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/Triple.h"
  12 #include "llvm/MC/MCContext.h"
  13 #include "llvm/MC/MCSection.h"
  14 #include "llvm/MC/MCSectionCOFF.h"
  15 #include "llvm/MC/MCSectionELF.h"
  16 #include "llvm/MC/MCSectionMachO.h"
  17 using namespace llvm;
  18
  19 void MCObjectFileInfo::InitMachOMCObjectFileInfo(Triple T) {
  20   // MachO
  21   IsFunctionEHFrameSymbolPrivate = false;
  22   SupportsWeakOmittedEHFrame = false;
  23
  24   PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel
  25     | dwarf::DW_EH_PE_sdata4;
  26   LSDAEncoding = FDEEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
  27   TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
  28     dwarf::DW_EH_PE_sdata4;
  29
  30   // .comm doesn't support alignment before Leopard.
  31   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
  32     CommDirectiveSupportsAlignment = false;
  33
  34   TextSection // .text
  35     = Ctx->getMachOSection("__TEXT", "__text",
  36                            MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
  37                            SectionKind::getText());
  38   DataSection // .data
  39     = Ctx->getMachOSection("__DATA", "__data", 0,
  40                            SectionKind::getDataRel());
  41
  42   TLSDataSection // .tdata
  43     = Ctx->getMachOSection("__DATA", "__thread_data",
  44                            MCSectionMachO::S_THREAD_LOCAL_REGULAR,
  45                            SectionKind::getDataRel());
  46   TLSBSSSection // .tbss
  47     = Ctx->getMachOSection("__DATA", "__thread_bss",
  48                            MCSectionMachO::S_THREAD_LOCAL_ZEROFILL,
  49                            SectionKind::getThreadBSS());
  50
  51   // TODO: Verify datarel below.
  52   TLSTLVSection // .tlv
  53     = Ctx->getMachOSection("__DATA", "__thread_vars",
  54                            MCSectionMachO::S_THREAD_LOCAL_VARIABLES,
  55                            SectionKind::getDataRel());
  56
  57   TLSThreadInitSection
  58     = Ctx->getMachOSection("__DATA", "__thread_init",
  59                           MCSectionMachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
  60                           SectionKind::getDataRel());
  61
  62   CStringSection // .cstring
  63     = Ctx->getMachOSection("__TEXT", "__cstring",
  64                            MCSectionMachO::S_CSTRING_LITERALS,
  65                            SectionKind::getMergeable1ByteCString());
  66   UStringSection
  67     = Ctx->getMachOSection("__TEXT","__ustring", 0,
  68                            SectionKind::getMergeable2ByteCString());
  69   FourByteConstantSection // .literal4
  70     = Ctx->getMachOSection("__TEXT", "__literal4",
  71                            MCSectionMachO::S_4BYTE_LITERALS,
  72                            SectionKind::getMergeableConst4());
  73   EightByteConstantSection // .literal8
  74     = Ctx->getMachOSection("__TEXT", "__literal8",
  75                            MCSectionMachO::S_8BYTE_LITERALS,
  76                            SectionKind::getMergeableConst8());
  77
  78   // ld_classic doesn't support .literal16 in 32-bit mode, and ld64 falls back
  79   // to using it in -static mode.
