llvm/lib/MC/MCObjectFileInfo.cpp

   1 //===-- MCObjectFileInfo.cpp - Object File Information --------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/MC/MCObjectFileInfo.h"
  10 #include "llvm/ADT/StringExtras.h"
  11 #include "llvm/ADT/Triple.h"
  12 #include "llvm/BinaryFormat/COFF.h"
  13 #include "llvm/BinaryFormat/ELF.h"
  14 #include "llvm/BinaryFormat/Wasm.h"
  15 #include "llvm/MC/MCAsmInfo.h"
  16 #include "llvm/MC/MCContext.h"
  17 #include "llvm/MC/MCSection.h"
  18 #include "llvm/MC/MCSectionCOFF.h"
  19 #include "llvm/MC/MCSectionELF.h"
  20 #include "llvm/MC/MCSectionGOFF.h"
  21 #include "llvm/MC/MCSectionMachO.h"
  22 #include "llvm/MC/MCSectionWasm.h"
  23 #include "llvm/MC/MCSectionXCOFF.h"
  24
  25 using namespace llvm;
  26
  27 static bool useCompactUnwind(const Triple &T) {
  28   // Only on darwin.
  29   if (!T.isOSDarwin())
  30     return false;
  31
  32   // aarch64 always has it.
  33   if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
  34     return true;
  35
  36   // armv7k always has it.
  37   if (T.isWatchABI())
  38     return true;
  39
  40   // Use it on newer version of OS X.
  41   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
  42     return true;
  43
  44   // And the iOS simulator.
  45   if (T.isiOS() && T.isX86())
  46     return true;
  47
  48   return false;
  49 }
  50
  51 void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
  52   // MachO
  53   SupportsWeakOmittedEHFrame = false;
  54
  55   EHFrameSection = Ctx->getMachOSection(
  56       "__TEXT", "__eh_frame",
  57       MachO::S_COALESCED | MachO::S_ATTR_NO_TOC |
  58           MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT,
  59       SectionKind::getReadOnly());
  60
  61   if (T.isOSDarwin() &&
  62       (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32))
  63     SupportsCompactUnwindWithoutEHFrame = true;
  64
  65   if (T.isWatchABI())
  66     OmitDwarfIfHaveCompactUnwind = true;
  67
  68   FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
  69
  70   // .comm doesn't support alignment before Leopard.
  71   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
  72     CommDirectiveSupportsAlignment = false;
  73
  74   TextSection // .text
  75     = Ctx->getMachOSection("__TEXT", "__text",
  76                            MachO::S_ATTR_PURE_INSTRUCTIONS,
  77                            SectionKind::getText());
  78   DataSection // .data
  79       = Ctx->getMachOSection("__DATA", "__data", 0, SectionKind::getData());
  80
  81   // BSSSection might not be expected initialized on msvc.
  82   BSSSection = nullptr;
  83
  84   TLSDataSection // .tdata
  85       = Ctx->getMachOSection("__DATA", "__thread_data",
  86                              MachO::S_THREAD_LOCAL_REGULAR,
  87                              SectionKind::getData());
  88   TLSBSSSection // .tbss
  89     = Ctx->getMachOSection("__DATA", "__thread_bss",
  90                            MachO::S_THREAD_LOCAL_ZEROFILL,
  91                            SectionKind::getThreadBSS());
  92
  93   // TODO: Verify datarel below.
  94   TLSTLVSection // .tlv
  95       = Ctx->getMachOSection("__DATA", "__thread_vars",
  96                              MachO::S_THREAD_LOCAL_VARIABLES,
  97                              SectionKind::getData());
  98
  99   TLSThreadInitSection = Ctx->getMachOSection(
 100       "__DATA", "__thread_init", MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
 101       SectionKind::getData());
 102
 103   CStringSection // .cstring
 104     = Ctx->getMachOSection("__TEXT", "__cstring",
 105                            MachO::S_CSTRING_LITERALS,
 106                            SectionKind::getMergeable1ByteCString());
 107   UStringSection
 108     = Ctx->getMachOSection("__TEXT","__ustring", 0,
 109                            SectionKind::getMergeable2ByteCString());
 110   FourByteConstantSection // .literal4
 111     = Ctx->getMachOSection("__TEXT", "__literal4",
 112                            MachO::S_4BYTE_LITERALS,
 113                            SectionKind::getMergeableConst4());
 114   EightByteConstantSection // .literal8
 115     = Ctx->getMachOSection("__TEXT", "__literal8",
 116                            MachO::S_8BYTE_LITERALS,
 117                            SectionKind::getMergeableConst8());
 118
 119   SixteenByteConstantSection // .literal16
 120       = Ctx->getMachOSection("__TEXT", "__literal16",
 121                              MachO::S_16BYTE_LITERALS,
 122                              SectionKind::getMergeableConst16());
 123
 124   ReadOnlySection  // .const
 125     = Ctx->getMachOSection("__TEXT", "__const", 0,
 126                            SectionKind::getReadOnly());
 127
 128   // If the target is not powerpc, map the coal sections to the non-coal
 129   // sections.
 130   //
 131   // "__TEXT/__textcoal_nt" => section "__TEXT/__text"
 132   // "__TEXT/__const_coal"  => section "__TEXT/__const"
 133   // "__DATA/__datacoal_nt" => section "__DATA/__data"
 134   Triple::ArchType ArchTy = T.getArch();
 135
 136   ConstDataSection  // .const_data
 137     = Ctx->getMachOSection("__DATA", "__const", 0,
 138                            SectionKind::getReadOnlyWithRel());
 139
 140   if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) {
 141     TextCoalSection
 142       = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
 143                              MachO::S_COALESCED |
 144                              MachO::S_ATTR_PURE_INSTRUCTIONS,
 145                              SectionKind::getText());
 146     ConstTextCoalSection
 147       = Ctx->getMachOSection("__TEXT", "__const_coal",
 148                              MachO::S_COALESCED,
 149                              SectionKind::getReadOnly());
 150     DataCoalSection = Ctx->getMachOSection(
 151         "__DATA", "__datacoal_nt", MachO::S_COALESCED, SectionKind::getData());
 152     ConstDataCoalSection = DataCoalSection;
 153   } else {
 154     TextCoalSection = TextSection;
 155     ConstTextCoalSection = ReadOnlySection;
 156     DataCoalSection = DataSection;
 157     ConstDataCoalSection = ConstDataSection;
 158   }
 159
 160   DataCommonSection
 161     = Ctx->getMachOSection("__DATA","__common",
 162                            MachO::S_ZEROFILL,
 163                            SectionKind::getBSS());
 164   DataBSSSection
 165     = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
 166                            SectionKind::getBSS());
 167
 168
 169   LazySymbolPointerSection
 170     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
 171                            MachO::S_LAZY_SYMBOL_POINTERS,
 172                            SectionKind::getMetadata());
 173   NonLazySymbolPointerSection
 174     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
 175                            MachO::S_NON_LAZY_SYMBOL_POINTERS,
 176                            SectionKind::getMetadata());
 177
 178   ThreadLocalPointerSection
 179     = Ctx->getMachOSection("__DATA", "__thread_ptr",
 180                            MachO::S_THREAD_LOCAL_VARIABLE_POINTERS,
 181                            SectionKind::getMetadata());
 182
 183   // Exception Handling.
