X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FTargetLoweringObjectFileImpl.cpp;h=0f46571ce0e52cd2d4c1d0454130f11bf5e7d17d;hb=848219ca612e5488982f23c37c7459aeedff77e3;hp=55cc016cc983bdb2f4af80f13fd661683cf69022;hpb=dad20b2ae2544708d6a33abdb9bddd0a329f50e0;p=oota-llvm.git diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp index 55cc016cc98..0f46571ce0e 100644 --- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp +++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp @@ -30,7 +30,9 @@ #include "llvm/MC/MCSectionELF.h" #include "llvm/MC/MCSectionMachO.h" #include "llvm/MC/MCStreamer.h" -#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MCSymbolELF.h" +#include "llvm/MC/MCValue.h" +#include "llvm/Support/COFF.h" #include "llvm/Support/Dwarf.h" #include "llvm/Support/ELF.h" #include "llvm/Support/ErrorHandling.h" @@ -50,36 +52,32 @@ MCSymbol *TargetLoweringObjectFileELF::getCFIPersonalitySymbol( MachineModuleInfo *MMI) const { unsigned Encoding = getPersonalityEncoding(); if ((Encoding & 0x80) == dwarf::DW_EH_PE_indirect) - return getContext().GetOrCreateSymbol(StringRef("DW.ref.") + + return getContext().getOrCreateSymbol(StringRef("DW.ref.") + TM.getSymbol(GV, Mang)->getName()); if ((Encoding & 0x70) == dwarf::DW_EH_PE_absptr) return TM.getSymbol(GV, Mang); report_fatal_error("We do not support this DWARF encoding yet!"); } -void TargetLoweringObjectFileELF::emitPersonalityValue(MCStreamer &Streamer, - const TargetMachine &TM, - const MCSymbol *Sym) const { +void TargetLoweringObjectFileELF::emitPersonalityValue( + MCStreamer &Streamer, const DataLayout &DL, const MCSymbol *Sym) const { SmallString<64> NameData("DW.ref."); NameData += Sym->getName(); - MCSymbol *Label = getContext().GetOrCreateSymbol(NameData); + MCSymbolELF *Label = + cast(getContext().getOrCreateSymbol(NameData)); Streamer.EmitSymbolAttribute(Label, MCSA_Hidden); Streamer.EmitSymbolAttribute(Label, MCSA_Weak); StringRef Prefix = ".data."; NameData.insert(NameData.begin(), Prefix.begin(), Prefix.end()); unsigned Flags = ELF::SHF_ALLOC | ELF::SHF_WRITE | ELF::SHF_GROUP; - const MCSection *Sec = getContext().getELFSection(NameData, - ELF::SHT_PROGBITS, - Flags, - SectionKind::getDataRel(), - 0, Label->getName()); - unsigned Size = TM.getSubtargetImpl()->getDataLayout()->getPointerSize(); + MCSection *Sec = getContext().getELFSection(NameData, ELF::SHT_PROGBITS, + Flags, 0, Label->getName()); + unsigned Size = DL.getPointerSize(); Streamer.SwitchSection(Sec); - Streamer.EmitValueToAlignment( - TM.getSubtargetImpl()->getDataLayout()->getPointerABIAlignment()); + Streamer.EmitValueToAlignment(DL.getPointerABIAlignment()); Streamer.EmitSymbolAttribute(Label, MCSA_ELF_TypeObject); - const MCExpr *E = MCConstantExpr::Create(Size, getContext()); - Streamer.EmitELFSize(Label, E); + const MCExpr *E = MCConstantExpr::create(Size, getContext()); + Streamer.emitELFSize(Label, E); Streamer.EmitLabel(Label); Streamer.EmitSymbolValue(Sym, Size); @@ -104,7 +102,7 @@ const MCExpr *TargetLoweringObjectFileELF::getTTypeGlobalReference( } return TargetLoweringObjectFile:: - getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()), + getTTypeReference(MCSymbolRefExpr::create(SSym, getContext()), Encoding & ~dwarf::DW_EH_PE_indirect, Streamer); } @@ -166,9 +164,7 @@ static unsigned getELFSectionType(StringRef Name, SectionKind K) { return ELF::SHT_PROGBITS; } - -static unsigned -getELFSectionFlags(SectionKind K) { +static unsigned getELFSectionFlags(SectionKind K) { unsigned Flags = 0; if (!K.isMetadata()) @@ -183,9 +179,7 @@ getELFSectionFlags(SectionKind K) { if (K.isThreadLocal()) Flags |= ELF::SHF_TLS; - // K.isMergeableConst() is left out to honour PR4650 - if (K.isMergeableCString() || K.isMergeableConst4() || - K.isMergeableConst8() || K.isMergeableConst16()) + if (K.isMergeableCString() || K.isMergeableConst()) Flags |= ELF::SHF_MERGE; if (K.isMergeableCString()) @@ -206,7 +200,7 @@ static const Comdat *getELFComdat(const GlobalValue *GV) { return C; } -const MCSection *TargetLoweringObjectFileELF::getExplicitSectionGlobal( +MCSection *TargetLoweringObjectFileELF::getExplicitSectionGlobal( const GlobalValue *GV, SectionKind Kind, Mangler &Mang, const TargetMachine &TM) const { StringRef SectionName = GV->getSection(); @@ -222,128 +216,142 @@ const MCSection *TargetLoweringObjectFileELF::getExplicitSectionGlobal( } return getContext().getELFSection(SectionName, getELFSectionType(SectionName, Kind), Flags, - Kind, /*EntrySize=*/0, Group); + /*EntrySize=*/0, Group); } -/// getSectionPrefixForGlobal - Return the section prefix name used by options -/// FunctionsSections and DataSections. +/// Return the section prefix name used by options FunctionsSections and +/// DataSections. static StringRef getSectionPrefixForGlobal(SectionKind Kind) { - if (Kind.isText()) return ".text."; - if (Kind.isReadOnly()) return ".rodata."; - if (Kind.isBSS()) return ".bss."; - - if (Kind.isThreadData()) return ".tdata."; - if (Kind.isThreadBSS()) return ".tbss."; - - if (Kind.isDataNoRel()) return ".data."; - if (Kind.isDataRelLocal()) return ".data.rel.local."; - if (Kind.isDataRel()) return ".data.rel."; - if (Kind.isReadOnlyWithRelLocal()) return ".data.rel.ro.local."; - + if (Kind.isText()) + return ".text"; + if (Kind.isReadOnly()) + return ".rodata"; + if (Kind.isBSS()) + return ".bss"; + if (Kind.isThreadData()) + return ".tdata"; + if (Kind.isThreadBSS()) + return ".tbss"; + if (Kind.isDataNoRel()) + return ".data"; + if (Kind.isDataRelLocal()) + return ".data.rel.local"; + if (Kind.isDataRel()) + return ".data.rel"; + if (Kind.isReadOnlyWithRelLocal()) + return ".data.rel.ro.local"; assert(Kind.isReadOnlyWithRel() && "Unknown section kind"); - return ".data.rel.ro."; + return ".data.rel.ro"; } -const MCSection *TargetLoweringObjectFileELF:: -SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, - Mangler &Mang, const TargetMachine &TM) const { - // If we have -ffunction-section or -fdata-section then we should emit the - // global value to a uniqued section specifically for it. - bool EmitUniquedSection; - if (Kind.isText()) - EmitUniquedSection = TM.getFunctionSections(); - else - EmitUniquedSection = TM.getDataSections(); - - // 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() || EmitUniquedSection || GV->hasComdat()) && - !Kind.isCommon()) { - StringRef Prefix = getSectionPrefixForGlobal(Kind); - - SmallString<128> Name(Prefix); - TM.getNameWithPrefix(Name, GV, Mang, true); - - StringRef Group = ""; - unsigned Flags = getELFSectionFlags(Kind); - if (GV->isWeakForLinker() || GV->hasComdat()) { - if (const Comdat *C = getELFComdat(GV)) - Group = C->getName(); - else - Group = Name.substr(Prefix.size()); - Flags |= ELF::SHF_GROUP; +static MCSectionELF * +selectELFSectionForGlobal(MCContext &Ctx, const GlobalValue *GV, + SectionKind Kind, Mangler &Mang, + const TargetMachine &TM, bool EmitUniqueSection, + unsigned Flags, unsigned *NextUniqueID) { + unsigned EntrySize = 0; + if (Kind.isMergeableCString()) { + if (Kind.isMergeable2ByteCString()) { + EntrySize = 2; + } else if (Kind.isMergeable4ByteCString()) { + EntrySize = 4; + } else { + EntrySize = 1; + assert(Kind.isMergeable1ByteCString() && "unknown