  80   SixteenByteConstantSection = 0;
  81   if (RelocM != Reloc::Static &&
  82       T.getArch() != Triple::x86_64 && T.getArch() != Triple::ppc64)
  83     SixteenByteConstantSection =   // .literal16
  84       Ctx->getMachOSection("__TEXT", "__literal16",
  85                            MCSectionMachO::S_16BYTE_LITERALS,
  86                            SectionKind::getMergeableConst16());
  87
  88   ReadOnlySection  // .const
  89     = Ctx->getMachOSection("__TEXT", "__const", 0,
  90                            SectionKind::getReadOnly());
  91
  92   TextCoalSection
  93     = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
  94                            MCSectionMachO::S_COALESCED |
  95                            MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
  96                            SectionKind::getText());
  97   ConstTextCoalSection
  98     = Ctx->getMachOSection("__TEXT", "__const_coal",
  99                            MCSectionMachO::S_COALESCED,
 100                            SectionKind::getReadOnly());
 101   ConstDataSection  // .const_data
 102     = Ctx->getMachOSection("__DATA", "__const", 0,
 103                            SectionKind::getReadOnlyWithRel());
 104   DataCoalSection
 105     = Ctx->getMachOSection("__DATA","__datacoal_nt",
 106                            MCSectionMachO::S_COALESCED,
 107                            SectionKind::getDataRel());
 108   DataCommonSection
 109     = Ctx->getMachOSection("__DATA","__common",
 110                            MCSectionMachO::S_ZEROFILL,
 111                            SectionKind::getBSS());
 112   DataBSSSection
 113     = Ctx->getMachOSection("__DATA","__bss", MCSectionMachO::S_ZEROFILL,
 114                            SectionKind::getBSS());
 115
 116
 117   LazySymbolPointerSection
 118     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
 119                            MCSectionMachO::S_LAZY_SYMBOL_POINTERS,
 120                            SectionKind::getMetadata());
 121   NonLazySymbolPointerSection
 122     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
 123                            MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
 124                            SectionKind::getMetadata());
 125
 126   if (RelocM == Reloc::Static) {
 127     StaticCtorSection
 128       = Ctx->getMachOSection("__TEXT", "__constructor", 0,
 129                              SectionKind::getDataRel());
 130     StaticDtorSection
 131       = Ctx->getMachOSection("__TEXT", "__destructor", 0,
 132                              SectionKind::getDataRel());
 133   } else {
 134     StaticCtorSection
 135       = Ctx->getMachOSection("__DATA", "__mod_init_func",
 136                              MCSectionMachO::S_MOD_INIT_FUNC_POINTERS,
 137                              SectionKind::getDataRel());
 138     StaticDtorSection
 139       = Ctx->getMachOSection("__DATA", "__mod_term_func",
 140                              MCSectionMachO::S_MOD_TERM_FUNC_POINTERS,
 141                              SectionKind::getDataRel());
 142   }
 143
 144   // Exception Handling.
 145   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
 146                                      SectionKind::getReadOnlyWithRel());
 147
 148   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) {
 149     CompactUnwindSection =
 150       Ctx->getMachOSection("__LD", "__compact_unwind",
 151                            MCSectionMachO::S_ATTR_DEBUG,
 152                            SectionKind::getReadOnly());
 153
 154     if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)
 155       CompactUnwindDwarfEHFrameOnly = 0x04000000;
 156   }
 157
 158   // Debug Information.
 159   DwarfAccelNamesSection =
 160     Ctx->getMachOSection("__DWARF", "__apple_names",
 161                          MCSectionMachO::S_ATTR_DEBUG,
 162                          SectionKind::getMetadata());
 163   DwarfAccelObjCSection =
 164     Ctx->getMachOSection("__DWARF", "__apple_objc",
 165                          MCSectionMachO::S_ATTR_DEBUG,
 166                          SectionKind::getMetadata());
 167   // 16 character section limit...
 168   DwarfAccelNamespaceSection =
 169     Ctx->getMachOSection("__DWARF", "__apple_namespac",
 170                          MCSectionMachO::S_ATTR_DEBUG,
 171                          SectionKind::getMetadata());
 172   DwarfAccelTypesSection =
 173     Ctx->getMachOSection("__DWARF", "__apple_types",
 174                          MCSectionMachO::S_ATTR_DEBUG,
 175                          SectionKind::getMetadata());
 176
 177   DwarfAbbrevSection =
 178     Ctx->getMachOSection("__DWARF", "__debug_abbrev",
 179                          MCSectionMachO::S_ATTR_DEBUG,
 180                          SectionKind::getMetadata());
 181   DwarfInfoSection =
 182     Ctx->getMachOSection("__DWARF", "__debug_info",
 183                          MCSectionMachO::S_ATTR_DEBUG,
 184                          SectionKind::getMetadata());
 185   DwarfLineSection =
 186     Ctx->getMachOSection("__DWARF", "__debug_line",
 187                          MCSectionMachO::S_ATTR_DEBUG,
 188                          SectionKind::getMetadata());
 189   DwarfFrameSection =
 190     Ctx->getMachOSection("__DWARF", "__debug_frame",
 191                          MCSectionMachO::S_ATTR_DEBUG,
 192                          SectionKind::getMetadata());
 193   DwarfPubNamesSection =
 194     Ctx->getMachOSection("__DWARF", "__debug_pubnames",
 195                          MCSectionMachO::S_ATTR_DEBUG,
 196                          SectionKind::getMetadata());
 197   DwarfPubTypesSection =