 184   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
 185                                      SectionKind::getReadOnlyWithRel());
 186
 187   COFFDebugSymbolsSection = nullptr;
 188   COFFDebugTypesSection = nullptr;
 189   COFFGlobalTypeHashesSection = nullptr;
 190
 191   if (useCompactUnwind(T)) {
 192     CompactUnwindSection =
 193         Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
 194                              SectionKind::getReadOnly());
 195
 196     if (T.isX86())
 197       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_X86_64_MODE_DWARF
 198     else if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
 199       CompactUnwindDwarfEHFrameOnly = 0x03000000;  // UNWIND_ARM64_MODE_DWARF
 200     else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb)
 201       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_ARM_MODE_DWARF
 202   }
 203
 204   // Debug Information.
 205   DwarfDebugNamesSection =
 206       Ctx->getMachOSection("__DWARF", "__debug_names", MachO::S_ATTR_DEBUG,
 207                            SectionKind::getMetadata(), "debug_names_begin");
 208   DwarfAccelNamesSection =
 209       Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG,
 210                            SectionKind::getMetadata(), "names_begin");
 211   DwarfAccelObjCSection =
 212       Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG,
 213                            SectionKind::getMetadata(), "objc_begin");
 214   // 16 character section limit...
 215   DwarfAccelNamespaceSection =
 216       Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG,
 217                            SectionKind::getMetadata(), "namespac_begin");
 218   DwarfAccelTypesSection =
 219       Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG,
 220                            SectionKind::getMetadata(), "types_begin");
 221
 222   DwarfSwiftASTSection =
 223       Ctx->getMachOSection("__DWARF", "__swift_ast", MachO::S_ATTR_DEBUG,
 224                            SectionKind::getMetadata());
 225
 226   DwarfAbbrevSection =
 227       Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG,
 228                            SectionKind::getMetadata(), "section_abbrev");
 229   DwarfInfoSection =
 230       Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG,
 231                            SectionKind::getMetadata(), "section_info");
 232   DwarfLineSection =
 233       Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG,
 234                            SectionKind::getMetadata(), "section_line");
 235   DwarfLineStrSection =
 236       Ctx->getMachOSection("__DWARF", "__debug_line_str", MachO::S_ATTR_DEBUG,
 237                            SectionKind::getMetadata(), "section_line_str");
 238   DwarfFrameSection =
 239       Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG,
 240                            SectionKind::getMetadata());
 241   DwarfPubNamesSection =
 242       Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG,
 243                            SectionKind::getMetadata());
 244   DwarfPubTypesSection =
 245       Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG,
 246                            SectionKind::getMetadata());
 247   DwarfGnuPubNamesSection =
 248       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG,
 249                            SectionKind::getMetadata());
 250   DwarfGnuPubTypesSection =
 251       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG,
 252                            SectionKind::getMetadata());
 253   DwarfStrSection =
 254       Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG,
 255                            SectionKind::getMetadata(), "info_string");
 256   DwarfStrOffSection =
 257       Ctx->getMachOSection("__DWARF", "__debug_str_offs", MachO::S_ATTR_DEBUG,
 258                            SectionKind::getMetadata(), "section_str_off");
 259   DwarfAddrSection =
 260       Ctx->getMachOSection("__DWARF", "__debug_addr", MachO::S_ATTR_DEBUG,
 261                            SectionKind::getMetadata(), "section_info");
 262   DwarfLocSection =
 263       Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG,
 264                            SectionKind::getMetadata(), "section_debug_loc");
 265   DwarfLoclistsSection =
 266       Ctx->getMachOSection("__DWARF", "__debug_loclists", MachO::S_ATTR_DEBUG,
 267                            SectionKind::getMetadata(), "section_debug_loc");
 268
 269   DwarfARangesSection =
 270       Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG,
 271                            SectionKind::getMetadata());
 272   DwarfRangesSection =
 273       Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG,
 274                            SectionKind::getMetadata(), "debug_range");
 275   DwarfRnglistsSection =
 276       Ctx->getMachOSection("__DWARF", "__debug_rnglists", MachO::S_ATTR_DEBUG,
 277                            SectionKind::getMetadata(), "debug_range");
 278   DwarfMacinfoSection =
 279       Ctx->getMachOSection("__DWARF", "__debug_macinfo", MachO::S_ATTR_DEBUG,
 280                            SectionKind::getMetadata(), "debug_macinfo");
 281   DwarfMacroSection =
 282       Ctx->getMachOSection("__DWARF", "__debug_macro", MachO::S_ATTR_DEBUG,
 283                            SectionKind::getMetadata(), "debug_macro");
 284   DwarfDebugInlineSection =
 285       Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG,
 286                            SectionKind::getMetadata());
 287   DwarfCUIndexSection =
 288       Ctx->getMachOSection("__DWARF", "__debug_cu_index", MachO::S_ATTR_DEBUG,
 289                            SectionKind::getMetadata());
 290   DwarfTUIndexSection =
 291       Ctx->getMachOSection("__DWARF", "__debug_tu_index", MachO::S_ATTR_DEBUG,
 292                            SectionKind::getMetadata());
 293   StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
 294                                          0, SectionKind::getMetadata());
 295
 296   FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
 297                                          0, SectionKind::getMetadata());
 298
 299   RemarksSection = Ctx->getMachOSection(
 300       "__LLVM", "__remarks", MachO::S_ATTR_DEBUG, SectionKind::getMetadata());
 301
 302   TLSExtraDataSection = TLSTLVSection;
 303 }
 304
 305 void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
 306   switch (T.getArch()) {
 307   case Triple::mips:
 308   case Triple::mipsel:
 309   case Triple::mips64:
 310   case Triple::mips64el:
 311     // We cannot use DW_EH_PE_sdata8 for the large PositionIndependent case
 312     // since there is no R_MIPS_PC64 relocation (only a 32-bit version).
