DirectXShaderCompiler/lib/MC/MCObjectFileInfo.cpp

//===-- MObjectFileInfo.cpp - Object File Information ---------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSectionCOFF.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSectionMachO.h"
using namespace llvm;

static bool useCompactUnwind(const Triple &T) {
  // Only on darwin.
  if (!T.isOSDarwin())
    return false;

  // aarch64 always has it.
  if (T.getArch() == Triple::aarch64)
    return true;

  // Use it on newer version of OS X.
  if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
    return true;

  // And the iOS simulator.
  if (T.isiOS() &&
      (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86))
    return true;

  return false;
}

void MCObjectFileInfo::initMachOMCObjectFileInfo(Triple T) {
  // MachO
  SupportsWeakOmittedEHFrame = false;

  if (T.isOSDarwin() && T.getArch() == Triple::aarch64)
    SupportsCompactUnwindWithoutEHFrame = true;

  PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel
    | dwarf::DW_EH_PE_sdata4;
  LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
  TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
    dwarf::DW_EH_PE_sdata4;

  // .comm doesn't support alignment before Leopard.
  if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
    CommDirectiveSupportsAlignment = false;

  TextSection // .text
    = Ctx->getMachOSection("__TEXT", "__text",
                           MachO::S_ATTR_PURE_INSTRUCTIONS,
                           SectionKind::getText());
  DataSection // .data
    = Ctx->getMachOSection("__DATA", "__data", 0,
                           SectionKind::getDataRel());

  // BSSSection might not be expected initialized on msvc.
  BSSSection = nullptr;

  TLSDataSection // .tdata
    = Ctx->getMachOSection("__DATA", "__thread_data",
                           MachO::S_THREAD_LOCAL_REGULAR,
                           SectionKind::getDataRel());
  TLSBSSSection // .tbss
    = Ctx->getMachOSection("__DATA", "__thread_bss",
                           MachO::S_THREAD_LOCAL_ZEROFILL,
                           SectionKind::getThreadBSS());

  // TODO: Verify datarel below.
  TLSTLVSection // .tlv
    = Ctx->getMachOSection("__DATA", "__thread_vars",
                           MachO::S_THREAD_LOCAL_VARIABLES,
                           SectionKind::getDataRel());

  TLSThreadInitSection
    = Ctx->getMachOSection("__DATA", "__thread_init",
                          MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
                          SectionKind::getDataRel());

  CStringSection // .cstring
    = Ctx->getMachOSection("__TEXT", "__cstring",
                           MachO::S_CSTRING_LITERALS,
                           SectionKind::getMergeable1ByteCString());
  UStringSection
    = Ctx->getMachOSection("__TEXT","__ustring", 0,
                           SectionKind::getMergeable2ByteCString());
  FourByteConstantSection // .literal4
    = Ctx->getMachOSection("__TEXT", "__literal4",
                           MachO::S_4BYTE_LITERALS,
                           SectionKind::getMergeableConst4());
  EightByteConstantSection // .literal8
    = Ctx->getMachOSection("__TEXT", "__literal8",
                           MachO::S_8BYTE_LITERALS,
                           SectionKind::getMergeableConst8());

  SixteenByteConstantSection // .literal16
      = Ctx->getMachOSection("__TEXT", "__literal16",
                             MachO::S_16BYTE_LITERALS,
                             SectionKind::getMergeableConst16());

  ReadOnlySection  // .const
    = Ctx->getMachOSection("__TEXT", "__const", 0,
                           SectionKind::getReadOnly());

  TextCoalSection
    = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
                           MachO::S_COALESCED |
                           MachO::S_ATTR_PURE_INSTRUCTIONS,
                           SectionKind::getText());
  ConstTextCoalSection
    = Ctx->getMachOSection("__TEXT", "__const_coal",
                           MachO::S_COALESCED,
                           SectionKind::getReadOnly());
  ConstDataSection  // .const_data
    = Ctx->getMachOSection("__DATA", "__const", 0,
                           SectionKind::getReadOnlyWithRel());
  DataCoalSection
    = Ctx->getMachOSection("__DATA","__datacoal_nt",
                           MachO::S_COALESCED,
                           SectionKind::getDataRel());
  DataCommonSection
    = Ctx->getMachOSection("__DATA","__common",
                           MachO::S_ZEROFILL,
                           SectionKind::getBSS());
  DataBSSSection
    = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
                           SectionKind::getBSS());