 198     Ctx->getMachOSection("__DWARF", "__debug_pubtypes",
 199                          MCSectionMachO::S_ATTR_DEBUG,
 200                          SectionKind::getMetadata());
 201   DwarfStrSection =
 202     Ctx->getMachOSection("__DWARF", "__debug_str",
 203                          MCSectionMachO::S_ATTR_DEBUG,
 204                          SectionKind::getMetadata());
 205   DwarfLocSection =
 206     Ctx->getMachOSection("__DWARF", "__debug_loc",
 207                          MCSectionMachO::S_ATTR_DEBUG,
 208                          SectionKind::getMetadata());
 209   DwarfARangesSection =
 210     Ctx->getMachOSection("__DWARF", "__debug_aranges",
 211                          MCSectionMachO::S_ATTR_DEBUG,
 212                          SectionKind::getMetadata());
 213   DwarfRangesSection =
 214     Ctx->getMachOSection("__DWARF", "__debug_ranges",
 215                          MCSectionMachO::S_ATTR_DEBUG,
 216                          SectionKind::getMetadata());
 217   DwarfMacroInfoSection =
 218     Ctx->getMachOSection("__DWARF", "__debug_macinfo",
 219                          MCSectionMachO::S_ATTR_DEBUG,
 220                          SectionKind::getMetadata());
 221   DwarfDebugInlineSection =
 222     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 223                          MCSectionMachO::S_ATTR_DEBUG,
 224                          SectionKind::getMetadata());
 225
 226   TLSExtraDataSection = TLSTLVSection;
 227 }
 228
 229 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 230   if (T.getArch() == Triple::mips ||
 231       T.getArch() == Triple::mipsel)
 232     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
 233   else if (T.getArch() == Triple::mips64 ||
 234            T.getArch() == Triple::mips64el)
 235     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
 236   else
 237     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 238
 239   if (T.getArch() == Triple::x86) {
 240     PersonalityEncoding = (RelocM == Reloc::PIC_)
 241      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 242      : dwarf::DW_EH_PE_absptr;
 243     LSDAEncoding = (RelocM == Reloc::PIC_)
 244       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 245       : dwarf::DW_EH_PE_absptr;
 246     FDEEncoding = (RelocM == Reloc::PIC_)
 247       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 248       : dwarf::DW_EH_PE_absptr;
 249     TTypeEncoding = (RelocM == Reloc::PIC_)
 250      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 251      : dwarf::DW_EH_PE_absptr;
 252   } else if (T.getArch() == Triple::x86_64) {
 253     if (RelocM == Reloc::PIC_) {
 254       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 255         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 256          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 257       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 258         (CMModel == CodeModel::Small
 259          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 260       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 261       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 262         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 263          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 264     } else {
 265       PersonalityEncoding =
 266         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 267         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 268       LSDAEncoding = (CMModel == CodeModel::Small)
 269         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 270       FDEEncoding = dwarf::DW_EH_PE_udata4;
 271       TTypeEncoding = (CMModel == CodeModel::Small)
 272         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 273     }
 274   }  else if (T.getArch() ==  Triple::aarch64) {
 275     // The small model guarantees static code/data size < 4GB, but not where it
 276     // will be in memory. Most of these could end up >2GB away so even a signed
 277     // pc-relative 32-bit address is insufficient, theoretically.
 278     if (RelocM == Reloc::PIC_) {
 279       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 280         dwarf::DW_EH_PE_sdata8;
 281       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
 282       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 283       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 284         dwarf::DW_EH_PE_sdata8;
 285     } else {
 286       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 287       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 288       FDEEncoding = dwarf::DW_EH_PE_udata4;
 289       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 290     }
 291   } else if (T.getArch() == Triple::ppc64) {
 292     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 293       dwarf::DW_EH_PE_udata8;
 294     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 295     FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 296     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 297       dwarf::DW_EH_PE_udata8;
 298   } else if (T.getArch() == Triple::systemz) {
 299     // All currently-defined code models guarantee that 4-byte PC-relative
 300     // values will be in range.
 301     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 302       dwarf::DW_EH_PE_sdata4;
 303     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 304     FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 305     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 306       dwarf::DW_EH_PE_sdata4;
 307   }
 308
 309   // Solaris requires different flags for .eh_frame to seemingly every other
 310   // platform.