string width"); + } + } else if (Kind.isMergeableConst()) { + if (Kind.isMergeableConst4()) { + EntrySize = 4; + } else if (Kind.isMergeableConst8()) { + EntrySize = 8; + } else { + assert(Kind.isMergeableConst16() && "unknown data width"); + EntrySize = 16; } - - return getContext().getELFSection(Name.str(), - getELFSectionType(Name.str(), Kind), - Flags, Kind, 0, Group); } - if (Kind.isText()) return TextSection; - - if (Kind.isMergeable1ByteCString() || - Kind.isMergeable2ByteCString() || - Kind.isMergeable4ByteCString()) { + StringRef Group = ""; + if (const Comdat *C = getELFComdat(GV)) { + Flags |= ELF::SHF_GROUP; + Group = C->getName(); + } + bool UniqueSectionNames = TM.getUniqueSectionNames(); + SmallString<128> Name; + if (Kind.isMergeableCString()) { // We also need alignment here. // FIXME: this is getting the alignment of the character, not the // alignment of the global! - unsigned Align = - TM.getSubtargetImpl()->getDataLayout()->getPreferredAlignment( - cast(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 getContext().getELFSection(Name, ELF::SHT_PROGBITS, - ELF::SHF_ALLOC | - ELF::SHF_MERGE | - ELF::SHF_STRINGS, - Kind); + unsigned Align = GV->getParent()->getDataLayout().getPreferredAlignment( + cast(GV)); + + std::string SizeSpec = ".rodata.str" + utostr(EntrySize) + "."; + Name = SizeSpec + utostr(Align); + } else if (Kind.isMergeableConst()) { + Name = ".rodata.cst"; + Name += utostr(EntrySize); + } else { + Name = getSectionPrefixForGlobal(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 (EmitUniqueSection && UniqueSectionNames) { + Name.push_back('.'); + TM.getNameWithPrefix(Name, GV, Mang, true); } + unsigned UniqueID = ~0; + if (EmitUniqueSection && !UniqueSectionNames) { + UniqueID = *NextUniqueID; + (*NextUniqueID)++; + } + return Ctx.getELFSection(Name, getELFSectionType(Name, Kind), Flags, + EntrySize, Group, UniqueID); +} - if (Kind.isReadOnly()) return ReadOnlySection; +MCSection *TargetLoweringObjectFileELF::SelectSectionForGlobal( + const GlobalValue *GV, SectionKind Kind, Mangler &Mang, + const TargetMachine &TM) const { + unsigned Flags = getELFSectionFlags(Kind); - if (Kind.isThreadData()) return TLSDataSection; - if (Kind.isThreadBSS()) return TLSBSSSection; + // If we have -ffunction-section or -fdata-section then we should emit the + // global value to a uniqued section specifically for it. + bool EmitUniqueSection = false; + if (!(Flags & ELF::SHF_MERGE) && !Kind.isCommon()) { + if (Kind.isText()) + EmitUniqueSection = TM.getFunctionSections(); + else + EmitUniqueSection = TM.getDataSections(); + } + EmitUniqueSection |= GV->hasComdat(); - // Note: we claim that common symbols are put in BSSSection, but they are - // really emitted with the magic .comm directive, which creates a symbol table - // entry but not a section. - if (Kind.isBSS() || Kind.isCommon()) return BSSSection; + return selectELFSectionForGlobal(getContext(), GV, Kind, Mang, TM, + EmitUniqueSection, Flags, &NextUniqueID); +} - if (Kind.isDataNoRel()) return DataSection; - if (Kind.isDataRelLocal()) return DataRelLocalSection; - if (Kind.isDataRel()) return DataRelSection; - if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection; +MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable( + const Function &F, Mangler &Mang, const TargetMachine &TM) const { + // If the function can be removed, produce a unique section so that + // the table doesn't prevent the removal. + const Comdat *C = F.getComdat(); + bool EmitUniqueSection = TM.getFunctionSections() || C; + if (!EmitUniqueSection) + return