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/MC/MCContext.h"
  12 #include "llvm/MC/MCSection.h"
  13 #include "llvm/MC/MCSectionCOFF.h"
  14 #include "llvm/MC/MCSectionELF.h"
  15 #include "llvm/MC/MCSectionMachO.h"
  16 #include "llvm/ADT/Triple.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   // Debug Information.
 155   DwarfAccelNamesSection =
 156     Ctx->getMachOSection("__DWARF", "__apple_names",
 157                          MCSectionMachO::S_ATTR_DEBUG,
 158                          SectionKind::getMetadata());
 159   DwarfAccelObjCSection =
 160     Ctx->getMachOSection("__DWARF", "__apple_objc",
 161                          MCSectionMachO::S_ATTR_DEBUG,
 162                          SectionKind::getMetadata());
 163   // 16 character section limit...
 164   DwarfAccelNamespaceSection =
 165     Ctx->getMachOSection("__DWARF", "__apple_namespac",
 166                          MCSectionMachO::S_ATTR_DEBUG,
 167                          SectionKind::getMetadata());
 168   DwarfAccelTypesSection =
 169     Ctx->getMachOSection("__DWARF", "__apple_types",
 170                          MCSectionMachO::S_ATTR_DEBUG,
 171                          SectionKind::getMetadata());
 172
 173   DwarfAbbrevSection =
 174     Ctx->getMachOSection("__DWARF", "__debug_abbrev",
 175                          MCSectionMachO::S_ATTR_DEBUG,
 176                          SectionKind::getMetadata());
 177   DwarfInfoSection =
 178     Ctx->getMachOSection("__DWARF", "__debug_info",
 179                          MCSectionMachO::S_ATTR_DEBUG,
 180                          SectionKind::getMetadata());
 181   DwarfLineSection =
 182     Ctx->getMachOSection("__DWARF", "__debug_line",
 183                          MCSectionMachO::S_ATTR_DEBUG,
 184                          SectionKind::getMetadata());
 185   DwarfFrameSection =
 186     Ctx->getMachOSection("__DWARF", "__debug_frame",
 187                          MCSectionMachO::S_ATTR_DEBUG,
 188                          SectionKind::getMetadata());
 189   DwarfPubTypesSection =
 190     Ctx->getMachOSection("__DWARF", "__debug_pubtypes",
 191                          MCSectionMachO::S_ATTR_DEBUG,
 192                          SectionKind::getMetadata());
 193   DwarfStrSection =
 194     Ctx->getMachOSection("__DWARF", "__debug_str",
 195                          MCSectionMachO::S_ATTR_DEBUG,
 196                          SectionKind::getMetadata());
 197   DwarfLocSection =
 198     Ctx->getMachOSection("__DWARF", "__debug_loc",
 199                          MCSectionMachO::S_ATTR_DEBUG,
 200                          SectionKind::getMetadata());
 201   DwarfARangesSection =
 202     Ctx->getMachOSection("__DWARF", "__debug_aranges",
 203                          MCSectionMachO::S_ATTR_DEBUG,
 204                          SectionKind::getMetadata());
 205   DwarfRangesSection =
 206     Ctx->getMachOSection("__DWARF", "__debug_ranges",
 207                          MCSectionMachO::S_ATTR_DEBUG,
 208                          SectionKind::getMetadata());
 209   DwarfMacroInfoSection =
 210     Ctx->getMachOSection("__DWARF", "__debug_macinfo",
 211                          MCSectionMachO::S_ATTR_DEBUG,
 212                          SectionKind::getMetadata());
 213   DwarfDebugInlineSection =
 214     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 215                          MCSectionMachO::S_ATTR_DEBUG,
 216                          SectionKind::getMetadata());
 217
 218   TLSExtraDataSection = TLSTLVSection;
 219 }
 220
 221 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 222   if (T.getArch() == Triple::x86) {
 223     PersonalityEncoding = (RelocM == Reloc::PIC_)
 224      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 225      : dwarf::DW_EH_PE_absptr;
 226     LSDAEncoding = (RelocM == Reloc::PIC_)
 227       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 228       : dwarf::DW_EH_PE_absptr;
 229     FDEEncoding = FDECFIEncoding = (RelocM == Reloc::PIC_)
 230       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 231       : dwarf::DW_EH_PE_absptr;
 232     TTypeEncoding = (RelocM == Reloc::PIC_)
 233      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 234      : dwarf::DW_EH_PE_absptr;
 235   } else if (T.getArch() == Triple::x86_64) {
 236     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 237
 238     if (RelocM == Reloc::PIC_) {
 239       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 240         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 241          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 242       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 243         (CMModel == CodeModel::Small