 311   EHSectionType = ELF::SHT_PROGBITS;
 312   EHSectionFlags = ELF::SHF_ALLOC;
 313   if (T.getOS() == Triple::Solaris) {
 314     if (T.getArch() == Triple::x86_64)
 315       EHSectionType = ELF::SHT_X86_64_UNWIND;
 316     else
 317       EHSectionFlags |= ELF::SHF_WRITE;
 318   }
 319
 320
 321   // ELF
 322   BSSSection =
 323     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 324                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 325                        SectionKind::getBSS());
 326
 327   TextSection =
 328     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 329                        ELF::SHF_EXECINSTR |
 330                        ELF::SHF_ALLOC,
 331                        SectionKind::getText());
 332
 333   DataSection =
 334     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 335                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 336                        SectionKind::getDataRel());
 337
 338   ReadOnlySection =
 339     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 340                        ELF::SHF_ALLOC,
 341                        SectionKind::getReadOnly());
 342
 343   TLSDataSection =
 344     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 345                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 346                        ELF::SHF_WRITE,
 347                        SectionKind::getThreadData());
 348
 349   TLSBSSSection =
 350     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 351                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 352                        ELF::SHF_WRITE,
 353                        SectionKind::getThreadBSS());
 354
 355   DataRelSection =
 356     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 357                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 358                        SectionKind::getDataRel());
 359
 360   DataRelLocalSection =
 361     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 362                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 363                        SectionKind::getDataRelLocal());
 364
 365   DataRelROSection =
 366     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 367                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 368                        SectionKind::getReadOnlyWithRel());
 369
 370   DataRelROLocalSection =
 371     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 372                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 373                        SectionKind::getReadOnlyWithRelLocal());
 374
 375   MergeableConst4Section =
 376     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 377                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 378                        SectionKind::getMergeableConst4());
 379
 380   MergeableConst8Section =
 381     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 382                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 383                        SectionKind::getMergeableConst8());
 384
 385   MergeableConst16Section =
 386     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 387                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 388                        SectionKind::getMergeableConst16());
 389
 390   StaticCtorSection =
 391     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 392                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 393                        SectionKind::getDataRel());
 394
 395   StaticDtorSection =
 396     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 397                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 398                        SectionKind::getDataRel());
 399
 400   // Exception Handling Sections.
 401
 402   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 403   // it contains relocatable pointers.  In PIC mode, this is probably a big
 404   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 405   // adjusted or this should be a data section.
 406   LSDASection =
 407     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 408                        ELF::SHF_ALLOC,
 409                        SectionKind::getReadOnly());
 410
 411   // Debug Info Sections.
 412   DwarfAbbrevSection =
 413     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 414                        SectionKind::getMetadata());
 415   DwarfInfoSection =
 416     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 417                        SectionKind::getMetadata());
 418   DwarfLineSection =
 419     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 420                        SectionKind::getMetadata());
 421   DwarfFrameSection =
 422     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 423                        SectionKind::getMetadata());
 424   DwarfPubNamesSection =
 425     Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0,
 426                        SectionKind::getMetadata());
 427   DwarfPubTypesSection =
 428     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 429                        SectionKind::getMetadata());
 430   DwarfStrSection =
 431     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 432                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 433                        SectionKind::getMergeable1ByteCString());
 434   DwarfLocSection =
 435     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 436                        SectionKind::getMetadata());
 437   DwarfARangesSection =
 438     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 439                        SectionKind::getMetadata());
 440   DwarfRangesSection =
 441     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 442                        SectionKind::getMetadata());