  LazySymbolPointerSection
    = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
                           MachO::S_LAZY_SYMBOL_POINTERS,
                           SectionKind::getMetadata());
  NonLazySymbolPointerSection
    = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
                           MachO::S_NON_LAZY_SYMBOL_POINTERS,
                           SectionKind::getMetadata());

  if (RelocM == Reloc::Static) {
    StaticCtorSection
      = Ctx->getMachOSection("__TEXT", "__constructor", 0,
                             SectionKind::getDataRel());
    StaticDtorSection
      = Ctx->getMachOSection("__TEXT", "__destructor", 0,
                             SectionKind::getDataRel());
  } else {
    StaticCtorSection
      = Ctx->getMachOSection("__DATA", "__mod_init_func",
                             MachO::S_MOD_INIT_FUNC_POINTERS,
                             SectionKind::getDataRel());
    StaticDtorSection
      = Ctx->getMachOSection("__DATA", "__mod_term_func",
                             MachO::S_MOD_TERM_FUNC_POINTERS,
                             SectionKind::getDataRel());
  }

  // Exception Handling.
  LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
                                     SectionKind::getReadOnlyWithRel());

  COFFDebugSymbolsSection = nullptr;

  if (useCompactUnwind(T)) {
    CompactUnwindSection =
        Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
                             SectionKind::getReadOnly());

    if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)
      CompactUnwindDwarfEHFrameOnly = 0x04000000;
    else if (T.getArch() == Triple::aarch64)
      CompactUnwindDwarfEHFrameOnly = 0x03000000;
  }

  // Debug Information.
  DwarfAccelNamesSection =
      Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "names_begin");
  DwarfAccelObjCSection =
      Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "objc_begin");
  // 16 character section limit...
  DwarfAccelNamespaceSection =
      Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "namespac_begin");
  DwarfAccelTypesSection =
      Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "types_begin");

  DwarfAbbrevSection =
      Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "section_abbrev");
  DwarfInfoSection =
      Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "section_info");
  DwarfLineSection =
      Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "section_line");
  DwarfFrameSection =
      Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfPubNamesSection =
      Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfPubTypesSection =
      Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfGnuPubNamesSection =
      Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfGnuPubTypesSection =
      Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfStrSection =
      Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "info_string");
  DwarfLocSection =
      Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "section_debug_loc");
  DwarfARangesSection =
      Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  DwarfRangesSection =
      Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata(), "debug_range");
  DwarfDebugInlineSection =
      Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG,
                           SectionKind::getMetadata());
  StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
                                         0, SectionKind::getMetadata());

  FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
                                         0, SectionKind::getMetadata());

  TLSExtraDataSection = TLSTLVSection;
}

void MCObjectFileInfo::initELFMCObjectFileInfo(Triple T) {
  switch (T.getArch()) {
  case Triple::mips:
  case Triple::mipsel:
    FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
    break;
  case Triple::mips64:
  case Triple::mips64el:
    FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
    break;
  case Triple::x86_64:
    FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
                     ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8
                                                    : dwarf::DW_EH_PE_sdata4);

    break;
  default:
    FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
    break;
  }

