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   // 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   DwarfPubNamesSection =
 190     Ctx->getMachOSection("__DWARF", "__debug_pubnames",
 191                          MCSectionMachO::S_ATTR_DEBUG,
 192                          SectionKind::getMetadata());
 193   DwarfPubTypesSection =
 194     Ctx->getMachOSection("__DWARF", "__debug_pubtypes",
 195                          MCSectionMachO::S_ATTR_DEBUG,
 196                          SectionKind::getMetadata());
 197   DwarfStrSection =
 198     Ctx->getMachOSection("__DWARF", "__debug_str",
 199                          MCSectionMachO::S_ATTR_DEBUG,
 200                          SectionKind::getMetadata());
 201   DwarfLocSection =
 202     Ctx->getMachOSection("__DWARF", "__debug_loc",
 203                          MCSectionMachO::S_ATTR_DEBUG,
 204                          SectionKind::getMetadata());
 205   DwarfARangesSection =
 206     Ctx->getMachOSection("__DWARF", "__debug_aranges",
 207                          MCSectionMachO::S_ATTR_DEBUG,
 208                          SectionKind::getMetadata());
 209   DwarfRangesSection =
 210     Ctx->getMachOSection("__DWARF", "__debug_ranges",
 211                          MCSectionMachO::S_ATTR_DEBUG,
 212                          SectionKind::getMetadata());
 213   DwarfMacroInfoSection =
 214     Ctx->getMachOSection("__DWARF", "__debug_macinfo",
 215                          MCSectionMachO::S_ATTR_DEBUG,
 216                          SectionKind::getMetadata());
 217   DwarfDebugInlineSection =
 218     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 219                          MCSectionMachO::S_ATTR_DEBUG,
 220                          SectionKind::getMetadata());
 221
 222   TLSExtraDataSection = TLSTLVSection;
 223 }
 224
 225 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 226   if (T.getArch() != Triple::mips &&
 227       T.getArch() != Triple::mipsel &&
 228       T.getArch() != Triple::mips64 &&
 229       T.getArch() != Triple::mips64el )
 230     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 231
 232   if (T.getArch() == Triple::x86) {
 233     PersonalityEncoding = (RelocM == Reloc::PIC_)
 234      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 235      : dwarf::DW_EH_PE_absptr;
 236     LSDAEncoding = (RelocM == Reloc::PIC_)
 237       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 238       : dwarf::DW_EH_PE_absptr;
 239     FDEEncoding = (RelocM == Reloc::PIC_)
 240       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 241       : dwarf::DW_EH_PE_absptr;
 242     TTypeEncoding = (RelocM == Reloc::PIC_)
 243      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 244      : dwarf::DW_EH_PE_absptr;
 245   } else if (T.getArch() == Triple::x86_64) {
 246     if (RelocM == Reloc::PIC_) {
 247       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 248         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 249          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 250       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 251         (CMModel == CodeModel::Small
 252          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 253       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 254       TTypeEncoding = 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     } else {
 258       PersonalityEncoding =
 259         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 260         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 261       LSDAEncoding = (CMModel == CodeModel::Small)
 262         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 263       FDEEncoding = dwarf::DW_EH_PE_udata4;
 264       TTypeEncoding = (CMModel == CodeModel::Small)
 265         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 266     }
 267   }  else if (T.getArch() ==  Triple::aarch64) {
 268     // The small model guarantees static code/data size < 4GB, but not where it
 269     // will be in memory. Most of these could end up >2GB away so even a signed
 270     // pc-relative 32-bit address is insufficient, theoretically.
 271     if (RelocM == Reloc::PIC_) {
 272       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 273         dwarf::DW_EH_PE_sdata8;
 274       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
 275       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 276       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 277         dwarf::DW_EH_PE_sdata8;
 278     } else {
 279       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 280       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 281       FDEEncoding = dwarf::DW_EH_PE_udata4;
 282       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 283     }
 284   } else if (T.getArch() == Triple::ppc64) {
 285     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 286       dwarf::DW_EH_PE_udata8;
 287     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 288     FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 289     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 290       dwarf::DW_EH_PE_udata8;
 291   }
 292
 293   // Solaris requires different flags for .eh_frame to seemingly every other
 294   // platform.