 313     if (PositionIndependent && !Large)
 314       FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 315     else
 316       FDECFIEncoding = Ctx->getAsmInfo()->getCodePointerSize() == 4
 317                            ? dwarf::DW_EH_PE_sdata4
 318                            : dwarf::DW_EH_PE_sdata8;
 319     break;
 320   case Triple::ppc64:
 321   case Triple::ppc64le:
 322   case Triple::aarch64:
 323   case Triple::aarch64_be:
 324   case Triple::x86_64:
 325     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
 326                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
 327     break;
 328   case Triple::bpfel:
 329   case Triple::bpfeb:
 330     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
 331     break;
 332   case Triple::hexagon:
 333     FDECFIEncoding =
 334         PositionIndependent ? dwarf::DW_EH_PE_pcrel : dwarf::DW_EH_PE_absptr;
 335     break;
 336   default:
 337     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 338     break;
 339   }
 340
 341   unsigned EHSectionType = T.getArch() == Triple::x86_64
 342                                ? ELF::SHT_X86_64_UNWIND
 343                                : ELF::SHT_PROGBITS;
 344
 345   // Solaris requires different flags for .eh_frame to seemingly every other
 346   // platform.
 347   unsigned EHSectionFlags = ELF::SHF_ALLOC;
 348   if (T.isOSSolaris() && T.getArch() != Triple::x86_64)
 349     EHSectionFlags |= ELF::SHF_WRITE;
 350
 351   // ELF
 352   BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
 353                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);
 354
 355   TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
 356                                    ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);
 357
 358   DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
 359                                    ELF::SHF_WRITE | ELF::SHF_ALLOC);
 360
 361   ReadOnlySection =
 362       Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
 363
 364   TLSDataSection =
 365       Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
 366                          ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
 367
 368   TLSBSSSection = Ctx->getELFSection(
 369       ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
 370
 371   DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
 372                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);
 373
 374   MergeableConst4Section =
 375       Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
 376                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 4);
 377
 378   MergeableConst8Section =
 379       Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
 380                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 8);
 381
 382   MergeableConst16Section =
 383       Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
 384                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 16);
 385
 386   MergeableConst32Section =
 387       Ctx->getELFSection(".rodata.cst32", ELF::SHT_PROGBITS,
 388                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 32);
 389
 390   // Exception Handling Sections.
 391
 392   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
 393   // it contains relocatable pointers.  In PIC mode, this is probably a big
 394   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
 395   // adjusted or this should be a data section.
 396   LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
 397                                    ELF::SHF_ALLOC);
 398
 399   COFFDebugSymbolsSection = nullptr;
 400   COFFDebugTypesSection = nullptr;
 401
 402   unsigned DebugSecType = ELF::SHT_PROGBITS;
 403
 404   // MIPS .debug_* sections should have SHT_MIPS_DWARF section type
 405   // to distinguish among sections contain DWARF and ECOFF debug formats.
 406   // Sections with ECOFF debug format are obsoleted and marked by SHT_PROGBITS.
 407   if (T.isMIPS())
 408     DebugSecType = ELF::SHT_MIPS_DWARF;
 409
 410   // Debug Info Sections.
 411   DwarfAbbrevSection =
 412       Ctx->getELFSection(".debug_abbrev", DebugSecType, 0);
 413   DwarfInfoSection = Ctx->getELFSection(".debug_info", DebugSecType, 0);
 414   DwarfLineSection = Ctx->getELFSection(".debug_line", DebugSecType, 0);
 415   DwarfLineStrSection =
 416       Ctx->getELFSection(".debug_line_str", DebugSecType,
 417                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1);
 418   DwarfFrameSection = Ctx->getELFSection(".debug_frame", DebugSecType, 0);
 419   DwarfPubNamesSection =
 420       Ctx->getELFSection(".debug_pubnames", DebugSecType, 0);
 421   DwarfPubTypesSection =
 422       Ctx->getELFSection(".debug_pubtypes", DebugSecType, 0);
 423   DwarfGnuPubNamesSection =
 424       Ctx->getELFSection(".debug_gnu_pubnames", DebugSecType, 0);
 425   DwarfGnuPubTypesSection =
 426       Ctx->getELFSection(".debug_gnu_pubtypes", DebugSecType, 0);
 427   DwarfStrSection =
 428       Ctx->getELFSection(".debug_str", DebugSecType,
 429                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1);
 430   DwarfLocSection = Ctx->getELFSection(".debug_loc", DebugSecType, 0);
 431   DwarfARangesSection =
 432       Ctx->getELFSection(".debug_aranges", DebugSecType, 0);
 433   DwarfRangesSection =
 434       Ctx->getELFSection(".debug_ranges", DebugSecType, 0);
 435   DwarfMacinfoSection =
 436       Ctx->getELFSection(".debug_macinfo", DebugSecType, 0);
 437   DwarfMacroSection = Ctx->getELFSection(".debug_macro", DebugSecType, 0);
 438
 439   // DWARF5 Experimental Debug Info
 440
 441   // Accelerator Tables
 442   DwarfDebugNamesSection =
 443       Ctx->getELFSection(".debug_names", ELF::SHT_PROGBITS, 0);
 444   DwarfAccelNamesSection =
 445       Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0);
 446   DwarfAccelObjCSection =
 447       Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0);
 448   DwarfAccelNamespaceSection =
 449       Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0);
 450   DwarfAccelTypesSection =
 451       Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0);
 452
 453   // String Offset and Address Sections
 454   DwarfStrOffSection =
 455       Ctx->getELFSection(".debug_str_offsets", DebugSecType, 0);
 456   DwarfAddrSection = Ctx->getELFSection(".debug_addr", DebugSecType, 0);
 457   DwarfRnglistsSection = Ctx->getELFSection(".debug_rnglists", DebugSecType, 0);
 458   DwarfLoclistsSection = Ctx->getELFSection(".debug_loclists", DebugSecType, 0);
 459
 460   // Fission Sections
 461   DwarfInfoDWOSection =