 244          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 245       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 246       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 247         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 248          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 249     } else {
 250       PersonalityEncoding =
 251         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 252         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 253       LSDAEncoding = (CMModel == CodeModel::Small)
 254         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 255       FDEEncoding = dwarf::DW_EH_PE_udata4;
 256       TTypeEncoding = (CMModel == CodeModel::Small)
 257         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 258     }
 259   }
 260
 261   // ELF
 262   BSSSection =
 263     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 264                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 265                        SectionKind::getBSS());
 266
 267   TextSection =
 268     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 269                        ELF::SHF_EXECINSTR |
 270                        ELF::SHF_ALLOC,
 271                        SectionKind::getText());
 272
 273   DataSection =
 274     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 275                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 276                        SectionKind::getDataRel());
 277
 278   ReadOnlySection =
 279     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 280                        ELF::SHF_ALLOC,
 281                        SectionKind::getReadOnly());
 282
 283   TLSDataSection =
 284     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 285                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 286                        ELF::SHF_WRITE,
 287                        SectionKind::getThreadData());
 288
 289   TLSBSSSection =
 290     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 291                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 292                        ELF::SHF_WRITE,
 293                        SectionKind::getThreadBSS());
 294
 295   DataRelSection =
 296     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 297                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 298                        SectionKind::getDataRel());
 299
 300   DataRelLocalSection =
 301     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 302                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 303                        SectionKind::getDataRelLocal());
 304
 305   DataRelROSection =
 306     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 307                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 308                        SectionKind::getReadOnlyWithRel());
 309
 310   DataRelROLocalSection =
 311     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 312                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 313                        SectionKind::getReadOnlyWithRelLocal());
 314
 315   MergeableConst4Section =
 316     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 317                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 318                        SectionKind::getMergeableConst4());
 319
 320   MergeableConst8Section =
 321     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 322                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 323                        SectionKind::getMergeableConst8());
 324
 325   MergeableConst16Section =
 326     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 327                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 328                        SectionKind::getMergeableConst16());
 329
 330   StaticCtorSection =
 331     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 332                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 333                        SectionKind::getDataRel());
 334
 335   StaticDtorSection =
 336     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 337                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 338                        SectionKind::getDataRel());
 339
 340   // Exception Handling Sections.
 341
 342   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 343   // it contains relocatable pointers.  In PIC mode, this is probably a big
 344   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 345   // adjusted or this should be a data section.
 346   LSDASection =
 347     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 348                        ELF::SHF_ALLOC,
 349                        SectionKind::getReadOnly());
 350
 351   // Debug Info Sections.
