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       T.getArch() != Triple::ppc64le)
  84     SixteenByteConstantSection =   // .literal16
  85       Ctx->getMachOSection("__TEXT", "__literal16",
  86                            MCSectionMachO::S_16BYTE_LITERALS,
  87                            SectionKind::getMergeableConst16());
  88
  89   ReadOnlySection  // .const
  90     = Ctx->getMachOSection("__TEXT", "__const", 0,
  91                            SectionKind::getReadOnly());
  92
  93   TextCoalSection
  94     = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
  95                            MCSectionMachO::S_COALESCED |
  96                            MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
  97                            SectionKind::getText());
  98   ConstTextCoalSection
  99     = Ctx->getMachOSection("__TEXT", "__const_coal",
 100                            MCSectionMachO::S_COALESCED,
 101                            SectionKind::getReadOnly());
 102   ConstDataSection  // .const_data
 103     = Ctx->getMachOSection("__DATA", "__const", 0,
 104                            SectionKind::getReadOnlyWithRel());
 105   DataCoalSection
 106     = Ctx->getMachOSection("__DATA","__datacoal_nt",
 107                            MCSectionMachO::S_COALESCED,
 108                            SectionKind::getDataRel());
 109   DataCommonSection
 110     = Ctx->getMachOSection("__DATA","__common",
 111                            MCSectionMachO::S_ZEROFILL,
 112                            SectionKind::getBSS());
 113   DataBSSSection
 114     = Ctx->getMachOSection("__DATA","__bss", MCSectionMachO::S_ZEROFILL,
 115                            SectionKind::getBSS());
 116
 117
 118   LazySymbolPointerSection
 119     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
 120                            MCSectionMachO::S_LAZY_SYMBOL_POINTERS,
 121                            SectionKind::getMetadata());
 122   NonLazySymbolPointerSection
 123     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
 124                            MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
 125                            SectionKind::getMetadata());
 126
 127   if (RelocM == Reloc::Static) {
 128     StaticCtorSection
 129       = Ctx->getMachOSection("__TEXT", "__constructor", 0,
 130                              SectionKind::getDataRel());
 131     StaticDtorSection
 132       = Ctx->getMachOSection("__TEXT", "__destructor", 0,
 133                              SectionKind::getDataRel());
 134   } else {
 135     StaticCtorSection
 136       = Ctx->getMachOSection("__DATA", "__mod_init_func",
 137                              MCSectionMachO::S_MOD_INIT_FUNC_POINTERS,
 138                              SectionKind::getDataRel());
 139     StaticDtorSection
 140       = Ctx->getMachOSection("__DATA", "__mod_term_func",
 141                              MCSectionMachO::S_MOD_TERM_FUNC_POINTERS,
 142                              SectionKind::getDataRel());
 143   }
 144
 145   // Exception Handling.
 146   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
 147                                      SectionKind::getReadOnlyWithRel());
 148
 149   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) {
 150     CompactUnwindSection =
 151       Ctx->getMachOSection("__LD", "__compact_unwind",
 152                            MCSectionMachO::S_ATTR_DEBUG,
 153                            SectionKind::getReadOnly());
 154
 155     if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)
 156       CompactUnwindDwarfEHFrameOnly = 0x04000000;
 157   }
 158
 159   // Debug Information.
 160   DwarfAccelNamesSection =
 161     Ctx->getMachOSection("__DWARF", "__apple_names",
 162                          MCSectionMachO::S_ATTR_DEBUG,
 163                          SectionKind::getMetadata());
 164   DwarfAccelObjCSection =
 165     Ctx->getMachOSection("__DWARF", "__apple_objc",
 166                          MCSectionMachO::S_ATTR_DEBUG,
 167                          SectionKind::getMetadata());
 168   // 16 character section limit...
