-/// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a
-/// pc-relative reference to the specified global variable from exception
-/// handling information. In addition to the symbol, this returns
-/// by-reference:
-///
-/// IsIndirect - True if the returned symbol is actually a stub that contains
-/// the address of the symbol, false if the symbol is the global itself.
-///
-/// IsPCRel - True if the symbol reference is already pc-relative, false if
-/// the caller needs to subtract off the address of the reference from the
-/// symbol.
-///
-const MCExpr *TargetLoweringObjectFile::
-getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
- MachineModuleInfo *MMI,
- bool &IsIndirect, bool &IsPCRel) const {
- // The generic implementation of this just returns a direct reference to the
- // symbol.
- IsIndirect = false;
- IsPCRel = false;
-
- SmallString<128> Name;
- Mang->getNameWithPrefix(Name, GV, false);
- return MCSymbolRefExpr::Create(Name.str(), getContext());
-}
-
-
-//===----------------------------------------------------------------------===//
-// ELF
-//===----------------------------------------------------------------------===//
-typedef StringMap<const MCSectionELF*> ELFUniqueMapTy;
-
-TargetLoweringObjectFileELF::~TargetLoweringObjectFileELF() {
- // If we have the section uniquing map, free it.
- delete (ELFUniqueMapTy*)UniquingMap;
-}
-
-const MCSection *TargetLoweringObjectFileELF::
-getELFSection(StringRef Section, unsigned Type, unsigned Flags,
- SectionKind Kind, bool IsExplicit) const {
- if (UniquingMap == 0)
- UniquingMap = new ELFUniqueMapTy();
- ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)UniquingMap;
-
- // Do the lookup, if we have a hit, return it.
- const MCSectionELF *&Entry = Map[Section];
- if (Entry) return Entry;
-
- return Entry = MCSectionELF::Create(Section, Type, Flags, Kind, IsExplicit,
- getContext());
-}
-
-void TargetLoweringObjectFileELF::Initialize(MCContext &Ctx,
- const TargetMachine &TM) {
- if (UniquingMap != 0)
- ((ELFUniqueMapTy*)UniquingMap)->clear();
- TargetLoweringObjectFile::Initialize(Ctx, TM);
-
- BSSSection =
- getELFSection(".bss", MCSectionELF::SHT_NOBITS,
- MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
- SectionKind::getBSS());
-
- TextSection =
- getELFSection(".text", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_EXECINSTR | MCSectionELF::SHF_ALLOC,
- SectionKind::getText());
-
- DataSection =
- getELFSection(".data", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
- SectionKind::getDataRel());
-
- ReadOnlySection =
- getELFSection(".rodata", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC,
- SectionKind::getReadOnly());
-
- TLSDataSection =
- getELFSection(".tdata", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
- MCSectionELF::SHF_WRITE, SectionKind::getThreadData());
-
- TLSBSSSection =
- getELFSection(".tbss", MCSectionELF::SHT_NOBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
- MCSectionELF::SHF_WRITE, SectionKind::getThreadBSS());
-
- DataRelSection =
- getELFSection(".data.rel", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getDataRel());
-
- DataRelLocalSection =
- getELFSection(".data.rel.local", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getDataRelLocal());
-
- DataRelROSection =
- getELFSection(".data.rel.ro", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getReadOnlyWithRel());
-
- DataRelROLocalSection =
- getELFSection(".data.rel.ro.local", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getReadOnlyWithRelLocal());
-
- MergeableConst4Section =
- getELFSection(".rodata.cst4", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
- SectionKind::getMergeableConst4());
-
- MergeableConst8Section =
- getELFSection(".rodata.cst8", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
- SectionKind::getMergeableConst8());
-
- MergeableConst16Section =
- getELFSection(".rodata.cst16", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
- SectionKind::getMergeableConst16());
-
- StaticCtorSection =
- getELFSection(".ctors", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getDataRel());
-
- StaticDtorSection =
- getELFSection(".dtors", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getDataRel());
-
- // 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 =
- getELFSection(".gcc_except_table", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC, SectionKind::getReadOnly());
- EHFrameSection =
- getELFSection(".eh_frame", MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
- SectionKind::getDataRel());
-
- // Debug Info Sections.
