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   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   // Solaris requires different flags for .eh_frame to seemingly every other
 262   // platform.
 263   EHSectionType = ELF::SHT_PROGBITS;
 264   EHSectionFlags = ELF::SHF_ALLOC;
 265   if (T.getOS() == Triple::Solaris) {
 266     if (T.getArch() == Triple::x86_64)
 267       EHSectionType = ELF::SHT_X86_64_UNWIND;
 268     else
 269       EHSectionFlags |= ELF::SHF_WRITE;
 270   }
 271
 272
 273   // ELF
 274   BSSSection =
 275     Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 276                        ELF::SHF_WRITE | ELF::SHF_ALLOC,
 277                        SectionKind::getBSS());
 278
 279   TextSection =
 280     Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 281                        ELF::SHF_EXECINSTR |
 282                        ELF::SHF_ALLOC,
 283                        SectionKind::getText());
 284
 285   DataSection =
 286     Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 287                        ELF::SHF_WRITE |ELF::SHF_ALLOC,
 288                        SectionKind::getDataRel());
 289
 290   ReadOnlySection =
 291     Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS,
 292                        ELF::SHF_ALLOC,
 293                        SectionKind::getReadOnly());
 294
 295   TLSDataSection =
 296     Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 297                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 298                        ELF::SHF_WRITE,
 299                        SectionKind::getThreadData());
 300
 301   TLSBSSSection =
 302     Ctx->getELFSection(".tbss", ELF::SHT_NOBITS,
 303                        ELF::SHF_ALLOC | ELF::SHF_TLS |
 304                        ELF::SHF_WRITE,
 305                        SectionKind::getThreadBSS());
 306
 307   DataRelSection =
 308     Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
 309                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 310                        SectionKind::getDataRel());
 311
 312   DataRelLocalSection =
 313     Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
 314                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 315                        SectionKind::getDataRelLocal());
 316
 317   DataRelROSection =
 318     Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 319                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 320                        SectionKind::getReadOnlyWithRel());
 321
 322   DataRelROLocalSection =
 323     Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS,
 324                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 325                        SectionKind::getReadOnlyWithRelLocal());
 326
 327   MergeableConst4Section =
 328     Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 329                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 330                        SectionKind::getMergeableConst4());
 331
 332   MergeableConst8Section =
 333     Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 334                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 335                        SectionKind::getMergeableConst8());
 336
 337   MergeableConst16Section =
 338     Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 339                        ELF::SHF_ALLOC |ELF::SHF_MERGE,
 340                        SectionKind::getMergeableConst16());
 341
 342   StaticCtorSection =
 343     Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
 344                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 345                        SectionKind::getDataRel());
 346
 347   StaticDtorSection =
 348     Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
 349                        ELF::SHF_ALLOC |ELF::SHF_WRITE,
 350                        SectionKind::getDataRel());
 351
 352   // Exception Handling Sections.
 353
 354   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 355   // it contains relocatable pointers.  In PIC mode, this is probably a big
 356   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 357   // adjusted or this should be a data section.
 358   LSDASection =
 359     Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 360                        ELF::SHF_ALLOC,
 361                        SectionKind::getReadOnly());
 362
 363   // Debug Info Sections.
 364   DwarfAbbrevSection =
 365     Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
 366                        SectionKind::getMetadata());
 367   DwarfInfoSection =
 368     Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0,
 369                        SectionKind::getMetadata());
 370   DwarfLineSection =
 371     Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0,
 372                        SectionKind::getMetadata());
 373   DwarfFrameSection =
 374     Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0,
 375                        SectionKind::getMetadata());
 376   DwarfPubTypesSection =
 377     Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0,
 378                        SectionKind::getMetadata());
 379   DwarfStrSection =
 380     Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
 381                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 382                        SectionKind::getMergeable1ByteCString());
 383   DwarfLocSection =
 384     Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0,
 385                        SectionKind::getMetadata());
 386   DwarfARangesSection =
 387     Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0,
 388                        SectionKind::getMetadata());