 169   DwarfAccelNamespaceSection =
 170     Ctx->getMachOSection("__DWARF", "__apple_namespac",
 171                          MCSectionMachO::S_ATTR_DEBUG,
 172                          SectionKind::getMetadata());
 173   DwarfAccelTypesSection =
 174     Ctx->getMachOSection("__DWARF", "__apple_types",
 175                          MCSectionMachO::S_ATTR_DEBUG,
 176                          SectionKind::getMetadata());
 177
 178   DwarfAbbrevSection =
 179     Ctx->getMachOSection("__DWARF", "__debug_abbrev",
 180                          MCSectionMachO::S_ATTR_DEBUG,
 181                          SectionKind::getMetadata());
 182   DwarfInfoSection =
 183     Ctx->getMachOSection("__DWARF", "__debug_info",
 184                          MCSectionMachO::S_ATTR_DEBUG,
 185                          SectionKind::getMetadata());
 186   DwarfLineSection =
 187     Ctx->getMachOSection("__DWARF", "__debug_line",
 188                          MCSectionMachO::S_ATTR_DEBUG,
 189                          SectionKind::getMetadata());
 190   DwarfFrameSection =
 191     Ctx->getMachOSection("__DWARF", "__debug_frame",
 192                          MCSectionMachO::S_ATTR_DEBUG,
 193                          SectionKind::getMetadata());
 194   DwarfPubNamesSection =
 195     Ctx->getMachOSection("__DWARF", "__debug_pubnames",
 196                          MCSectionMachO::S_ATTR_DEBUG,
 197                          SectionKind::getMetadata());
 198   DwarfPubTypesSection =
 199     Ctx->getMachOSection("__DWARF", "__debug_pubtypes",
 200                          MCSectionMachO::S_ATTR_DEBUG,
 201                          SectionKind::getMetadata());
 202   DwarfStrSection =
 203     Ctx->getMachOSection("__DWARF", "__debug_str",
 204                          MCSectionMachO::S_ATTR_DEBUG,
 205                          SectionKind::getMetadata());
 206   DwarfLocSection =
 207     Ctx->getMachOSection("__DWARF", "__debug_loc",
 208                          MCSectionMachO::S_ATTR_DEBUG,
 209                          SectionKind::getMetadata());
 210   DwarfARangesSection =
 211     Ctx->getMachOSection("__DWARF", "__debug_aranges",
 212                          MCSectionMachO::S_ATTR_DEBUG,
 213                          SectionKind::getMetadata());
 214   DwarfRangesSection =
 215     Ctx->getMachOSection("__DWARF", "__debug_ranges",
 216                          MCSectionMachO::S_ATTR_DEBUG,
 217                          SectionKind::getMetadata());
 218   DwarfMacroInfoSection =
 219     Ctx->getMachOSection("__DWARF", "__debug_macinfo",
 220                          MCSectionMachO::S_ATTR_DEBUG,
 221                          SectionKind::getMetadata());
 222   DwarfDebugInlineSection =
 223     Ctx->getMachOSection("__DWARF", "__debug_inlined",
 224                          MCSectionMachO::S_ATTR_DEBUG,
 225                          SectionKind::getMetadata());
 226
 227   TLSExtraDataSection = TLSTLVSection;
 228 }
 229
 230 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) {
 231   if (T.getArch() == Triple::mips ||
 232       T.getArch() == Triple::mipsel)
 233     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
 234   else if (T.getArch() == Triple::mips64 ||
 235            T.getArch() == Triple::mips64el)
 236     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
 237   else
 238     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 239
 240   if (T.getArch() == Triple::x86) {
 241     PersonalityEncoding = (RelocM == Reloc::PIC_)
 242      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 243      : dwarf::DW_EH_PE_absptr;
 244     LSDAEncoding = (RelocM == Reloc::PIC_)
 245       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 246       : dwarf::DW_EH_PE_absptr;
 247     FDEEncoding = (RelocM == Reloc::PIC_)
 248       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 249       : dwarf::DW_EH_PE_absptr;
 250     TTypeEncoding = (RelocM == Reloc::PIC_)
 251      ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
 252      : dwarf::DW_EH_PE_absptr;
 253   } else if (T.getArch() == Triple::x86_64) {
 254     if (RelocM == Reloc::PIC_) {
 255       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 256         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 257          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 258       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
 259         (CMModel == CodeModel::Small
 260          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 261       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 262       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 263         ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 264          ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
 265     } else {
 266       PersonalityEncoding =
 267         (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
 268         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 269       LSDAEncoding = (CMModel == CodeModel::Small)
 270         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 271       FDEEncoding = dwarf::DW_EH_PE_udata4;
 272       TTypeEncoding = (CMModel == CodeModel::Small)
 273         ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
 274     }
 275   }  else if (T.getArch() ==  Triple::aarch64) {
 276     // The small model guarantees static code/data size < 4GB, but not where it
 277     // will be in memory. Most of these could end up >2GB away so even a signed
 278     // pc-relative 32-bit address is insufficient, theoretically.