 443   DwarfMacroInfoSection =
 444     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 445                        SectionKind::getMetadata());
 446
 447   // DWARF5 Experimental Debug Info
 448
 449   // Accelerator Tables
 450   DwarfAccelNamesSection =
 451     Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0,
 452                        SectionKind::getMetadata());
 453   DwarfAccelObjCSection =
 454     Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0,
 455                        SectionKind::getMetadata());
 456   DwarfAccelNamespaceSection =
 457     Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0,
 458                        SectionKind::getMetadata());
 459   DwarfAccelTypesSection =
 460     Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0,
 461                        SectionKind::getMetadata());
 462
 463   // Fission Sections
 464   DwarfInfoDWOSection =
 465     Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0,
 466                        SectionKind::getMetadata());
 467   DwarfAbbrevDWOSection =
 468     Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0,
 469                        SectionKind::getMetadata());
 470   DwarfStrDWOSection =
 471     Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 472                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 473                        SectionKind::getMergeable1ByteCString());
 474   DwarfLineDWOSection =
 475     Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0,
 476                        SectionKind::getMetadata());
 477   DwarfLocDWOSection =
 478     Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0,
 479                        SectionKind::getMetadata());
 480   DwarfStrOffDWOSection =
 481     Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0,
 482                        SectionKind::getMetadata());
 483   DwarfAddrSection =
 484     Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0,
 485                        SectionKind::getMetadata());
 486 }
 487
 488
 489 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 490   // COFF
 491   TextSection =
 492     Ctx->getCOFFSection(".text",
 493                         COFF::IMAGE_SCN_CNT_CODE |
 494                         COFF::IMAGE_SCN_MEM_EXECUTE |
 495                         COFF::IMAGE_SCN_MEM_READ,
 496                         SectionKind::getText());
 497   DataSection =
 498     Ctx->getCOFFSection(".data",
 499                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 500                         COFF::IMAGE_SCN_MEM_READ |
 501                         COFF::IMAGE_SCN_MEM_WRITE,
 502                         SectionKind::getDataRel());
 503   ReadOnlySection =
 504     Ctx->getCOFFSection(".rdata",
 505                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 506                         COFF::IMAGE_SCN_MEM_READ,
 507                         SectionKind::getReadOnly());
 508   if (T.getOS() == Triple::Win32) {
 509     StaticCtorSection =
 510       Ctx->getCOFFSection(".CRT$XCU",
 511                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 512                           COFF::IMAGE_SCN_MEM_READ,
 513                           SectionKind::getReadOnly());
 514   } else {
 515     StaticCtorSection =
 516       Ctx->getCOFFSection(".ctors",
 517                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 518                           COFF::IMAGE_SCN_MEM_READ |
 519                           COFF::IMAGE_SCN_MEM_WRITE,
 520                           SectionKind::getDataRel());
 521   }
 522
 523
 524   if (T.getOS() == Triple::Win32) {
 525     StaticDtorSection =
 526       Ctx->getCOFFSection(".CRT$XTX",
 527                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 528                           COFF::IMAGE_SCN_MEM_READ,
 529                           SectionKind::getReadOnly());
 530   } else {
 531     StaticDtorSection =
 532       Ctx->getCOFFSection(".dtors",
 533                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 534                           COFF::IMAGE_SCN_MEM_READ |
 535                           COFF::IMAGE_SCN_MEM_WRITE,
 536                           SectionKind::getDataRel());
 537   }
 538
 539   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 540   // though it contains relocatable pointers.  In PIC mode, this is probably a
 541   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 542   // adjusted or this should be a data section.
 543   LSDASection =
 544     Ctx->getCOFFSection(".gcc_except_table",
 545                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 546                         COFF::IMAGE_SCN_MEM_READ,
 547                         SectionKind::getReadOnly());
 548
 549   // Debug info.
 550   DwarfAbbrevSection =
 551     Ctx->getCOFFSection(".debug_abbrev",
 552                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 553                         COFF::IMAGE_SCN_MEM_READ,
 554                         SectionKind::getMetadata());
 555   DwarfInfoSection =
 556     Ctx->getCOFFSection(".debug_info",
 557                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 558                         COFF::IMAGE_SCN_MEM_READ,
 559                         SectionKind::getMetadata());
 560   DwarfLineSection =
 561     Ctx->getCOFFSection(".debug_line",
 562                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 563                         COFF::IMAGE_SCN_MEM_READ,
 564                         SectionKind::getMetadata());
 565   DwarfFrameSection =
 566     Ctx->getCOFFSection(".debug_frame",
 567                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 568                         COFF::IMAGE_SCN_MEM_READ,
 569                         SectionKind::getMetadata());
 570   DwarfPubNamesSection =