ReadOnlySection; - assert(Kind.isReadOnlyWithRel() && "Unknown section kind"); - return DataRelROSection; + return selectELFSectionForGlobal(getContext(), &F, SectionKind::getReadOnly(), + Mang, TM, EmitUniqueSection, ELF::SHF_ALLOC, + &NextUniqueID); +} + +bool TargetLoweringObjectFileELF::shouldPutJumpTableInFunctionSection( + bool UsesLabelDifference, const Function &F) const { + // We can always create relative relocations, so use another section + // that can be marked non-executable. + return false; } -/// 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 Constant *C) const { +/// Given a mergeable constant with the specified size and relocation +/// information, return a section that it should be placed in. +MCSection *TargetLoweringObjectFileELF::getSectionForConstant( + const DataLayout &DL, SectionKind Kind, const Constant *C) const { if (Kind.isMergeableConst4() && MergeableConst4Section) return MergeableConst4Section; if (Kind.isMergeableConst8() && MergeableConst8Section) @@ -358,15 +366,12 @@ TargetLoweringObjectFileELF::getSectionForConstant(SectionKind Kind, return DataRelROSection; } -static const MCSectionELF *getStaticStructorSection(MCContext &Ctx, - bool UseInitArray, - bool IsCtor, - unsigned Priority, - const MCSymbol *KeySym) { +static MCSectionELF *getStaticStructorSection(MCContext &Ctx, bool UseInitArray, + bool IsCtor, unsigned Priority, + const MCSymbol *KeySym) { std::string Name; unsigned Type; unsigned Flags = ELF::SHF_ALLOC | ELF::SHF_WRITE; - SectionKind Kind = SectionKind::getDataRel(); StringRef COMDAT = KeySym ? KeySym->getName() : ""; if (KeySym) @@ -398,16 +403,16 @@ static const MCSectionELF *getStaticStructorSection(MCContext &Ctx, Type = ELF::SHT_PROGBITS; } - return Ctx.getELFSection(Name, Type, Flags, Kind, 0, COMDAT); + return Ctx.getELFSection(Name, Type, Flags, 0, COMDAT); } -const MCSection *TargetLoweringObjectFileELF::getStaticCtorSection( +MCSection *TargetLoweringObjectFileELF::getStaticCtorSection( unsigned Priority, const MCSymbol *KeySym) const { return getStaticStructorSection(getContext(), UseInitArray, true, Priority, KeySym); } -const MCSection *TargetLoweringObjectFileELF::getStaticDtorSection( +MCSection *TargetLoweringObjectFileELF::getStaticDtorSection( unsigned Priority, const MCSymbol *KeySym) const { return getStaticStructorSection(getContext(), UseInitArray, false, Priority, KeySym); @@ -419,30 +424,19 @@ TargetLoweringObjectFileELF::InitializeELF(bool UseInitArray_) { if (!UseInitArray) return; - StaticCtorSection = - getContext().getELFSection(".init_array", ELF::SHT_INIT_ARRAY, - ELF::SHF_WRITE | - ELF::SHF_ALLOC, - SectionKind::getDataRel()); - StaticDtorSection = - getContext().getELFSection(".fini_array", ELF::SHT_FINI_ARRAY, - ELF::SHF_WRITE | - ELF::SHF_ALLOC, - SectionKind::getDataRel()); + StaticCtorSection = getContext().getELFSection( + ".init_array", ELF::SHT_INIT_ARRAY, ELF::SHF_WRITE | ELF::SHF_ALLOC); + StaticDtorSection = getContext().getELFSection( + ".fini_array", ELF::SHT_FINI_ARRAY, ELF::SHF_WRITE | ELF::SHF_ALLOC); } //===----------------------------------------------------------------------===// // MachO //===----------------------------------------------------------------------===// -/// getDepLibFromLinkerOpt - Extract the dependent library name from a linker -/// option string. Returns StringRef() if the option does not specify a library. -StringRef TargetLoweringObjectFileMachO:: -getDepLibFromLinkerOpt(StringRef LinkerOption) const { - const char *LibCmd = "-l"; - if (LinkerOption.startswith(LibCmd)) - return LinkerOption.substr(strlen(LibCmd)); - return