 352   DwarfAbbrevSection =
 353     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 354                        SectionKind::getMetadata());
 355   DwarfInfoSection =
 356     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 357                        SectionKind::getMetadata());
 358   DwarfLineSection =
 359     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 360                        SectionKind::getMetadata());
 361   DwarfFrameSection =
 362     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 363                        SectionKind::getMetadata());
 364   DwarfPubTypesSection =
 365     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 366                        SectionKind::getMetadata());
 367   DwarfStrSection =
 368     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 369                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 370                        SectionKind::getMergeable1ByteCString());
 371   DwarfLocSection =
 372     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 373                        SectionKind::getMetadata());
 374   DwarfARangesSection =
 375     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 376                        SectionKind::getMetadata());
 377   DwarfRangesSection =
 378     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 379                        SectionKind::getMetadata());
 380   DwarfMacroInfoSection =
 381     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 382                        SectionKind::getMetadata());
 383 }
 384
 385
 386 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 387   // COFF
 388   TextSection =
 389     Ctx->getCOFFSection(".text",
 390                         COFF::IMAGE_SCN_CNT_CODE |
 391                         COFF::IMAGE_SCN_MEM_EXECUTE |
 392                         COFF::IMAGE_SCN_MEM_READ,
 393                         SectionKind::getText());
 394   DataSection =
 395     Ctx->getCOFFSection(".data",
 396                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 397                         COFF::IMAGE_SCN_MEM_READ |
 398                         COFF::IMAGE_SCN_MEM_WRITE,
 399                         SectionKind::getDataRel());
 400   ReadOnlySection =
 401     Ctx->getCOFFSection(".rdata",
 402                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 403                         COFF::IMAGE_SCN_MEM_READ,
 404                         SectionKind::getReadOnly());
 405   StaticCtorSection =
 406     Ctx->getCOFFSection(".ctors",
 407                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 408                         COFF::IMAGE_SCN_MEM_READ |
 409                         COFF::IMAGE_SCN_MEM_WRITE,
 410                         SectionKind::getDataRel());
 411   StaticDtorSection =
 412     Ctx->getCOFFSection(".dtors",
 413                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 414                         COFF::IMAGE_SCN_MEM_READ |
 415                         COFF::IMAGE_SCN_MEM_WRITE,
 416                         SectionKind::getDataRel());
 417
 418   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 419   // though it contains relocatable pointers.  In PIC mode, this is probably a
 420   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 421   // adjusted or this should be a data section.
 422   LSDASection =
 423     Ctx->getCOFFSection(".gcc_except_table",
 424                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 425                         COFF::IMAGE_SCN_MEM_READ,
 426                         SectionKind::getReadOnly());
 427
 428   // Debug info.
 429   DwarfAbbrevSection =
 430     Ctx->getCOFFSection(".debug_abbrev",
 431                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 432                         COFF::IMAGE_SCN_MEM_READ,
 433                         SectionKind::getMetadata());
 434   DwarfInfoSection =
 435     Ctx->getCOFFSection(".debug_info",
 436                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 437                         COFF::IMAGE_SCN_MEM_READ,
 438                         SectionKind::getMetadata());
 439   DwarfLineSection =
 440     Ctx->getCOFFSection(".debug_line",
 441                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 442                         COFF::IMAGE_SCN_MEM_READ,
 443                         SectionKind::getMetadata());
 444   DwarfFrameSection =
 445     Ctx->getCOFFSection(".debug_frame",
 446                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 447                         COFF::IMAGE_SCN_MEM_READ,
 448                         SectionKind::getMetadata());
 449   DwarfPubTypesSection =
 450     Ctx->getCOFFSection(".debug_pubtypes",
 451                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 452                         COFF::IMAGE_SCN_MEM_READ,
 453                         SectionKind::getMetadata());
 454   DwarfStrSection =
 455     Ctx->getCOFFSection(".debug_str",