 295   EHSectionType = ELF::SHT_PROGBITS;
 296   EHSectionFlags = ELF::SHF_ALLOC;
 297   if (T.getOS() == Triple::Solaris) {
 298     if (T.getArch() == Triple::x86_64)
 299       EHSectionType = ELF::SHT_X86_64_UNWIND;
 300     else
 301       EHSectionFlags |= ELF::SHF_WRITE;
 302   }
 303
 304
 305   // ELF
 306   BSSSection =
 307     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 308                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 309                        SectionKind::getBSS());
 310
 311   TextSection =
 312     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 313                        ELF::SHF_EXECINSTR |
 314                        ELF::SHF_ALLOC,
 315                        SectionKind::getText());
 316
 317   DataSection =
 318     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 319                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 320                        SectionKind::getDataRel());
 321
 322   ReadOnlySection =
 323     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 324                        ELF::SHF_ALLOC,
 325                        SectionKind::getReadOnly());
 326
 327   TLSDataSection =
 328     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 329                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 330                        ELF::SHF_WRITE,
 331                        SectionKind::getThreadData());
 332
 333   TLSBSSSection =
 334     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 335                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 336                        ELF::SHF_WRITE,
 337                        SectionKind::getThreadBSS());
 338
 339   DataRelSection =
 340     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 341                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 342                        SectionKind::getDataRel());
 343
 344   DataRelLocalSection =
 345     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 346                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 347                        SectionKind::getDataRelLocal());
 348
 349   DataRelROSection =
 350     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 351                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 352                        SectionKind::getReadOnlyWithRel());
 353
 354   DataRelROLocalSection =
 355     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 356                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 357                        SectionKind::getReadOnlyWithRelLocal());
 358
 359   MergeableConst4Section =
 360     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 361                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 362                        SectionKind::getMergeableConst4());
 363
 364   MergeableConst8Section =
 365     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 366                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 367                        SectionKind::getMergeableConst8());
 368
 369   MergeableConst16Section =
 370     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 371                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 372                        SectionKind::getMergeableConst16());
 373
 374   StaticCtorSection =
 375     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 376                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 377                        SectionKind::getDataRel());
 378
 379   StaticDtorSection =
 380     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 381                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 382                        SectionKind::getDataRel());
 383
 384   // Exception Handling Sections.
 385
 386   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 387   // it contains relocatable pointers.  In PIC mode, this is probably a big
 388   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 389   // adjusted or this should be a data section.
 390   LSDASection =
 391     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 392                        ELF::SHF_ALLOC,
 393                        SectionKind::getReadOnly());
 394
 395   // Debug Info Sections.
 396   DwarfAbbrevSection =
 397     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 398                        SectionKind::getMetadata());
 399   DwarfInfoSection =
 400     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 401                        SectionKind::getMetadata());
 402   DwarfLineSection =
 403     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 404                        SectionKind::getMetadata());
 405   DwarfFrameSection =
 406     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 407                        SectionKind::getMetadata());
 408   DwarfPubNamesSection =
 409     Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0,
 410                        SectionKind::getMetadata());
 411   DwarfPubTypesSection =
 412     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 413                        SectionKind::getMetadata());
 414   DwarfStrSection =
 415     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 416                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 417                        SectionKind::getMergeable1ByteCString());
 418   DwarfLocSection =
 419     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 420                        SectionKind::getMetadata());
 421   DwarfARangesSection =
 422     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 423                        SectionKind::getMetadata());
 424   DwarfRangesSection =