 571     Ctx->getCOFFSection(".debug_pubnames",
 572                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 573                         COFF::IMAGE_SCN_MEM_READ,
 574                         SectionKind::getMetadata());
 575   DwarfPubTypesSection =
 576     Ctx->getCOFFSection(".debug_pubtypes",
 577                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 578                         COFF::IMAGE_SCN_MEM_READ,
 579                         SectionKind::getMetadata());
 580   DwarfStrSection =
 581     Ctx->getCOFFSection(".debug_str",
 582                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 583                         COFF::IMAGE_SCN_MEM_READ,
 584                         SectionKind::getMetadata());
 585   DwarfLocSection =
 586     Ctx->getCOFFSection(".debug_loc",
 587                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 588                         COFF::IMAGE_SCN_MEM_READ,
 589                         SectionKind::getMetadata());
 590   DwarfARangesSection =
 591     Ctx->getCOFFSection(".debug_aranges",
 592                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 593                         COFF::IMAGE_SCN_MEM_READ,
 594                         SectionKind::getMetadata());
 595   DwarfRangesSection =
 596     Ctx->getCOFFSection(".debug_ranges",
 597                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 598                         COFF::IMAGE_SCN_MEM_READ,
 599                         SectionKind::getMetadata());
 600   DwarfMacroInfoSection =
 601     Ctx->getCOFFSection(".debug_macinfo",
 602                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 603                         COFF::IMAGE_SCN_MEM_READ,
 604                         SectionKind::getMetadata());
 605
 606   DrectveSection =
 607     Ctx->getCOFFSection(".drectve",
 608                         COFF::IMAGE_SCN_LNK_INFO,
 609                         SectionKind::getMetadata());
 610
 611   PDataSection =
 612     Ctx->getCOFFSection(".pdata",
 613                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 614                         COFF::IMAGE_SCN_MEM_READ,
 615                         SectionKind::getDataRel());
 616
 617   XDataSection =
 618     Ctx->getCOFFSection(".xdata",
 619                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 620                         COFF::IMAGE_SCN_MEM_READ,
 621                         SectionKind::getDataRel());
 622   TLSDataSection =
 623     Ctx->getCOFFSection(".tls$",
 624                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 625                         COFF::IMAGE_SCN_MEM_READ |
 626                         COFF::IMAGE_SCN_MEM_WRITE,
 627                         SectionKind::getDataRel());
 628 }
 629
 630 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
 631                                             CodeModel::Model cm,
 632                                             MCContext &ctx) {
 633   RelocM = relocm;
 634   CMModel = cm;
 635   Ctx = &ctx;
 636
 637   // Common.
 638   CommDirectiveSupportsAlignment = true;
 639   SupportsWeakOmittedEHFrame = true;
 640   IsFunctionEHFrameSymbolPrivate = true;
 641
 642   PersonalityEncoding = LSDAEncoding = FDEEncoding = FDECFIEncoding =
 643     TTypeEncoding = dwarf::DW_EH_PE_absptr;
 644
 645   CompactUnwindDwarfEHFrameOnly = 0;
 646
 647   EHFrameSection = 0;             // Created on demand.
 648   CompactUnwindSection = 0;       // Used only by selected targets.
 649   DwarfAccelNamesSection = 0;     // Used only by selected targets.
 650   DwarfAccelObjCSection = 0;      // Used only by selected targets.
 651   DwarfAccelNamespaceSection = 0; // Used only by selected targets.
 652   DwarfAccelTypesSection = 0;     // Used only by selected targets.
 653
 654   Triple T(TT);
 655   Triple::ArchType Arch = T.getArch();
 656   // FIXME: Checking for Arch here to filter out bogus triples such as
 657   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 658   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 659        Arch == Triple::arm || Arch == Triple::thumb ||
 660        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 661        Arch == Triple::UnknownArch) &&
 662       (T.isOSDarwin() || T.getEnvironment() == Triple::MachO)) {
 663     Env = IsMachO;
 664     InitMachOMCObjectFileInfo(T);
 665   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64) &&
 666              (T.getEnvironment() != Triple::ELF) &&
 667              (T.getOS() == Triple::MinGW32 || T.getOS() == Triple::Cygwin ||
 668               T.getOS() == Triple::Win32)) {
 669     Env = IsCOFF;
 670     InitCOFFMCObjectFileInfo(T);
 671   } else {
 672     Env = IsELF;
 673     InitELFMCObjectFileInfo(T);
 674   }
 675 }
 676
 677 void MCObjectFileInfo::InitEHFrameSection() {
 678   if (Env == IsMachO)
 679     EHFrameSection =
 680       Ctx->getMachOSection("__TEXT", "__eh_frame",
 681                            MCSectionMachO::S_COALESCED |
 682                            MCSectionMachO::S_ATTR_NO_TOC |
 683                            MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
 684                            MCSectionMachO::S_ATTR_LIVE_SUPPORT,
 685                            SectionKind::getReadOnly());
 686   else if (Env == IsELF)
 687     EHFrameSection =
 688       Ctx->getELFSection(".eh_frame", EHSectionType,
 689                          EHSectionFlags,
 690                          SectionKind::getDataRel());
 691   else
 692     EHFrameSection =
 693       Ctx->getCOFFSection(".eh_frame",
 694                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 695                           COFF::IMAGE_SCN_MEM_READ |
 696                           COFF::IMAGE_SCN_MEM_WRITE,
 697                           SectionKind::getDataRel());
 698 }