- DwarfAbbrevSection =
- getELFSection(".debug_abbrev", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfInfoSection =
- getELFSection(".debug_info", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfLineSection =
- getELFSection(".debug_line", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfFrameSection =
- getELFSection(".debug_frame", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfPubNamesSection =
- getELFSection(".debug_pubnames", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfPubTypesSection =
- getELFSection(".debug_pubtypes", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfStrSection =
- getELFSection(".debug_str", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfLocSection =
- getELFSection(".debug_loc", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfARangesSection =
- getELFSection(".debug_aranges", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfRangesSection =
- getELFSection(".debug_ranges", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
- DwarfMacroInfoSection =
- getELFSection(".debug_macinfo", MCSectionELF::SHT_PROGBITS, 0,
- SectionKind::getMetadata());
-}
-
-
-static SectionKind
-getELFKindForNamedSection(const char *Name, SectionKind K) {
- if (Name[0] != '.') return K;
-
- // Some lame default implementation based on some magic section names.
- if (strcmp(Name, ".bss") == 0 ||
- strncmp(Name, ".bss.", 5) == 0 ||
- strncmp(Name, ".gnu.linkonce.b.", 16) == 0 ||
- strncmp(Name, ".llvm.linkonce.b.", 17) == 0 ||
- strcmp(Name, ".sbss") == 0 ||
- strncmp(Name, ".sbss.", 6) == 0 ||
- strncmp(Name, ".gnu.linkonce.sb.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.sb.", 18) == 0)
- return SectionKind::getBSS();
-
- if (strcmp(Name, ".tdata") == 0 ||
- strncmp(Name, ".tdata.", 7) == 0 ||
- strncmp(Name, ".gnu.linkonce.td.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.td.", 18) == 0)
- return SectionKind::getThreadData();
-
- if (strcmp(Name, ".tbss") == 0 ||
- strncmp(Name, ".tbss.", 6) == 0 ||
- strncmp(Name, ".gnu.linkonce.tb.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.tb.", 18) == 0)
- return SectionKind::getThreadBSS();
-
- return K;
-}
-
-
-static unsigned getELFSectionType(StringRef Name, SectionKind K) {
-
- if (Name == ".init_array")
- return MCSectionELF::SHT_INIT_ARRAY;
-
- if (Name == ".fini_array")
- return MCSectionELF::SHT_FINI_ARRAY;
-
- if (Name == ".preinit_array")
- return MCSectionELF::SHT_PREINIT_ARRAY;
-
- if (K.isBSS() || K.isThreadBSS())
- return MCSectionELF::SHT_NOBITS;
-
- return MCSectionELF::SHT_PROGBITS;
-}
-
-
-static unsigned
-getELFSectionFlags(SectionKind K) {
- unsigned Flags = 0;
-
- if (!K.isMetadata())
- Flags |= MCSectionELF::SHF_ALLOC;
-
- if (K.isText())
- Flags |= MCSectionELF::SHF_EXECINSTR;
-
- if (K.isWriteable())
- Flags |= MCSectionELF::SHF_WRITE;
-
- if (K.isThreadLocal())
- Flags |= MCSectionELF::SHF_TLS;
-
- // K.isMergeableConst() is left out to honour PR4650
- if (K.isMergeableCString() || K.isMergeableConst4() ||
- K.isMergeableConst8() || K.isMergeableConst16())
- Flags |= MCSectionELF::SHF_MERGE;
-
- if (K.isMergeableCString())
- Flags |= MCSectionELF::SHF_STRINGS;
-
- return Flags;
-}
-
-
-const MCSection *TargetLoweringObjectFileELF::
-getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
- Mangler *Mang, const TargetMachine &TM) const {
- const char *SectionName = GV->getSection().c_str();
-
- // Infer section flags from the section name if we can.