 425     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 426                        SectionKind::getMetadata());
 427   DwarfMacroInfoSection =
 428     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 429                        SectionKind::getMetadata());
 430
 431   // DWARF5 Experimental Debug Info
 432
 433   // Accelerator Tables
 434   DwarfAccelNamesSection =
 435     Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0,
 436                        SectionKind::getMetadata());
 437   DwarfAccelObjCSection =
 438     Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0,
 439                        SectionKind::getMetadata());
 440   DwarfAccelNamespaceSection =
 441     Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0,
 442                        SectionKind::getMetadata());
 443   DwarfAccelTypesSection =
 444     Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0,
 445                        SectionKind::getMetadata());
 446
 447   // Fission Sections
 448   DwarfInfoDWOSection =
 449     Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0,
 450                        SectionKind::getMetadata());
 451   DwarfAbbrevDWOSection =
 452     Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0,
 453                        SectionKind::getMetadata());
 454   DwarfStrDWOSection =
 455     Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 456                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 457                        SectionKind::getMergeable1ByteCString());
 458   DwarfLineDWOSection =
 459     Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0,
 460                        SectionKind::getMetadata());
 461   DwarfLocDWOSection =
 462     Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0,
 463                        SectionKind::getMetadata());
 464   DwarfStrOffDWOSection =
 465     Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0,
 466                        SectionKind::getMetadata());
 467   DwarfAddrSection =
 468     Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0,
 469                        SectionKind::getMetadata());
 470 }
 471
 472
 473 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 474   // COFF
 475   TextSection =
 476     Ctx->getCOFFSection(".text",
 477                         COFF::IMAGE_SCN_CNT_CODE |
 478                         COFF::IMAGE_SCN_MEM_EXECUTE |
 479                         COFF::IMAGE_SCN_MEM_READ,
 480                         SectionKind::getText());
 481   DataSection =
 482     Ctx->getCOFFSection(".data",
 483                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 484                         COFF::IMAGE_SCN_MEM_READ |
 485                         COFF::IMAGE_SCN_MEM_WRITE,
 486                         SectionKind::getDataRel());
 487   ReadOnlySection =
 488     Ctx->getCOFFSection(".rdata",
 489                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 490                         COFF::IMAGE_SCN_MEM_READ,
 491                         SectionKind::getReadOnly());
 492   if (T.getOS() == Triple::Win32) {
 493     StaticCtorSection =
 494       Ctx->getCOFFSection(".CRT$XCU",
 495                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 496                           COFF::IMAGE_SCN_MEM_READ,
 497                           SectionKind::getReadOnly());
 498   } else {
 499     StaticCtorSection =
 500       Ctx->getCOFFSection(".ctors",
 501                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 502                           COFF::IMAGE_SCN_MEM_READ |
 503                           COFF::IMAGE_SCN_MEM_WRITE,
 504                           SectionKind::getDataRel());
 505   }
 506
 507
 508   if (T.getOS() == Triple::Win32) {
 509     StaticDtorSection =
 510       Ctx->getCOFFSection(".CRT$XTX",
 511                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 512                           COFF::IMAGE_SCN_MEM_READ,
 513                           SectionKind::getReadOnly());
 514   } else {
 515     StaticDtorSection =
 516       Ctx->getCOFFSection(".dtors",
 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   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 524   // though it contains relocatable pointers.  In PIC mode, this is probably a
 525   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 526   // adjusted or this should be a data section.
 527   LSDASection =
 528     Ctx->getCOFFSection(".gcc_except_table",
 529                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 530                         COFF::IMAGE_SCN_MEM_READ,
 531                         SectionKind::getReadOnly());
 532
 533   // Debug info.
 534   DwarfAbbrevSection =
 535     Ctx->getCOFFSection(".debug_abbrev",
 536                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 537                         COFF::IMAGE_SCN_MEM_READ,
 538                         SectionKind::getMetadata());
 539   DwarfInfoSection =
 540     Ctx->getCOFFSection(".debug_info",
 541                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 542                         COFF::IMAGE_SCN_MEM_READ,
 543                         SectionKind::getMetadata());
 544   DwarfLineSection =
 545     Ctx->getCOFFSection(".debug_line",
 546                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 547                         COFF::IMAGE_SCN_MEM_READ,
 548                         SectionKind::getMetadata());
 549   DwarfFrameSection =
 550     Ctx->getCOFFSection(".debug_frame",
 551                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 552                         COFF::IMAGE_SCN_MEM_READ,
 553                         SectionKind::getMetadata());
 554   DwarfPubNamesSection =
 555     Ctx->getCOFFSection(".debug_pubnames",