 462       Ctx->getELFSection(".debug_info.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 463   DwarfTypesDWOSection =
 464       Ctx->getELFSection(".debug_types.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 465   DwarfAbbrevDWOSection =
 466       Ctx->getELFSection(".debug_abbrev.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 467   DwarfStrDWOSection = Ctx->getELFSection(
 468       ".debug_str.dwo", DebugSecType,
 469       ELF::SHF_MERGE | ELF::SHF_STRINGS | ELF::SHF_EXCLUDE, 1);
 470   DwarfLineDWOSection =
 471       Ctx->getELFSection(".debug_line.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 472   DwarfLocDWOSection =
 473       Ctx->getELFSection(".debug_loc.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 474   DwarfStrOffDWOSection = Ctx->getELFSection(".debug_str_offsets.dwo",
 475                                              DebugSecType, ELF::SHF_EXCLUDE);
 476   DwarfRnglistsDWOSection =
 477       Ctx->getELFSection(".debug_rnglists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 478   DwarfMacinfoDWOSection =
 479       Ctx->getELFSection(".debug_macinfo.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 480   DwarfMacroDWOSection =
 481       Ctx->getELFSection(".debug_macro.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 482
 483   DwarfLoclistsDWOSection =
 484       Ctx->getELFSection(".debug_loclists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
 485
 486   // DWP Sections
 487   DwarfCUIndexSection =
 488       Ctx->getELFSection(".debug_cu_index", DebugSecType, 0);
 489   DwarfTUIndexSection =
 490       Ctx->getELFSection(".debug_tu_index", DebugSecType, 0);
 491
 492   StackMapSection =
 493       Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
 494
 495   FaultMapSection =
 496       Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
 497
 498   EHFrameSection =
 499       Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
 500
 501   StackSizesSection = Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, 0);
 502
 503   PseudoProbeSection = Ctx->getELFSection(".pseudo_probe", DebugSecType, 0);
 504   PseudoProbeDescSection =
 505       Ctx->getELFSection(".pseudo_probe_desc", DebugSecType, 0);
 506 }
 507
 508 void MCObjectFileInfo::initGOFFMCObjectFileInfo(const Triple &T) {
 509   TextSection = Ctx->getGOFFSection(".text", SectionKind::getText());
 510   BSSSection = Ctx->getGOFFSection(".bss", SectionKind::getBSS());
 511 }
 512
 513 void MCObjectFileInfo::initCOFFMCObjectFileInfo(const Triple &T) {
 514   EHFrameSection =
 515       Ctx->getCOFFSection(".eh_frame", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 516                                            COFF::IMAGE_SCN_MEM_READ,
 517                           SectionKind::getData());
 518
 519   // Set the `IMAGE_SCN_MEM_16BIT` flag when compiling for thumb mode.  This is
 520   // used to indicate to the linker that the text segment contains thumb instructions
 521   // and to set the ISA selection bit for calls accordingly.
 522   const bool IsThumb = T.getArch() == Triple::thumb;
 523
 524   CommDirectiveSupportsAlignment = true;
 525
 526   // COFF
 527   BSSSection = Ctx->getCOFFSection(
 528       ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
 529                   COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
 530       SectionKind::getBSS());
 531   TextSection = Ctx->getCOFFSection(
 532       ".text",
 533       (IsThumb ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) |
 534           COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
 535           COFF::IMAGE_SCN_MEM_READ,
 536       SectionKind::getText());
 537   DataSection = Ctx->getCOFFSection(
 538       ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
 539                    COFF::IMAGE_SCN_MEM_WRITE,
 540       SectionKind::getData());
 541   ReadOnlySection = Ctx->getCOFFSection(
 542       ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
 543       SectionKind::getReadOnly());
 544
 545   if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::aarch64) {
 546     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
 547     LSDASection = nullptr;
 548   } else {
 549     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
 550                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 551                                           COFF::IMAGE_SCN_MEM_READ,
 552                                       SectionKind::getReadOnly());
 553   }
 554
 555   // Debug info.
 556   COFFDebugSymbolsSection =
 557       Ctx->getCOFFSection(".debug$S", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
 558                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 559                                        COFF::IMAGE_SCN_MEM_READ),
 560                           SectionKind::getMetadata());
 561   COFFDebugTypesSection =
 562       Ctx->getCOFFSection(".debug$T", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
 563                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 564                                        COFF::IMAGE_SCN_MEM_READ),
 565                           SectionKind::getMetadata());
 566   COFFGlobalTypeHashesSection = Ctx->getCOFFSection(
 567       ".debug$H",
 568       (COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 569        COFF::IMAGE_SCN_MEM_READ),
 570       SectionKind::getMetadata());
 571
 572   DwarfAbbrevSection = Ctx->getCOFFSection(
 573       ".debug_abbrev",
 574       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 575           COFF::IMAGE_SCN_MEM_READ,
 576       SectionKind::getMetadata(), "section_abbrev");
 577   DwarfInfoSection = Ctx->getCOFFSection(
 578       ".debug_info",
 579       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 580           COFF::IMAGE_SCN_MEM_READ,
 581       SectionKind::getMetadata(), "section_info");
 582   DwarfLineSection = Ctx->getCOFFSection(
 583       ".debug_line",
 584       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 585           COFF::IMAGE_SCN_MEM_READ,
 586       SectionKind::getMetadata(), "section_line");
 587   DwarfLineStrSection = Ctx->getCOFFSection(
 588       ".debug_line_str",
 589       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 590           COFF::IMAGE_SCN_MEM_READ,
 591       SectionKind::getMetadata(), "section_line_str");
 592   DwarfFrameSection = Ctx->getCOFFSection(
 593       ".debug_frame",
 594       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 595           COFF::IMAGE_SCN_MEM_READ,
 596       SectionKind::getMetadata());
 597   DwarfPubNamesSection = Ctx->getCOFFSection(
 598       ".debug_pubnames",
 599       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 600           COFF::IMAGE_SCN_MEM_READ,