 279     if (RelocM == Reloc::PIC_) {
 280       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 281         dwarf::DW_EH_PE_sdata8;
 282       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
 283       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 284       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 285         dwarf::DW_EH_PE_sdata8;
 286     } else {
 287       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 288       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 289       FDEEncoding = dwarf::DW_EH_PE_udata4;
 290       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 291     }
 292   } else if (T.getArch() == Triple::ppc64 || T.getArch() == Triple::ppc64le) {
 293     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 294       dwarf::DW_EH_PE_udata8;
 295     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 296     FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
 297     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 298       dwarf::DW_EH_PE_udata8;
 299   } else if (T.getArch() == Triple::systemz) {
 300     // All currently-defined code models guarantee that 4-byte PC-relative
 301     // values will be in range.
 302     if (RelocM == Reloc::PIC_) {
 303       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 304         dwarf::DW_EH_PE_sdata4;
 305       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 306       FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 307       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
 308         dwarf::DW_EH_PE_sdata4;
 309     } else {
 310       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
 311       LSDAEncoding = dwarf::DW_EH_PE_absptr;
 312       FDEEncoding = dwarf::DW_EH_PE_absptr;
 313       TTypeEncoding = dwarf::DW_EH_PE_absptr;
 314     }
 315   }
 316
 317   // Solaris requires different flags for .eh_frame to seemingly every other
 318   // platform.
 319   EHSectionType = ELF::SHT_PROGBITS;
 320   EHSectionFlags = ELF::SHF_ALLOC;
 321   if (T.getOS() == Triple::Solaris) {
 322     if (T.getArch() == Triple::x86_64)
 323       EHSectionType = ELF::SHT_X86_64_UNWIND;
 324     else
 325       EHSectionFlags |= ELF::SHF_WRITE;
 326   }
 327
 328
 329   // ELF
 330   BSSSection =
 331     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 332                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 333                        SectionKind::getBSS());
 334
 335   TextSection =
 336     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 337                        ELF::SHF_EXECINSTR |
 338                        ELF::SHF_ALLOC,
 339                        SectionKind::getText());
 340
 341   DataSection =
 342     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 343                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 344                        SectionKind::getDataRel());
 345
 346   ReadOnlySection =
 347     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 348                        ELF::SHF_ALLOC,
 349                        SectionKind::getReadOnly());
 350
 351   TLSDataSection =
 352     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 353                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 354                        ELF::SHF_WRITE,
 355                        SectionKind::getThreadData());
 356
 357   TLSBSSSection =
 358     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 359                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 360                        ELF::SHF_WRITE,
 361                        SectionKind::getThreadBSS());
 362
 363   DataRelSection =
 364     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 365                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 366                        SectionKind::getDataRel());
 367
 368   DataRelLocalSection =
 369     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 370                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 371                        SectionKind::getDataRelLocal());
 372
 373   DataRelROSection =
 374     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 375                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 376                        SectionKind::getReadOnlyWithRel());
 377
 378   DataRelROLocalSection =
 379     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 380                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 381                        SectionKind::getReadOnlyWithRelLocal());
 382
 383   MergeableConst4Section =
 384     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 385                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 386                        SectionKind::getMergeableConst4());
 387
 388   MergeableConst8Section =
 389     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 390                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 391                        SectionKind::getMergeableConst8());
 392
 393   MergeableConst16Section =
 394     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 395                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 396                        SectionKind::getMergeableConst16());
 397
 398   StaticCtorSection =
 399     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 400                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 401                        SectionKind::getDataRel());
 402
 403   StaticDtorSection =
 404     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 405                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 406                        SectionKind::getDataRel());
 407
 408   // Exception Handling Sections.