  switch (T.getArch()) {
  case Triple::arm:
  case Triple::armeb:
  case Triple::thumb:
  case Triple::thumbeb:
    if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
      break;
    // Fallthrough if not using EHABI
  case Triple::ppc:
  case Triple::x86:
    PersonalityEncoding = (RelocM == Reloc::PIC_)
     ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
     : dwarf::DW_EH_PE_absptr;
    LSDAEncoding = (RelocM == Reloc::PIC_)
      ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
      : dwarf::DW_EH_PE_absptr;
    TTypeEncoding = (RelocM == Reloc::PIC_)
     ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
     : dwarf::DW_EH_PE_absptr;
    break;
  case Triple::x86_64:
    if (RelocM == Reloc::PIC_) {
      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
      LSDAEncoding = dwarf::DW_EH_PE_pcrel |
        (CMModel == CodeModel::Small
         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
    } else {
      PersonalityEncoding =
        (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
      LSDAEncoding = (CMModel == CodeModel::Small)
        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
      TTypeEncoding = (CMModel == CodeModel::Small)
        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
    }
    break;
  case Triple::aarch64:
  case Triple::aarch64_be:
    // The small model guarantees static code/data size < 4GB, but not where it
    // will be in memory. Most of these could end up >2GB away so even a signed
    // pc-relative 32-bit address is insufficient, theoretically.
    if (RelocM == Reloc::PIC_) {
      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata8;
      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata8;
    } else {
      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
      LSDAEncoding = dwarf::DW_EH_PE_absptr;
      TTypeEncoding = dwarf::DW_EH_PE_absptr;
    }
    break;
  case Triple::mips:
  case Triple::mipsel:
  case Triple::mips64:
  case Triple::mips64el:
    // MIPS uses indirect pointer to refer personality functions and types, so
    // that the eh_frame section can be read-only. DW.ref.personality will be
    // generated for relocation.
    PersonalityEncoding = dwarf::DW_EH_PE_indirect;
    // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't
    //        identify N64 from just a triple.
    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
                    dwarf::DW_EH_PE_sdata4;
    // We don't support PC-relative LSDA references in GAS so we use the default
    // DW_EH_PE_absptr for those.
    break;
  case Triple::ppc64:
  case Triple::ppc64le:
    PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
      dwarf::DW_EH_PE_udata8;
    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
      dwarf::DW_EH_PE_udata8;
    break;
  case Triple::sparcel:
  case Triple::sparc:
    if (RelocM == Reloc::PIC_) {
      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
    } else {
      LSDAEncoding = dwarf::DW_EH_PE_absptr;
      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
      TTypeEncoding = dwarf::DW_EH_PE_absptr;
    }
    break;
  case Triple::sparcv9:
    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
    if (RelocM == Reloc::PIC_) {
      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
    } else {
      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
      TTypeEncoding = dwarf::DW_EH_PE_absptr;
    }
    break;
  case Triple::systemz:
    // All currently-defined code models guarantee that 4-byte PC-relative
    // values will be in range.
    if (RelocM == Reloc::PIC_) {
      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
        dwarf::DW_EH_PE_sdata4;
    } else {
      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
      LSDAEncoding = dwarf::DW_EH_PE_absptr;
      TTypeEncoding = dwarf::DW_EH_PE_absptr;
    }
    break;
  default:
    break;
  }

  // Solaris requires different flags for .eh_frame to seemingly every other
  // platform.
  EHSectionType = ELF::SHT_PROGBITS;
  EHSectionFlags = ELF::SHF_ALLOC;
  if (T.isOSSolaris()) {
    if (T.getArch() == Triple::x86_64)
      EHSectionType = ELF::SHT_X86_64_UNWIND;
    else
      EHSectionFlags |= ELF::SHF_WRITE;
  }


  // ELF
  BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
                                  ELF::SHF_WRITE | ELF::SHF_ALLOC);

  TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
                                   ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);

  DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);

  ReadOnlySection =
      Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);

  TLSDataSection =
      Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
                         ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);

  TLSBSSSection = Ctx->getELFSection(
      ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);

  DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS,
                                      ELF::SHF_ALLOC | ELF::SHF_WRITE);

  DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS,
                                           ELF::SHF_ALLOC | ELF::SHF_WRITE);

  DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
                                        ELF::SHF_ALLOC | ELF::SHF_WRITE);

  DataRelROLocalSection = Ctx->getELFSection(
      ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE);

  MergeableConst4Section =
      Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
                         ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, "");

  MergeableConst8Section =
      Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
                         ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, "");

  MergeableConst16Section =
      Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
                         ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, "");

  StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS,
                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);

  StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS,
                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);

  // Exception Handling Sections.

  // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
  // it contains relocatable pointers.  In PIC mode, this is probably a big
  // runtime hit for C++ apps.  Either the contents of the LSDA need to be
  // adjusted or this should be a data section.
  LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
                                   ELF::SHF_ALLOC);

  COFFDebugSymbolsSection = nullptr;

  // Debug Info Sections.
  DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0,
                                          "section_abbrev");
  DwarfInfoSection =
      Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info");
  DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0);
  DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0);
  DwarfPubNamesSection =
      Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0);
  DwarfPubTypesSection =
      Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0);
  DwarfGnuPubNamesSection =
      Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0);
  DwarfGnuPubTypesSection =
      Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0);
  DwarfStrSection =
      Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS,
                         ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
  DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0);
  DwarfARangesSection =
      Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0);
  DwarfRangesSection =
      Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range");