 456                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 457                         COFF::IMAGE_SCN_MEM_READ,
 458                         SectionKind::getMetadata());
 459   DwarfLocSection =
 460     Ctx->getCOFFSection(".debug_loc",
 461                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 462                         COFF::IMAGE_SCN_MEM_READ,
 463                         SectionKind::getMetadata());
 464   DwarfARangesSection =
 465     Ctx->getCOFFSection(".debug_aranges",
 466                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 467                         COFF::IMAGE_SCN_MEM_READ,
 468                         SectionKind::getMetadata());
 469   DwarfRangesSection =
 470     Ctx->getCOFFSection(".debug_ranges",
 471                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 472                         COFF::IMAGE_SCN_MEM_READ,
 473                         SectionKind::getMetadata());
 474   DwarfMacroInfoSection =
 475     Ctx->getCOFFSection(".debug_macinfo",
 476                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 477                         COFF::IMAGE_SCN_MEM_READ,
 478                         SectionKind::getMetadata());
 479
 480   DrectveSection =
 481     Ctx->getCOFFSection(".drectve",
 482                         COFF::IMAGE_SCN_LNK_INFO,
 483                         SectionKind::getMetadata());
 484
 485   PDataSection =
 486     Ctx->getCOFFSection(".pdata",
 487                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 488                         COFF::IMAGE_SCN_MEM_READ |
 489                         COFF::IMAGE_SCN_MEM_WRITE,
 490                         SectionKind::getDataRel());
 491
 492   XDataSection =
 493     Ctx->getCOFFSection(".xdata",
 494                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 495                         COFF::IMAGE_SCN_MEM_READ |
 496                         COFF::IMAGE_SCN_MEM_WRITE,
 497                         SectionKind::getDataRel());
 498 }
 499
 500 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
 501                                             CodeModel::Model cm,
 502                                             MCContext &ctx) {
 503   RelocM = relocm;
 504   CMModel = cm;
 505   Ctx = &ctx;
 506
 507   // Common.
 508   CommDirectiveSupportsAlignment = true;
 509   SupportsWeakOmittedEHFrame = true;
 510   IsFunctionEHFrameSymbolPrivate = true;
 511
 512   PersonalityEncoding = LSDAEncoding = FDEEncoding = FDECFIEncoding =
 513     TTypeEncoding = dwarf::DW_EH_PE_absptr;
 514
 515   EHFrameSection = 0;             // Created on demand.
 516   CompactUnwindSection = 0;       // Used only by selected targets.
 517   DwarfAccelNamesSection = 0;     // Used only by selected targets.
 518   DwarfAccelObjCSection = 0;      // Used only by selected targets.
 519   DwarfAccelNamespaceSection = 0; // Used only by selected targets.
 520   DwarfAccelTypesSection = 0;     // Used only by selected targets.
 521
 522   Triple T(TT);
 523   Triple::ArchType Arch = T.getArch();
 524   // FIXME: Checking for Arch here to filter out bogus triples such as
 525   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 526   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 527        Arch == Triple::arm || Arch == Triple::thumb ||
 528        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 529        Arch == Triple::UnknownArch) &&
 530       (T.isOSDarwin() || T.getEnvironment() == Triple::MachO)) {
 531     Env = IsMachO;
 532     InitMachOMCObjectFileInfo(T);
 533   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64) &&
 534              (T.getOS() == Triple::MinGW32 || T.getOS() == Triple::Cygwin ||
 535               T.getOS() == Triple::Win32)) {
 536     Env = IsCOFF;
 537     InitCOFFMCObjectFileInfo(T);
 538   } else {
 539     Env = IsELF;
 540     InitELFMCObjectFileInfo(T);
 541   }
 542 }
 543
 544 void MCObjectFileInfo::InitEHFrameSection() {
 545   if (Env == IsMachO)
 546     EHFrameSection =
 547       Ctx->getMachOSection("__TEXT", "__eh_frame",
 548                            MCSectionMachO::S_COALESCED |
 549                            MCSectionMachO::S_ATTR_NO_TOC |
 550                            MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
 551                            MCSectionMachO::S_ATTR_LIVE_SUPPORT,
 552                            SectionKind::getReadOnly());
 553   else if (Env == IsELF)
 554     EHFrameSection =
 555       Ctx->getELFSection(".eh_frame", ELF::SHT_PROGBITS,
 556                          ELF::SHF_ALLOC,
 557                          SectionKind::getDataRel());
 558   else
 559     EHFrameSection =
 560       Ctx->getCOFFSection(".eh_frame",
 561                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 562                           COFF::IMAGE_SCN_MEM_READ |
 563                           COFF::IMAGE_SCN_MEM_WRITE,
 564                           SectionKind::getDataRel());
 565 }