 409
 410   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 411   // it contains relocatable pointers.  In PIC mode, this is probably a big
 412   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 413   // adjusted or this should be a data section.
 414   LSDASection =
 415     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 416                        ELF::SHF_ALLOC,
 417                        SectionKind::getReadOnly());
 418
 419   // Debug Info Sections.
 420   DwarfAbbrevSection =
 421     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 422                        SectionKind::getMetadata());
 423   DwarfInfoSection =
 424     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 425                        SectionKind::getMetadata());
 426   DwarfLineSection =
 427     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 428                        SectionKind::getMetadata());
 429   DwarfFrameSection =
 430     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 431                        SectionKind::getMetadata());
 432   DwarfPubNamesSection =
 433     Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0,
 434                        SectionKind::getMetadata());
 435   DwarfPubTypesSection =
 436     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 437                        SectionKind::getMetadata());
 438   DwarfStrSection =
 439     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 440                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 441                        SectionKind::getMergeable1ByteCString());
 442   DwarfLocSection =
 443     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 444                        SectionKind::getMetadata());
 445   DwarfARangesSection =
 446     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 447                        SectionKind::getMetadata());
 448   DwarfRangesSection =
 449     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 450                        SectionKind::getMetadata());
 451   DwarfMacroInfoSection =
 452     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 453                        SectionKind::getMetadata());
 454
 455   // DWARF5 Experimental Debug Info
 456
 457   // Accelerator Tables
 458   DwarfAccelNamesSection =
 459     Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0,
 460                        SectionKind::getMetadata());
 461   DwarfAccelObjCSection =
 462     Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0,
 463                        SectionKind::getMetadata());
 464   DwarfAccelNamespaceSection =
 465     Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0,
 466                        SectionKind::getMetadata());
 467   DwarfAccelTypesSection =
 468     Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0,
 469                        SectionKind::getMetadata());
 470
 471   // Fission Sections
 472   DwarfInfoDWOSection =
 473     Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0,
 474                        SectionKind::getMetadata());
 475   DwarfAbbrevDWOSection =
 476     Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0,
 477                        SectionKind::getMetadata());
 478   DwarfStrDWOSection =
 479     Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 480                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 481                        SectionKind::getMergeable1ByteCString());
 482   DwarfLineDWOSection =
 483     Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0,
 484                        SectionKind::getMetadata());
 485   DwarfLocDWOSection =
 486     Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0,
 487                        SectionKind::getMetadata());
 488   DwarfStrOffDWOSection =
 489     Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0,
 490                        SectionKind::getMetadata());
 491   DwarfAddrSection =
 492     Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0,
 493                        SectionKind::getMetadata());
 494 }
 495
 496
 497 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 498   // COFF
 499   TextSection =
 500     Ctx->getCOFFSection(".text",
 501                         COFF::IMAGE_SCN_CNT_CODE |
 502                         COFF::IMAGE_SCN_MEM_EXECUTE |
 503                         COFF::IMAGE_SCN_MEM_READ,
 504                         SectionKind::getText());
 505   DataSection =
 506     Ctx->getCOFFSection(".data",
 507                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 508                         COFF::IMAGE_SCN_MEM_READ |
 509                         COFF::IMAGE_SCN_MEM_WRITE,
 510                         SectionKind::getDataRel());
 511   ReadOnlySection =
 512     Ctx->getCOFFSection(".rdata",
 513                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 514                         COFF::IMAGE_SCN_MEM_READ,
 515                         SectionKind::getReadOnly());
 516   if (T.getOS() == Triple::Win32) {
 517     StaticCtorSection =
 518       Ctx->getCOFFSection(".CRT$XCU",
 519                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 520                           COFF::IMAGE_SCN_MEM_READ,
 521                           SectionKind::getReadOnly());
 522   } else {
 523     StaticCtorSection =
 524       Ctx->getCOFFSection(".ctors",
 525                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 526                           COFF::IMAGE_SCN_MEM_READ |