 556                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 557                         COFF::IMAGE_SCN_MEM_READ,
 558                         SectionKind::getMetadata());
 559   DwarfPubTypesSection =
 560     Ctx->getCOFFSection(".debug_pubtypes",
 561                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 562                         COFF::IMAGE_SCN_MEM_READ,
 563                         SectionKind::getMetadata());
 564   DwarfStrSection =
 565     Ctx->getCOFFSection(".debug_str",
 566                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 567                         COFF::IMAGE_SCN_MEM_READ,
 568                         SectionKind::getMetadata());
 569   DwarfLocSection =
 570     Ctx->getCOFFSection(".debug_loc",
 571                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 572                         COFF::IMAGE_SCN_MEM_READ,
 573                         SectionKind::getMetadata());
 574   DwarfARangesSection =
 575     Ctx->getCOFFSection(".debug_aranges",
 576                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 577                         COFF::IMAGE_SCN_MEM_READ,
 578                         SectionKind::getMetadata());
 579   DwarfRangesSection =
 580     Ctx->getCOFFSection(".debug_ranges",
 581                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 582                         COFF::IMAGE_SCN_MEM_READ,
 583                         SectionKind::getMetadata());
 584   DwarfMacroInfoSection =
 585     Ctx->getCOFFSection(".debug_macinfo",
 586                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 587                         COFF::IMAGE_SCN_MEM_READ,
 588                         SectionKind::getMetadata());
 589
 590   DrectveSection =
 591     Ctx->getCOFFSection(".drectve",
 592                         COFF::IMAGE_SCN_LNK_INFO,
 593                         SectionKind::getMetadata());
 594
 595   PDataSection =
 596     Ctx->getCOFFSection(".pdata",
 597                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 598                         COFF::IMAGE_SCN_MEM_READ,
 599                         SectionKind::getDataRel());
 600
 601   XDataSection =
 602     Ctx->getCOFFSection(".xdata",
 603                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 604                         COFF::IMAGE_SCN_MEM_READ,
 605                         SectionKind::getDataRel());
 606   TLSDataSection =
 607     Ctx->getCOFFSection(".tls$",
 608                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 609                         COFF::IMAGE_SCN_MEM_READ |
 610                         COFF::IMAGE_SCN_MEM_WRITE,
 611                         SectionKind::getDataRel());
 612 }
 613
 614 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
 615                                             CodeModel::Model cm,
 616                                             MCContext &ctx) {
 617   RelocM = relocm;
 618   CMModel = cm;
 619   Ctx = &ctx;
 620
 621   // Common.
 622   CommDirectiveSupportsAlignment = true;
 623   SupportsWeakOmittedEHFrame = true;
 624   IsFunctionEHFrameSymbolPrivate = true;
 625
 626   PersonalityEncoding = LSDAEncoding = FDEEncoding = FDECFIEncoding =
 627     TTypeEncoding = dwarf::DW_EH_PE_absptr;
 628
 629   EHFrameSection = 0;             // Created on demand.
 630   CompactUnwindSection = 0;       // Used only by selected targets.
 631   DwarfAccelNamesSection = 0;     // Used only by selected targets.
 632   DwarfAccelObjCSection = 0;      // Used only by selected targets.
 633   DwarfAccelNamespaceSection = 0; // Used only by selected targets.
 634   DwarfAccelTypesSection = 0;     // Used only by selected targets.
 635
 636   Triple T(TT);
 637   Triple::ArchType Arch = T.getArch();
 638   // FIXME: Checking for Arch here to filter out bogus triples such as
 639   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 640   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 641        Arch == Triple::arm || Arch == Triple::thumb ||
 642        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 643        Arch == Triple::UnknownArch) &&
 644       (T.isOSDarwin() || T.getEnvironment() == Triple::MachO)) {
 645     Env = IsMachO;
 646     InitMachOMCObjectFileInfo(T);
 647   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64) &&
 648              (T.getEnvironment() != Triple::ELF) &&
 649              (T.getOS() == Triple::MinGW32 || T.getOS() == Triple::Cygwin ||
 650               T.getOS() == Triple::Win32)) {
 651     Env = IsCOFF;
 652     InitCOFFMCObjectFileInfo(T);
 653   } else {
 654     Env = IsELF;
 655     InitELFMCObjectFileInfo(T);
 656   }
 657 }
 658
 659 void MCObjectFileInfo::InitEHFrameSection() {
 660   if (Env == IsMachO)
 661     EHFrameSection =
 662       Ctx->getMachOSection("__TEXT", "__eh_frame",
 663                            MCSectionMachO::S_COALESCED |
 664                            MCSectionMachO::S_ATTR_NO_TOC |
 665                            MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
 666                            MCSectionMachO::S_ATTR_LIVE_SUPPORT,
 667                            SectionKind::getReadOnly());
 668   else if (Env == IsELF)
 669     EHFrameSection =
 670       Ctx->getELFSection(".eh_frame", EHSectionType,
 671                          EHSectionFlags,
 672                          SectionKind::getDataRel());
 673   else
 674     EHFrameSection =
 675       Ctx->getCOFFSection(".eh_frame",
 676                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 677                           COFF::IMAGE_SCN_MEM_READ |
 678                           COFF::IMAGE_SCN_MEM_WRITE,
 679                           SectionKind::getDataRel());
 680 }