 389   DwarfRangesSection =
 390     Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0,
 391                        SectionKind::getMetadata());
 392   DwarfMacroInfoSection =
 393     Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0,
 394                        SectionKind::getMetadata());
 395
 396   // DWARF5 Experimental Debug Info
 397
 398   // Accelerator Tables
 399   DwarfAccelNamesSection =
 400     Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0,
 401                        SectionKind::getMetadata());
 402   DwarfAccelObjCSection =
 403     Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0,
 404                        SectionKind::getMetadata());
 405   DwarfAccelNamespaceSection =
 406     Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0,
 407                        SectionKind::getMetadata());
 408   DwarfAccelTypesSection =
 409     Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0,
 410                        SectionKind::getMetadata());
 411
 412   // Fission Sections
 413   DwarfInfoDWOSection =
 414     Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0,
 415                        SectionKind::getMetadata());
 416   DwarfAbbrevDWOSection =
 417     Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0,
 418                        SectionKind::getMetadata());
 419   DwarfStrDWOSection =
 420     Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
 421                        ELF::SHF_MERGE | ELF::SHF_STRINGS,
 422                        SectionKind::getMergeable1ByteCString());
 423   DwarfLineDWOSection =
 424     Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0,
 425                        SectionKind::getMetadata());
 426   DwarfLocDWOSection =
 427     Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0,
 428                        SectionKind::getMetadata());
 429   DwarfStrOffDWOSection =
 430     Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0,
 431                        SectionKind::getMetadata());
 432 }
 433
 434
 435 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) {
 436   // COFF
 437   TextSection =
 438     Ctx->getCOFFSection(".text",
 439                         COFF::IMAGE_SCN_CNT_CODE |
 440                         COFF::IMAGE_SCN_MEM_EXECUTE |
 441                         COFF::IMAGE_SCN_MEM_READ,
 442                         SectionKind::getText());
 443   DataSection =
 444     Ctx->getCOFFSection(".data",
 445                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 446                         COFF::IMAGE_SCN_MEM_READ |
 447                         COFF::IMAGE_SCN_MEM_WRITE,
 448                         SectionKind::getDataRel());
 449   ReadOnlySection =
 450     Ctx->getCOFFSection(".rdata",
 451                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 452                         COFF::IMAGE_SCN_MEM_READ,
 453                         SectionKind::getReadOnly());
 454   if (T.getOS() == Triple::Win32) {
 455     StaticCtorSection =
 456       Ctx->getCOFFSection(".CRT$XCU",
 457                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 458                           COFF::IMAGE_SCN_MEM_READ,
 459                           SectionKind::getReadOnly());
 460   } else {
 461     StaticCtorSection =
 462       Ctx->getCOFFSection(".ctors",
 463                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 464                           COFF::IMAGE_SCN_MEM_READ |
 465                           COFF::IMAGE_SCN_MEM_WRITE,
 466                           SectionKind::getDataRel());
 467   }
 468
 469
 470   if (T.getOS() == Triple::Win32) {
 471     StaticDtorSection =
 472       Ctx->getCOFFSection(".CRT$XTX",
 473                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 474                           COFF::IMAGE_SCN_MEM_READ,
 475                           SectionKind::getReadOnly());
 476   } else {
 477     StaticDtorSection =
 478       Ctx->getCOFFSection(".dtors",
 479                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 480                           COFF::IMAGE_SCN_MEM_READ |
 481                           COFF::IMAGE_SCN_MEM_WRITE,
 482                           SectionKind::getDataRel());
 483   }
 484
 485   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
 486   // though it contains relocatable pointers.  In PIC mode, this is probably a
 487   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
 488   // adjusted or this should be a data section.
 489   LSDASection =
 490     Ctx->getCOFFSection(".gcc_except_table",
 491                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 492                         COFF::IMAGE_SCN_MEM_READ,
 493                         SectionKind::getReadOnly());
 494
 495   // Debug info.
 496   DwarfAbbrevSection =
 497     Ctx->getCOFFSection(".debug_abbrev",
 498                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 499                         COFF::IMAGE_SCN_MEM_READ,
 500                         SectionKind::getMetadata());
 501   DwarfInfoSection =
 502     Ctx->getCOFFSection(".debug_info",
 503                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 504                         COFF::IMAGE_SCN_MEM_READ,
 505                         SectionKind::getMetadata());
 506   DwarfLineSection =
 507     Ctx->getCOFFSection(".debug_line",
 508                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 509                         COFF::IMAGE_SCN_MEM_READ,
 510                         SectionKind::getMetadata());
 511   DwarfFrameSection =
 512     Ctx->getCOFFSection(".debug_frame",