 527                           COFF::IMAGE_SCN_MEM_WRITE,
 528                           SectionKind::getDataRel());
 529   }
 530
 531
 532   if (T.getOS() == Triple::Win32) {
 533     StaticDtorSection =
 534       Ctx->getCOFFSection(".CRT$XTX",
 535                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 536                           COFF::IMAGE_SCN_MEM_READ,
 537                           SectionKind::getReadOnly());
 538   } else {
 539     StaticDtorSection =
 540       Ctx->getCOFFSection(".dtors",
 541                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 542                           COFF::IMAGE_SCN_MEM_READ |
 543                           COFF::IMAGE_SCN_MEM_WRITE,
 544                           SectionKind::getDataRel());
 545   }
 546
 547   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 548   // though it contains relocatable pointers.  In PIC mode, this is probably a
 549   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 550   // adjusted or this should be a data section.
 551   LSDASection =
 552     Ctx->getCOFFSection(".gcc_except_table",
 553                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 554                         COFF::IMAGE_SCN_MEM_READ,
 555                         SectionKind::getReadOnly());
 556
 557   // Debug info.
 558   DwarfAbbrevSection =
 559     Ctx->getCOFFSection(".debug_abbrev",
 560                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 561                         COFF::IMAGE_SCN_MEM_READ,
 562                         SectionKind::getMetadata());
 563   DwarfInfoSection =
 564     Ctx->getCOFFSection(".debug_info",
 565                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 566                         COFF::IMAGE_SCN_MEM_READ,
 567                         SectionKind::getMetadata());
 568   DwarfLineSection =
 569     Ctx->getCOFFSection(".debug_line",
 570                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 571                         COFF::IMAGE_SCN_MEM_READ,
 572                         SectionKind::getMetadata());
 573   DwarfFrameSection =
 574     Ctx->getCOFFSection(".debug_frame",
 575                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 576                         COFF::IMAGE_SCN_MEM_READ,
 577                         SectionKind::getMetadata());
 578   DwarfPubNamesSection =
 579     Ctx->getCOFFSection(".debug_pubnames",
 580                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 581                         COFF::IMAGE_SCN_MEM_READ,
 582                         SectionKind::getMetadata());
 583   DwarfPubTypesSection =
 584     Ctx->getCOFFSection(".debug_pubtypes",
 585                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 586                         COFF::IMAGE_SCN_MEM_READ,
 587                         SectionKind::getMetadata());
 588   DwarfStrSection =
 589     Ctx->getCOFFSection(".debug_str",
 590                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 591                         COFF::IMAGE_SCN_MEM_READ,
 592                         SectionKind::getMetadata());
 593   DwarfLocSection =
 594     Ctx->getCOFFSection(".debug_loc",
 595                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 596                         COFF::IMAGE_SCN_MEM_READ,
 597                         SectionKind::getMetadata());
 598   DwarfARangesSection =
 599     Ctx->getCOFFSection(".debug_aranges",
 600                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 601                         COFF::IMAGE_SCN_MEM_READ,
 602                         SectionKind::getMetadata());
 603   DwarfRangesSection =
 604     Ctx->getCOFFSection(".debug_ranges",
 605                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 606                         COFF::IMAGE_SCN_MEM_READ,
 607                         SectionKind::getMetadata());
 608   DwarfMacroInfoSection =
 609     Ctx->getCOFFSection(".debug_macinfo",
 610                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 611                         COFF::IMAGE_SCN_MEM_READ,
 612                         SectionKind::getMetadata());
 613
 614   DrectveSection =
 615     Ctx->getCOFFSection(".drectve",
 616                         COFF::IMAGE_SCN_LNK_INFO,
 617                         SectionKind::getMetadata());
 618
 619   PDataSection =
 620     Ctx->getCOFFSection(".pdata",
 621                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 622                         COFF::IMAGE_SCN_MEM_READ,
 623                         SectionKind::getDataRel());
 624
 625   XDataSection =
 626     Ctx->getCOFFSection(".xdata",
 627                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 628                         COFF::IMAGE_SCN_MEM_READ,
 629                         SectionKind::getDataRel());
 630   TLSDataSection =
 631     Ctx->getCOFFSection(".tls$",
 632                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 633                         COFF::IMAGE_SCN_MEM_READ |
 634                         COFF::IMAGE_SCN_MEM_WRITE,
 635                         SectionKind::getDataRel());
 636 }
 637
 638 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
 639                                             CodeModel::Model cm,
 640                                             MCContext &ctx) {
 641   RelocM = relocm;
 642   CMModel = cm;
 643   Ctx = &ctx;
 644
 645   // Common.