  // DWARF5 Experimental Debug Info

  // Accelerator Tables
  DwarfAccelNamesSection =
      Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin");
  DwarfAccelObjCSection =
      Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin");
  DwarfAccelNamespaceSection = Ctx->getELFSection(
      ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin");
  DwarfAccelTypesSection =
      Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin");

  // Fission Sections
  DwarfInfoDWOSection =
      Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0);
  DwarfTypesDWOSection =
      Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0);
  DwarfAbbrevDWOSection =
      Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0);
  DwarfStrDWOSection =
      Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS,
                         ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
  DwarfLineDWOSection =
      Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0);
  DwarfLocDWOSection =
      Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc");
  DwarfStrOffDWOSection =
      Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0);
  DwarfAddrSection =
      Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec");

  StackMapSection =
      Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);

  FaultMapSection =
      Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
}

void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) {
  bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb;

  CommDirectiveSupportsAlignment = true;

  // COFF
  BSSSection = Ctx->getCOFFSection(
      ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
                  COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
      SectionKind::getBSS());
  TextSection = Ctx->getCOFFSection(
      ".text",
      (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) |
          COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getText());
  DataSection = Ctx->getCOFFSection(
      ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
                   COFF::IMAGE_SCN_MEM_WRITE,
      SectionKind::getDataRel());
  ReadOnlySection = Ctx->getCOFFSection(
      ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getReadOnly());

  if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) {
    StaticCtorSection =
        Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                            COFF::IMAGE_SCN_MEM_READ,
                            SectionKind::getReadOnly());
    StaticDtorSection =
        Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                            COFF::IMAGE_SCN_MEM_READ,
                            SectionKind::getReadOnly());
  } else {
    StaticCtorSection = Ctx->getCOFFSection(
        ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                      COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
        SectionKind::getDataRel());
    StaticDtorSection = Ctx->getCOFFSection(
        ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                      COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
        SectionKind::getDataRel());
  }

  // FIXME: We're emitting LSDA info into a readonly section on COFF, even
  // though it contains relocatable pointers.  In PIC mode, this is probably a
  // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
  // adjusted or this should be a data section.
  assert(T.isOSWindows() && "Windows is the only supported COFF target");
  if (T.getArch() == Triple::x86_64) {
    // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
    LSDASection = 0;
  } else {
    LSDASection = Ctx->getCOFFSection(".gcc_except_table",
                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                          COFF::IMAGE_SCN_MEM_READ,
                                      SectionKind::getReadOnly());
  }

  // Debug info.
  COFFDebugSymbolsSection =
      Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE |
                                          COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                          COFF::IMAGE_SCN_MEM_READ,
                          SectionKind::getMetadata());

  DwarfAbbrevSection = Ctx->getCOFFSection(
      ".debug_abbrev",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_abbrev");
  DwarfInfoSection = Ctx->getCOFFSection(
      ".debug_info",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_info");
  DwarfLineSection = Ctx->getCOFFSection(
      ".debug_line",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_line");

  DwarfFrameSection = Ctx->getCOFFSection(
      ".debug_frame",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfPubNamesSection = Ctx->getCOFFSection(
      ".debug_pubnames",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfPubTypesSection = Ctx->getCOFFSection(
      ".debug_pubtypes",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfGnuPubNamesSection = Ctx->getCOFFSection(
      ".debug_gnu_pubnames",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfGnuPubTypesSection = Ctx->getCOFFSection(
      ".debug_gnu_pubtypes",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfStrSection = Ctx->getCOFFSection(
      ".debug_str",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "info_string");
  DwarfLocSection = Ctx->getCOFFSection(
      ".debug_loc",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_debug_loc");
  DwarfARangesSection = Ctx->getCOFFSection(
      ".debug_aranges",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfRangesSection = Ctx->getCOFFSection(
      ".debug_ranges",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "debug_range");
  DwarfInfoDWOSection = Ctx->getCOFFSection(
      ".debug_info.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_info_dwo");
  DwarfTypesDWOSection = Ctx->getCOFFSection(
      ".debug_types.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_types_dwo");
  DwarfAbbrevDWOSection = Ctx->getCOFFSection(
      ".debug_abbrev.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "section_abbrev_dwo");
  DwarfStrDWOSection = Ctx->getCOFFSection(
      ".debug_str.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "skel_string");
  DwarfLineDWOSection = Ctx->getCOFFSection(
      ".debug_line.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfLocDWOSection = Ctx->getCOFFSection(
      ".debug_loc.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "skel_loc");
  DwarfStrOffDWOSection = Ctx->getCOFFSection(
      ".debug_str_offsets.dwo",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata());
  DwarfAddrSection = Ctx->getCOFFSection(
      ".debug_addr",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "addr_sec");
  DwarfAccelNamesSection = Ctx->getCOFFSection(
      ".apple_names",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "names_begin");
  DwarfAccelNamespaceSection = Ctx->getCOFFSection(
      ".apple_namespaces",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "namespac_begin");
  DwarfAccelTypesSection = Ctx->getCOFFSection(
      ".apple_types",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "types_begin");
  DwarfAccelObjCSection = Ctx->getCOFFSection(
      ".apple_objc",
      COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
          COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getMetadata(), "objc_begin");