 601       SectionKind::getMetadata());
 602   DwarfPubTypesSection = Ctx->getCOFFSection(
 603       ".debug_pubtypes",
 604       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 605           COFF::IMAGE_SCN_MEM_READ,
 606       SectionKind::getMetadata());
 607   DwarfGnuPubNamesSection = Ctx->getCOFFSection(
 608       ".debug_gnu_pubnames",
 609       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 610           COFF::IMAGE_SCN_MEM_READ,
 611       SectionKind::getMetadata());
 612   DwarfGnuPubTypesSection = Ctx->getCOFFSection(
 613       ".debug_gnu_pubtypes",
 614       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 615           COFF::IMAGE_SCN_MEM_READ,
 616       SectionKind::getMetadata());
 617   DwarfStrSection = Ctx->getCOFFSection(
 618       ".debug_str",
 619       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 620           COFF::IMAGE_SCN_MEM_READ,
 621       SectionKind::getMetadata(), "info_string");
 622   DwarfStrOffSection = Ctx->getCOFFSection(
 623       ".debug_str_offsets",
 624       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 625           COFF::IMAGE_SCN_MEM_READ,
 626       SectionKind::getMetadata(), "section_str_off");
 627   DwarfLocSection = Ctx->getCOFFSection(
 628       ".debug_loc",
 629       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 630           COFF::IMAGE_SCN_MEM_READ,
 631       SectionKind::getMetadata(), "section_debug_loc");
 632   DwarfLoclistsSection = Ctx->getCOFFSection(
 633       ".debug_loclists",
 634       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 635           COFF::IMAGE_SCN_MEM_READ,
 636       SectionKind::getMetadata(), "section_debug_loclists");
 637   DwarfARangesSection = Ctx->getCOFFSection(
 638       ".debug_aranges",
 639       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 640           COFF::IMAGE_SCN_MEM_READ,
 641       SectionKind::getMetadata());
 642   DwarfRangesSection = Ctx->getCOFFSection(
 643       ".debug_ranges",
 644       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 645           COFF::IMAGE_SCN_MEM_READ,
 646       SectionKind::getMetadata(), "debug_range");
 647   DwarfRnglistsSection = Ctx->getCOFFSection(
 648       ".debug_rnglists",
 649       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 650           COFF::IMAGE_SCN_MEM_READ,
 651       SectionKind::getMetadata(), "debug_rnglists");
 652   DwarfMacinfoSection = Ctx->getCOFFSection(
 653       ".debug_macinfo",
 654       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 655           COFF::IMAGE_SCN_MEM_READ,
 656       SectionKind::getMetadata(), "debug_macinfo");
 657   DwarfMacroSection = Ctx->getCOFFSection(
 658       ".debug_macro",
 659       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 660           COFF::IMAGE_SCN_MEM_READ,
 661       SectionKind::getMetadata(), "debug_macro");
 662   DwarfMacinfoDWOSection = Ctx->getCOFFSection(
 663       ".debug_macinfo.dwo",
 664       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 665           COFF::IMAGE_SCN_MEM_READ,
 666       SectionKind::getMetadata(), "debug_macinfo.dwo");
 667   DwarfMacroDWOSection = Ctx->getCOFFSection(
 668       ".debug_macro.dwo",
 669       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 670           COFF::IMAGE_SCN_MEM_READ,
 671       SectionKind::getMetadata(), "debug_macro.dwo");
 672   DwarfInfoDWOSection = Ctx->getCOFFSection(
 673       ".debug_info.dwo",
 674       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 675           COFF::IMAGE_SCN_MEM_READ,
 676       SectionKind::getMetadata(), "section_info_dwo");
 677   DwarfTypesDWOSection = Ctx->getCOFFSection(
 678       ".debug_types.dwo",
 679       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 680           COFF::IMAGE_SCN_MEM_READ,
 681       SectionKind::getMetadata(), "section_types_dwo");
 682   DwarfAbbrevDWOSection = Ctx->getCOFFSection(
 683       ".debug_abbrev.dwo",
 684       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 685           COFF::IMAGE_SCN_MEM_READ,
 686       SectionKind::getMetadata(), "section_abbrev_dwo");
 687   DwarfStrDWOSection = Ctx->getCOFFSection(
 688       ".debug_str.dwo",
 689       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 690           COFF::IMAGE_SCN_MEM_READ,
 691       SectionKind::getMetadata(), "skel_string");
 692   DwarfLineDWOSection = Ctx->getCOFFSection(
 693       ".debug_line.dwo",
 694       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 695           COFF::IMAGE_SCN_MEM_READ,
 696       SectionKind::getMetadata());
 697   DwarfLocDWOSection = Ctx->getCOFFSection(
 698       ".debug_loc.dwo",
 699       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 700           COFF::IMAGE_SCN_MEM_READ,
 701       SectionKind::getMetadata(), "skel_loc");
 702   DwarfStrOffDWOSection = Ctx->getCOFFSection(
 703       ".debug_str_offsets.dwo",
 704       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 705           COFF::IMAGE_SCN_MEM_READ,
 706       SectionKind::getMetadata(), "section_str_off_dwo");
 707   DwarfAddrSection = Ctx->getCOFFSection(
 708       ".debug_addr",
 709       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 710           COFF::IMAGE_SCN_MEM_READ,
 711       SectionKind::getMetadata(), "addr_sec");
 712   DwarfCUIndexSection = Ctx->getCOFFSection(
 713       ".debug_cu_index",
 714       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 715           COFF::IMAGE_SCN_MEM_READ,
 716       SectionKind::getMetadata());
 717   DwarfTUIndexSection = Ctx->getCOFFSection(
 718       ".debug_tu_index",
 719       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 720           COFF::IMAGE_SCN_MEM_READ,
 721       SectionKind::getMetadata());
 722   DwarfDebugNamesSection = Ctx->getCOFFSection(
 723       ".debug_names",
 724       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 725           COFF::IMAGE_SCN_MEM_READ,
 726       SectionKind::getMetadata(), "debug_names_begin");
 727   DwarfAccelNamesSection = Ctx->getCOFFSection(
 728       ".apple_names",
 729       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 730           COFF::IMAGE_SCN_MEM_READ,
 731       SectionKind::getMetadata(), "names_begin");
 732   DwarfAccelNamespaceSection = Ctx->getCOFFSection(
 733       ".apple_namespaces",
 734       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 735           COFF::IMAGE_SCN_MEM_READ,
 736       SectionKind::getMetadata(), "namespac_begin");
 737   DwarfAccelTypesSection = Ctx->getCOFFSection(
 738       ".apple_types",
 739       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 740           COFF::IMAGE_SCN_MEM_READ,