 646   CommDirectiveSupportsAlignment = true;
 647   SupportsWeakOmittedEHFrame = true;
 648   IsFunctionEHFrameSymbolPrivate = true;
 649
 650   PersonalityEncoding = LSDAEncoding = FDEEncoding = FDECFIEncoding =
 651     TTypeEncoding = dwarf::DW_EH_PE_absptr;
 652
 653   CompactUnwindDwarfEHFrameOnly = 0;
 654
 655   EHFrameSection = 0;             // Created on demand.
 656   CompactUnwindSection = 0;       // Used only by selected targets.
 657   DwarfAccelNamesSection = 0;     // Used only by selected targets.
 658   DwarfAccelObjCSection = 0;      // Used only by selected targets.
 659   DwarfAccelNamespaceSection = 0; // Used only by selected targets.
 660   DwarfAccelTypesSection = 0;     // Used only by selected targets.
 661
 662   Triple T(TT);
 663   Triple::ArchType Arch = T.getArch();
 664   // FIXME: Checking for Arch here to filter out bogus triples such as
 665   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 666   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 667        Arch == Triple::arm || Arch == Triple::thumb ||
 668        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 669        Arch == Triple::UnknownArch) &&
 670       (T.isOSDarwin() || T.getEnvironment() == Triple::MachO)) {
 671     Env = IsMachO;
 672     InitMachOMCObjectFileInfo(T);
 673   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64) &&
 674              (T.getEnvironment() != Triple::ELF) &&
 675              (T.getOS() == Triple::MinGW32 || T.getOS() == Triple::Cygwin ||
 676               T.getOS() == Triple::Win32)) {
 677     Env = IsCOFF;
 678     InitCOFFMCObjectFileInfo(T);
 679   } else {
 680     Env = IsELF;
 681     InitELFMCObjectFileInfo(T);
 682   }
 683 }
 684
 685 void MCObjectFileInfo::InitEHFrameSection() {
 686   if (Env == IsMachO)
 687     EHFrameSection =
 688       Ctx->getMachOSection("__TEXT", "__eh_frame",
 689                            MCSectionMachO::S_COALESCED |
 690                            MCSectionMachO::S_ATTR_NO_TOC |
 691                            MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
 692                            MCSectionMachO::S_ATTR_LIVE_SUPPORT,
 693                            SectionKind::getReadOnly());
 694   else if (Env == IsELF)
 695     EHFrameSection =
 696       Ctx->getELFSection(".eh_frame", EHSectionType,
 697                          EHSectionFlags,
 698                          SectionKind::getDataRel());
 699   else
 700     EHFrameSection =
 701       Ctx->getCOFFSection(".eh_frame",
 702                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 703                           COFF::IMAGE_SCN_MEM_READ |
 704                           COFF::IMAGE_SCN_MEM_WRITE,
 705                           SectionKind::getDataRel());
 706 }