEXT", "__eh_frame",
 842                            MachO::S_COALESCED |
 843                            MachO::S_ATTR_NO_TOC |
 844                            MachO::S_ATTR_STRIP_STATIC_SYMS |
 845                            MachO::S_ATTR_LIVE_SUPPORT,
 846                            SectionKind::getReadOnly());
 847   else if (Env == IsELF)
 848     EHFrameSection =
 849         Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
 850   else
 851     EHFrameSection =
 852       Ctx->getCOFFSection(".eh_frame",
 853                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 854                           COFF::IMAGE_SCN_MEM_READ |
 855                           COFF::IMAGE_SCN_MEM_WRITE,
 856                           SectionKind::getDataRel());
 857 }