 741       SectionKind::getMetadata(), "types_begin");
 742   DwarfAccelObjCSection = Ctx->getCOFFSection(
 743       ".apple_objc",
 744       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 745           COFF::IMAGE_SCN_MEM_READ,
 746       SectionKind::getMetadata(), "objc_begin");
 747
 748   DrectveSection = Ctx->getCOFFSection(
 749       ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
 750       SectionKind::getMetadata());
 751
 752   PDataSection = Ctx->getCOFFSection(
 753       ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
 754       SectionKind::getData());
 755
 756   XDataSection = Ctx->getCOFFSection(
 757       ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
 758       SectionKind::getData());
 759
 760   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
 761                                       SectionKind::getMetadata());
 762
 763   GEHContSection = Ctx->getCOFFSection(".gehcont$y",
 764                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 765                                            COFF::IMAGE_SCN_MEM_READ,
 766                                        SectionKind::getMetadata());
 767
 768   GFIDsSection = Ctx->getCOFFSection(".gfids$y",
 769                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 770                                          COFF::IMAGE_SCN_MEM_READ,
 771                                      SectionKind::getMetadata());
 772
 773   GIATsSection = Ctx->getCOFFSection(".giats$y",
 774                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 775                                          COFF::IMAGE_SCN_MEM_READ,
 776                                      SectionKind::getMetadata());
 777
 778   GLJMPSection = Ctx->getCOFFSection(".gljmp$y",
 779                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 780                                          COFF::IMAGE_SCN_MEM_READ,
 781                                      SectionKind::getMetadata());
 782
 783   TLSDataSection = Ctx->getCOFFSection(
 784       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
 785                    COFF::IMAGE_SCN_MEM_WRITE,
 786       SectionKind::getData());
 787
 788   StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
 789                                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
 790                                             COFF::IMAGE_SCN_MEM_READ,
 791                                         SectionKind::getReadOnly());
 792 }
 793
 794 void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
 795   TextSection = Ctx->getWasmSection(".text", SectionKind::getText());
 796   DataSection = Ctx->getWasmSection(".data", SectionKind::getData());
 797
 798   DwarfLineSection =
 799       Ctx->getWasmSection(".debug_line", SectionKind::getMetadata());
 800   DwarfLineStrSection =
 801       Ctx->getWasmSection(".debug_line_str", SectionKind::getMetadata(),
 802                           wasm::WASM_SEG_FLAG_STRINGS);
 803   DwarfStrSection = Ctx->getWasmSection(
 804       ".debug_str", SectionKind::getMetadata(), wasm::WASM_SEG_FLAG_STRINGS);
 805   DwarfLocSection =
 806       Ctx->getWasmSection(".debug_loc", SectionKind::getMetadata());
 807   DwarfAbbrevSection =
 808       Ctx->getWasmSection(".debug_abbrev", SectionKind::getMetadata());
 809   DwarfARangesSection = Ctx->getWasmSection(".debug_aranges", SectionKind::getMetadata());
 810   DwarfRangesSection =
 811       Ctx->getWasmSection(".debug_ranges", SectionKind::getMetadata());
 812   DwarfMacinfoSection =
 813       Ctx->getWasmSection(".debug_macinfo", SectionKind::getMetadata());
 814   DwarfMacroSection =
 815       Ctx->getWasmSection(".debug_macro", SectionKind::getMetadata());
 816   DwarfCUIndexSection = Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
 817   DwarfTUIndexSection = Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
 818   DwarfInfoSection =
 819       Ctx->getWasmSection(".debug_info", SectionKind::getMetadata());
 820   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", SectionKind::getMetadata());
 821   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", SectionKind::getMetadata());
 822   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", SectionKind::getMetadata());
 823   DwarfGnuPubNamesSection =
 824       Ctx->getWasmSection(".debug_gnu_pubnames", SectionKind::getMetadata());
 825   DwarfGnuPubTypesSection =
 826       Ctx->getWasmSection(".debug_gnu_pubtypes", SectionKind::getMetadata());
 827
 828   DwarfDebugNamesSection =
 829       Ctx->getWasmSection(".debug_names", SectionKind::getMetadata());
 830   DwarfStrOffSection =
 831       Ctx->getWasmSection(".debug_str_offsets", SectionKind::getMetadata());
 832   DwarfAddrSection =
 833       Ctx->getWasmSection(".debug_addr", SectionKind::getMetadata());
 834   DwarfRnglistsSection =
 835       Ctx->getWasmSection(".debug_rnglists", SectionKind::getMetadata());
 836   DwarfLoclistsSection =
 837       Ctx->getWasmSection(".debug_loclists", SectionKind::getMetadata());
 838
 839   // Fission Sections
 840   DwarfInfoDWOSection =
 841       Ctx->getWasmSection(".debug_info.dwo", SectionKind::getMetadata());
 842   DwarfTypesDWOSection =
 843       Ctx->getWasmSection(".debug_types.dwo", SectionKind::getMetadata());
 844   DwarfAbbrevDWOSection =
 845       Ctx->getWasmSection(".debug_abbrev.dwo", SectionKind::getMetadata());
 846   DwarfStrDWOSection =
 847       Ctx->getWasmSection(".debug_str.dwo", SectionKind::getMetadata(),
 848                           wasm::WASM_SEG_FLAG_STRINGS);
 849   DwarfLineDWOSection =
 850       Ctx->getWasmSection(".debug_line.dwo", SectionKind::getMetadata());
 851   DwarfLocDWOSection =
 852       Ctx->getWasmSection(".debug_loc.dwo", SectionKind::getMetadata());
 853   DwarfStrOffDWOSection =
 854       Ctx->getWasmSection(".debug_str_offsets.dwo", SectionKind::getMetadata());
 855   DwarfRnglistsDWOSection =
 856       Ctx->getWasmSection(".debug_rnglists.dwo", SectionKind::getMetadata());
 857   DwarfMacinfoDWOSection =
 858       Ctx->getWasmSection(".debug_macinfo.dwo", SectionKind::getMetadata());
 859   DwarfMacroDWOSection =
 860       Ctx->getWasmSection(".debug_macro.dwo", SectionKind::getMetadata());
 861
 862   DwarfLoclistsDWOSection =
 863       Ctx->getWasmSection(".debug_loclists.dwo", SectionKind::getMetadata());
 864
 865   // DWP Sections
 866   DwarfCUIndexSection =
 867       Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
 868   DwarfTUIndexSection =
 869       Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
 870
 871   // Wasm use data section for LSDA.