  DrectveSection = Ctx->getCOFFSection(
      ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
      SectionKind::getMetadata());

  PDataSection = Ctx->getCOFFSection(
      ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getDataRel());

  XDataSection = Ctx->getCOFFSection(
      ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
      SectionKind::getDataRel());

  SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
                                      SectionKind::getMetadata());

  TLSDataSection = Ctx->getCOFFSection(
      ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
                   COFF::IMAGE_SCN_MEM_WRITE,
      SectionKind::getDataRel());
	  
  StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                            COFF::IMAGE_SCN_MEM_READ,
                                        SectionKind::getReadOnly());	
}

void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple,
                                            Reloc::Model relocm,
                                            CodeModel::Model cm,
                                            MCContext &ctx) {
  RelocM = relocm;
  CMModel = cm;
  Ctx = &ctx;

  // Common.
  CommDirectiveSupportsAlignment = true;
  SupportsWeakOmittedEHFrame = true;
  SupportsCompactUnwindWithoutEHFrame = false;

  PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
      dwarf::DW_EH_PE_absptr;

  CompactUnwindDwarfEHFrameOnly = 0;

  EHFrameSection = nullptr;             // Created on demand.
  CompactUnwindSection = nullptr;       // Used only by selected targets.
  DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
  DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
  DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
  DwarfAccelTypesSection = nullptr;     // Used only by selected targets.

  TT = TheTriple;

  Triple::ArchType Arch = TT.getArch();
  // FIXME: Checking for Arch here to filter out bogus triples such as
  // cellspu-apple-darwin. Perhaps we should fix in Triple?
  if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
       Arch == Triple::arm || Arch == Triple::thumb ||
       Arch == Triple::aarch64 ||
       Arch == Triple::ppc || Arch == Triple::ppc64 ||
       Arch == Triple::UnknownArch) &&
      TT.isOSBinFormatMachO()) {
    Env = IsMachO;
    initMachOMCObjectFileInfo(TT);
  } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 ||
              Arch == Triple::arm || Arch == Triple::thumb) &&
             (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) {
    Env = IsCOFF;
    initCOFFMCObjectFileInfo(TT);
  } else {
    Env = IsELF;
    initELFMCObjectFileInfo(TT);
  }
}

void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model RM,
                                            CodeModel::Model CM,
                                            MCContext &ctx) {
  InitMCObjectFileInfo(Triple(TT), RM, CM, ctx);
}

MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
  return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
                            0, utostr(Hash));
}

void MCObjectFileInfo::InitEHFrameSection() {
  if (Env == IsMachO)
    EHFrameSection =
      Ctx->getMachOSection("__TEXT", "__eh_frame",
                           MachO::S_COALESCED |
                           MachO::S_ATTR_NO_TOC |
                           MachO::S_ATTR_STRIP_STATIC_SYMS |
                           MachO::S_ATTR_LIVE_SUPPORT,
                           SectionKind::getReadOnly());
  else if (Env == IsELF)
    EHFrameSection =
        Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
  else
    EHFrameSection =
      Ctx->getCOFFSection(".eh_frame",
                          COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                          COFF::IMAGE_SCN_MEM_READ |
                          COFF::IMAGE_SCN_MEM_WRITE,
                          SectionKind::getDataRel());
}