- Kind = getELFKindForNamedSection(SectionName, Kind);
-
- return getELFSection(SectionName,
- getELFSectionType(SectionName, Kind),
- getELFSectionFlags(Kind), Kind, true);
-}
-
-static const char *getSectionPrefixForUniqueGlobal(SectionKind Kind) {
- if (Kind.isText()) return ".gnu.linkonce.t.";
- if (Kind.isReadOnly()) return ".gnu.linkonce.r.";
-
- if (Kind.isThreadData()) return ".gnu.linkonce.td.";
- if (Kind.isThreadBSS()) return ".gnu.linkonce.tb.";
-
- if (Kind.isBSS()) return ".gnu.linkonce.b.";
- if (Kind.isDataNoRel()) return ".gnu.linkonce.d.";
- if (Kind.isDataRelLocal()) return ".gnu.linkonce.d.rel.local.";
- if (Kind.isDataRel()) return ".gnu.linkonce.d.rel.";
- if (Kind.isReadOnlyWithRelLocal()) return ".gnu.linkonce.d.rel.ro.local.";
-
- assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
- return ".gnu.linkonce.d.rel.ro.";
-}
-
-const MCSection *TargetLoweringObjectFileELF::
-SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
- Mangler *Mang, const TargetMachine &TM) const {
-
- // If this global is linkonce/weak and the target handles this by emitting it
- // into a 'uniqued' section name, create and return the section now.
- if (GV->isWeakForLinker()) {
- const char *Prefix = getSectionPrefixForUniqueGlobal(Kind);
- SmallString<128> Name;
- Name.append(Prefix, Prefix+strlen(Prefix));
- // FIXME: This will fail for weak globals with no names, this also depends
- // on the mangling behavior of makeNameProper to mangle the section name
- // before construction. Instead, this should use getNameWithPrefix on the
- // global variable and the MCSection printing code should do the mangling.
- Mang->makeNameProper(Name, GV->getName());
-
- return getELFSection(Name.str(),
- getELFSectionType(Name.str(), Kind),
- getELFSectionFlags(Kind),
- Kind);
- }
-
- if (Kind.isText()) return TextSection;
-
- if (Kind.isMergeable1ByteCString() ||
- Kind.isMergeable2ByteCString() ||
- Kind.isMergeable4ByteCString()) {
-
- // We also need alignment here.
- // FIXME: this is getting the alignment of the character, not the
- // alignment of the global!
- unsigned Align =
- TM.getTargetData()->getPreferredAlignment(cast<GlobalVariable>(GV));
-
- const char *SizeSpec = ".rodata.str1.";
- if (Kind.isMergeable2ByteCString())
- SizeSpec = ".rodata.str2.";
- else if (Kind.isMergeable4ByteCString())
- SizeSpec = ".rodata.str4.";
- else
- assert(Kind.isMergeable1ByteCString() && "unknown string width");
-
-
- std::string Name = SizeSpec + utostr(Align);
- return getELFSection(Name.c_str(), MCSectionELF::SHT_PROGBITS,
- MCSectionELF::SHF_ALLOC |
- MCSectionELF::SHF_MERGE |
- MCSectionELF::SHF_STRINGS,
- Kind);
- }
-
- if (Kind.isMergeableConst()) {
- if (Kind.isMergeableConst4() && MergeableConst4Section)
- return MergeableConst4Section;
- if (Kind.isMergeableConst8() && MergeableConst8Section)
- return MergeableConst8Section;
- if (Kind.isMergeableConst16() && MergeableConst16Section)
- return MergeableConst16Section;
- return ReadOnlySection; // .const
- }
-
- if (Kind.isReadOnly()) return ReadOnlySection;
-
- if (Kind.isThreadData()) return TLSDataSection;
- if (Kind.isThreadBSS()) return TLSBSSSection;
-
- if (Kind.isBSS()) return BSSSection;
-
- if (Kind.isDataNoRel()) return DataSection;
- if (Kind.isDataRelLocal()) return DataRelLocalSection;
- if (Kind.isDataRel()) return DataRelSection;
- if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
-
- assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
- return DataRelROSection;
-}
-
-/// getSectionForConstant - Given a mergeable constant with the
-/// specified size and relocation information, return a section that it
-/// should be placed in.
-const MCSection *TargetLoweringObjectFileELF::
-getSectionForConstant(SectionKind Kind) const {
- if (Kind.isMergeableConst4() && MergeableConst4Section)
- return MergeableConst4Section;
- if (Kind.isMergeableConst8() && MergeableConst8Section)
- return MergeableConst8Section;
- if (Kind.isMergeableConst16() && MergeableConst16Section)
- return MergeableConst16Section;
- if (Kind.isReadOnly())
- return ReadOnlySection;
-
- if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
- assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
- return DataRelROSection;
-}
-
-//===----------------------------------------------------------------------===//
-// MachO
-//===----------------------------------------------------------------------===//
-
-typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;