 872   // TODO Consider putting each function's exception table in a separate
 873   // section, as in -function-sections, to facilitate lld's --gc-section.
 874   LSDASection = Ctx->getWasmSection(".rodata.gcc_except_table",
 875                                     SectionKind::getReadOnlyWithRel());
 876
 877   // TODO: Define more sections.
 878 }
 879
 880 void MCObjectFileInfo::initXCOFFMCObjectFileInfo(const Triple &T) {
 881   // The default csect for program code. Functions without a specified section
 882   // get placed into this csect. The choice of csect name is not a property of
 883   // the ABI or object file format. For example, the XL compiler uses an unnamed
 884   // csect for program code.
 885   TextSection = Ctx->getXCOFFSection(
 886       ".text", SectionKind::getText(),
 887       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_PR, XCOFF::XTY_SD),
 888       /* MultiSymbolsAllowed*/ true);
 889
 890   DataSection = Ctx->getXCOFFSection(
 891       ".data", SectionKind::getData(),
 892       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW, XCOFF::XTY_SD),
 893       /* MultiSymbolsAllowed*/ true);
 894
 895   ReadOnlySection = Ctx->getXCOFFSection(
 896       ".rodata", SectionKind::getReadOnly(),
 897       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
 898       /* MultiSymbolsAllowed*/ true);
 899   ReadOnlySection->setAlignment(Align(4));
 900
 901   ReadOnly8Section = Ctx->getXCOFFSection(
 902       ".rodata.8", SectionKind::getReadOnly(),
 903       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
 904       /* MultiSymbolsAllowed*/ true);
 905   ReadOnly8Section->setAlignment(Align(8));
 906
 907   ReadOnly16Section = Ctx->getXCOFFSection(
 908       ".rodata.16", SectionKind::getReadOnly(),
 909       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
 910       /* MultiSymbolsAllowed*/ true);
 911   ReadOnly16Section->setAlignment(Align(16));
 912
 913   TLSDataSection = Ctx->getXCOFFSection(
 914       ".tdata", SectionKind::getThreadData(),
 915       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TL, XCOFF::XTY_SD),
 916       /* MultiSymbolsAllowed*/ true);
 917
 918   TOCBaseSection = Ctx->getXCOFFSection(
 919       "TOC", SectionKind::getData(),
 920       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TC0,
 921                              XCOFF::XTY_SD));
 922
 923   // The TOC-base always has 0 size, but 4 byte alignment.
 924   TOCBaseSection->setAlignment(Align(4));
 925
 926   LSDASection = Ctx->getXCOFFSection(
 927       ".gcc_except_table", SectionKind::getReadOnly(),
 928       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO,
 929                              XCOFF::XTY_SD));
 930
 931   CompactUnwindSection = Ctx->getXCOFFSection(
 932       ".eh_info_table", SectionKind::getData(),
 933       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW,
 934                              XCOFF::XTY_SD));
 935
 936   // DWARF sections for XCOFF are not csects. They are special STYP_DWARF
 937   // sections, and the individual DWARF sections are distinguished by their
 938   // section subtype.
 939   DwarfAbbrevSection = Ctx->getXCOFFSection(
 940       ".dwabrev", SectionKind::getMetadata(), /* CsectProperties */ None,
 941       /* MultiSymbolsAllowed */ true, ".dwabrev", XCOFF::SSUBTYP_DWABREV);
 942
 943   DwarfInfoSection = Ctx->getXCOFFSection(
 944       ".dwinfo", SectionKind::getMetadata(), /* CsectProperties */ None,
 945       /* MultiSymbolsAllowed */ true, ".dwinfo", XCOFF::SSUBTYP_DWINFO);
 946
 947   DwarfLineSection = Ctx->getXCOFFSection(
 948       ".dwline", SectionKind::getMetadata(), /* CsectProperties */ None,
 949       /* MultiSymbolsAllowed */ true, ".dwline", XCOFF::SSUBTYP_DWLINE);
 950
 951   DwarfFrameSection = Ctx->getXCOFFSection(
 952       ".dwframe", SectionKind::getMetadata(), /* CsectProperties */ None,
 953       /* MultiSymbolsAllowed */ true, ".dwframe", XCOFF::SSUBTYP_DWFRAME);
 954
 955   DwarfPubNamesSection = Ctx->getXCOFFSection(
 956       ".dwpbnms", SectionKind::getMetadata(), /* CsectProperties */ None,
 957       /* MultiSymbolsAllowed */ true, ".dwpbnms", XCOFF::SSUBTYP_DWPBNMS);
 958
 959   DwarfPubTypesSection = Ctx->getXCOFFSection(
 960       ".dwpbtyp", SectionKind::getMetadata(), /* CsectProperties */ None,
 961       /* MultiSymbolsAllowed */ true, ".dwpbtyp", XCOFF::SSUBTYP_DWPBTYP);
 962
 963   DwarfStrSection = Ctx->getXCOFFSection(
 964       ".dwstr", SectionKind::getMetadata(), /* CsectProperties */ None,
 965       /* MultiSymbolsAllowed */ true, ".dwstr", XCOFF::SSUBTYP_DWSTR);
 966
 967   DwarfLocSection = Ctx->getXCOFFSection(
 968       ".dwloc", SectionKind::getMetadata(), /* CsectProperties */ None,
 969       /* MultiSymbolsAllowed */ true, ".dwloc", XCOFF::SSUBTYP_DWLOC);
 970
 971   DwarfARangesSection = Ctx->getXCOFFSection(
 972       ".dwarnge", SectionKind::getMetadata(), /* CsectProperties */ None,
 973       /* MultiSymbolsAllowed */ true, ".dwarnge", XCOFF::SSUBTYP_DWARNGE);
 974
 975   DwarfRangesSection = Ctx->getXCOFFSection(
 976       ".dwrnges", SectionKind::getMetadata(), /* CsectProperties */ None,
 977       /* MultiSymbolsAllowed */ true, ".dwrnges", XCOFF::SSUBTYP_DWRNGES);
 978
 979   DwarfMacinfoSection = Ctx->getXCOFFSection(
 980       ".dwmac", SectionKind::getMetadata(), /* CsectProperties */ None,
 981       /* MultiSymbolsAllowed */ true, ".dwmac", XCOFF::SSUBTYP_DWMAC);
 982 }
 983
 984 void MCObjectFileInfo::initMCObjectFileInfo(MCContext &MCCtx, bool PIC,
 985                                             bool LargeCodeModel) {
 986   PositionIndependent = PIC;
 987   Ctx = &MCCtx;
 988
 989   // Common.