 513                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 514                         COFF::IMAGE_SCN_MEM_READ,
 515                         SectionKind::getMetadata());
 516   DwarfPubTypesSection =
 517     Ctx->getCOFFSection(".debug_pubtypes",
 518                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 519                         COFF::IMAGE_SCN_MEM_READ,
 520                         SectionKind::getMetadata());
 521   DwarfStrSection =
 522     Ctx->getCOFFSection(".debug_str",
 523                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 524                         COFF::IMAGE_SCN_MEM_READ,
 525                         SectionKind::getMetadata());
 526   DwarfLocSection =
 527     Ctx->getCOFFSection(".debug_loc",
 528                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 529                         COFF::IMAGE_SCN_MEM_READ,
 530                         SectionKind::getMetadata());
 531   DwarfARangesSection =
 532     Ctx->getCOFFSection(".debug_aranges",
 533                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 534                         COFF::IMAGE_SCN_MEM_READ,
 535                         SectionKind::getMetadata());
 536   DwarfRangesSection =
 537     Ctx->getCOFFSection(".debug_ranges",
 538                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 539                         COFF::IMAGE_SCN_MEM_READ,
 540                         SectionKind::getMetadata());
 541   DwarfMacroInfoSection =
 542     Ctx->getCOFFSection(".debug_macinfo",
 543                         COFF::IMAGE_SCN_MEM_DISCARDABLE |
 544                         COFF::IMAGE_SCN_MEM_READ,
 545                         SectionKind::getMetadata());
 546
 547   DrectveSection =
 548     Ctx->getCOFFSection(".drectve",
 549                         COFF::IMAGE_SCN_LNK_INFO,
 550                         SectionKind::getMetadata());
 551
 552   PDataSection =
 553     Ctx->getCOFFSection(".pdata",
 554                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 555                         COFF::IMAGE_SCN_MEM_READ,
 556                         SectionKind::getDataRel());
 557
 558   XDataSection =
 559     Ctx->getCOFFSection(".xdata",
 560                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 561                         COFF::IMAGE_SCN_MEM_READ,
 562                         SectionKind::getDataRel());
 563   TLSDataSection =
 564     Ctx->getCOFFSection(".tls$",
 565                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 566                         COFF::IMAGE_SCN_MEM_READ |
 567                         COFF::IMAGE_SCN_MEM_WRITE,
 568                         SectionKind::getDataRel());
 569 }
 570
 571 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
 572                                             CodeModel::Model cm,
 573                                             MCContext &ctx) {
 574   RelocM = relocm;
 575   CMModel = cm;
 576   Ctx = &ctx;
 577
 578   // Common.
 579   CommDirectiveSupportsAlignment = true;
 580   SupportsWeakOmittedEHFrame = true;
 581   IsFunctionEHFrameSymbolPrivate = true;
 582
 583   PersonalityEncoding = LSDAEncoding = FDEEncoding = FDECFIEncoding =
 584     TTypeEncoding = dwarf::DW_EH_PE_absptr;
 585
 586   EHFrameSection = 0;             // Created on demand.
 587   CompactUnwindSection = 0;       // Used only by selected targets.
 588   DwarfAccelNamesSection = 0;     // Used only by selected targets.
 589   DwarfAccelObjCSection = 0;      // Used only by selected targets.
 590   DwarfAccelNamespaceSection = 0; // Used only by selected targets.
 591   DwarfAccelTypesSection = 0;     // Used only by selected targets.
 592
 593   Triple T(TT);
 594   Triple::ArchType Arch = T.getArch();
 595   // FIXME: Checking for Arch here to filter out bogus triples such as
 596   // cellspu-apple-darwin. Perhaps we should fix in Triple?
 597   if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
 598        Arch == Triple::arm || Arch == Triple::thumb ||
 599        Arch == Triple::ppc || Arch == Triple::ppc64 ||
 600        Arch == Triple::UnknownArch) &&
 601       (T.isOSDarwin() || T.getEnvironment() == Triple::MachO)) {
 602     Env = IsMachO;
 603     InitMachOMCObjectFileInfo(T);
 604   } else if ((Arch == Triple::x86 || Arch == Triple::x86_64) &&
 605              (T.getEnvironment() != Triple::ELF) &&
 606              (T.getOS() == Triple::MinGW32 || T.getOS() == Triple::Cygwin ||
 607               T.getOS() == Triple::Win32)) {
 608     Env = IsCOFF;
 609     InitCOFFMCObjectFileInfo(T);
 610   } else {
 611     Env = IsELF;
 612     InitELFMCObjectFileInfo(T);
 613   }
 614 }
 615
 616 void MCObjectFileInfo::InitEHFrameSection() {
 617   if (Env == IsMachO)
 618     EHFrameSection =
 619       Ctx->getMachOSection("__TEXT", "__eh_frame",
 620                            MCSectionMachO::S_COALESCED |
 621                            MCSectionMachO::S_ATTR_NO_TOC |
 622                            MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
 623                            MCSectionMachO::S_ATTR_LIVE_SUPPORT,
 624                            SectionKind::getReadOnly());
 625   else if (Env == IsELF)
 626     EHFrameSection =
 627       Ctx->getELFSection(".eh_frame", EHSectionType,
 628                          EHSectionFlags,
 629                          SectionKind::getDataRel());
 630   else
 631     EHFrameSection =
 632       Ctx->getCOFFSection(".eh_frame",
 633                           COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 634                           COFF::IMAGE_SCN_MEM_READ |
 635                           COFF::IMAGE_SCN_MEM_WRITE,
 636                           SectionKind::getDataRel());
 637 }