 990   CommDirectiveSupportsAlignment = true;
 991   SupportsWeakOmittedEHFrame = true;
 992   SupportsCompactUnwindWithoutEHFrame = false;
 993   OmitDwarfIfHaveCompactUnwind = false;
 994
 995   FDECFIEncoding = dwarf::DW_EH_PE_absptr;
 996
 997   CompactUnwindDwarfEHFrameOnly = 0;
 998
 999   EHFrameSection = nullptr;             // Created on demand.
1000   CompactUnwindSection = nullptr;       // Used only by selected targets.
1001   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
1002   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
1003   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
1004   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
1005
1006   Triple TheTriple = Ctx->getTargetTriple();
1007   switch (Ctx->getObjectFileType()) {
1008   case MCContext::IsMachO:
1009     initMachOMCObjectFileInfo(TheTriple);
1010     break;
1011   case MCContext::IsCOFF:
1012     initCOFFMCObjectFileInfo(TheTriple);
1013     break;
1014   case MCContext::IsELF:
1015     initELFMCObjectFileInfo(TheTriple, LargeCodeModel);
1016     break;
1017   case MCContext::IsGOFF:
1018     initGOFFMCObjectFileInfo(TheTriple);
1019     break;
1020   case MCContext::IsWasm:
1021     initWasmMCObjectFileInfo(TheTriple);
1022     break;
1023   case MCContext::IsXCOFF:
1024     initXCOFFMCObjectFileInfo(TheTriple);
1025     break;
1026   }
1027 }
1028
1029 MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
1030                                                    uint64_t Hash) const {
1031   switch (Ctx->getTargetTriple().getObjectFormat()) {
1032   case Triple::ELF:
1033     return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0,
1034                               utostr(Hash), /*IsComdat=*/true);
1035   case Triple::Wasm:
1036     return Ctx->getWasmSection(Name, SectionKind::getMetadata(), 0,
1037                                utostr(Hash), MCContext::GenericSectionID);
1038   case Triple::MachO:
1039   case Triple::COFF:
1040   case Triple::GOFF:
1041   case Triple::XCOFF:
1042   case Triple::UnknownObjectFormat:
1043     report_fatal_error("Cannot get DWARF comdat section for this object file "
1044                        "format: not implemented.");
1045     break;
1046   }
1047   llvm_unreachable("Unknown ObjectFormatType");
1048 }
1049
1050 MCSection *
1051 MCObjectFileInfo::getStackSizesSection(const MCSection &TextSec) const {
1052   if (Ctx->getObjectFileType() != MCContext::IsELF)
1053     return StackSizesSection;
1054
1055   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1056   unsigned Flags = ELF::SHF_LINK_ORDER;
1057   StringRef GroupName;
1058   if (const MCSymbol *Group = ElfSec.getGroup()) {
1059     GroupName = Group->getName();
1060     Flags |= ELF::SHF_GROUP;
1061   }
1062
1063   return Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, Flags, 0,
1064                             GroupName, true, ElfSec.getUniqueID(),
1065                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1066 }
1067
1068 MCSection *
1069 MCObjectFileInfo::getBBAddrMapSection(const MCSection &TextSec) const {
1070   if (Ctx->getObjectFileType() != MCContext::IsELF)
1071     return nullptr;
1072
1073   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1074   unsigned Flags = ELF::SHF_LINK_ORDER;
1075   StringRef GroupName;
1076   if (const MCSymbol *Group = ElfSec.getGroup()) {
1077     GroupName = Group->getName();
1078     Flags |= ELF::SHF_GROUP;
1079   }
1080
1081   // Use the text section's begin symbol and unique ID to create a separate
1082   // .llvm_bb_addr_map section associated with every unique text section.
1083   return Ctx->getELFSection(".llvm_bb_addr_map", ELF::SHT_LLVM_BB_ADDR_MAP,
1084                             Flags, 0, GroupName, true, ElfSec.getUniqueID(),
1085                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1086 }
1087
1088 MCSection *
1089 MCObjectFileInfo::getPseudoProbeSection(const MCSection *TextSec) const {
1090   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1091     const auto *ElfSec = static_cast<const MCSectionELF *>(TextSec);
1092     // Create a separate section for probes that comes with a comdat function.
1093     if (const MCSymbol *Group = ElfSec->getGroup()) {
1094       auto *S = static_cast<MCSectionELF *>(PseudoProbeSection);
1095       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1096       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1097                                 S->getEntrySize(), Group->getName(),
1098                                 /*IsComdat=*/true);
1099     }
1100   }
1101   return PseudoProbeSection;
1102 }
1103
1104 MCSection *
1105 MCObjectFileInfo::getPseudoProbeDescSection(StringRef FuncName) const {
1106   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1107     // Create a separate comdat group for each function's descriptor in order
1108     // for the linker to deduplicate. The duplication, must be from different
1109     // tranlation unit, can come from:
1110     //  1. Inline functions defined in header files;
1111     //  2. ThinLTO imported funcions;
1112     //  3. Weak-linkage definitions.
1113     // Use a concatenation of the section name and the function name as the
1114     // group name so that descriptor-only groups won't be folded with groups of
1115     // code.
1116     if (Ctx->getTargetTriple().supportsCOMDAT() && !FuncName.empty()) {
1117       auto *S = static_cast<MCSectionELF *>(PseudoProbeDescSection);
1118       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1119       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1120                                 S->getEntrySize(),
1121                                 S->getName() + "_" + FuncName,
1122                                 /*IsComdat=*/true);
1123     }
1124   }
1125   return PseudoProbeDescSection;
1126 }