StringRef(); +TargetLoweringObjectFileMachO::TargetLoweringObjectFileMachO() + : TargetLoweringObjectFile() { + SupportIndirectSymViaGOTPCRel = true; } /// emitModuleFlags - Perform code emission for module flags. @@ -511,12 +505,11 @@ emitModuleFlags(MCStreamer &Streamer, ErrorCode + "."); // Get the section. - const MCSectionMachO *S = - getContext().getMachOSection(Segment, Section, TAA, StubSize, - SectionKind::getDataNoRel()); + MCSectionMachO *S = getContext().getMachOSection( + Segment, Section, TAA, StubSize, SectionKind::getDataNoRel()); Streamer.SwitchSection(S); Streamer.EmitLabel(getContext(). - GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO"))); + getOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO"))); Streamer.EmitIntValue(VersionVal, 4); Streamer.EmitIntValue(ImageInfoFlags, 4); Streamer.AddBlankLine(); @@ -531,7 +524,7 @@ static void checkMachOComdat(const GlobalValue *GV) { "' cannot be lowered."); } -const MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal( +MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal( const GlobalValue *GV, SectionKind Kind, Mangler &Mang, const TargetMachine &TM) const { // Parse the section specifier and create it if valid. @@ -552,8 +545,8 @@ const MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal( } // Get the section. - const MCSectionMachO *S = - getContext().getMachOSection(Segment, Section, TAA, StubSize, Kind); + MCSectionMachO *S = + getContext().getMachOSection(Segment, Section, TAA, StubSize, Kind); // If TAA wasn't set by ParseSectionSpecifier() above, // use the value returned by getMachOSection() as a default. @@ -573,63 +566,9 @@ const MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal( return S; } -bool TargetLoweringObjectFileMachO::isSectionAtomizableBySymbols( - const MCSection &Section) const { - const MCSectionMachO &SMO = static_cast(Section); - - // Sections holding 1 byte strings are atomized based on the data - // they contain. - // Sections holding 2 byte strings require symbols in order to be - // atomized. - // There is no dedicated section for 4 byte strings. - if (SMO.getKind().isMergeable1ByteCString()) - return false; - - if (SMO.getSegmentName() == "__TEXT" && - SMO.getSectionName() == "__objc_classname" && - SMO.getType() == MachO::S_CSTRING_LITERALS) - return false; - - if (SMO.getSegmentName() == "__TEXT" && - SMO.getSectionName() == "__objc_methname" && - SMO.getType() == MachO::S_CSTRING_LITERALS) - return false; - - if (SMO.getSegmentName() == "__TEXT" && - SMO.getSectionName() == "__objc_methtype" && - SMO.getType() == MachO::S_CSTRING_LITERALS) - return false; - - if (SMO.getSegmentName() == "__DATA" && - SMO.getSectionName() == "__cfstring") - return false; - - // no_dead_strip sections are not atomized in practice. - if (SMO.hasAttribute(MachO::S_ATTR_NO_DEAD_STRIP)) - return false; - - switch (SMO.getType()) { - default: - return true; - - // These sections are atomized at the element boundaries without using - // symbols. - case MachO::S_4BYTE_LITERALS: - case MachO::S_8BYTE_LITERALS: - case MachO::S_16BYTE_LITERALS: - case MachO::S_LITERAL_POINTERS: - case MachO::S_NON_LAZY_SYMBOL_POINTERS: - case MachO::S_LAZY_SYMBOL_POINTERS: - case MachO::S_MOD_INIT_FUNC_POINTERS: - case MachO::S_MOD_TERM_FUNC_POINTERS: - case MachO::S_INTERPOSING: - return false; - } -} - -const MCSection *TargetLoweringObjectFileMachO:: -SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, - Mangler &Mang, const TargetMachine &TM) const { +MCSection *TargetLoweringObjectFileMachO::SelectSectionForGlobal( + const GlobalValue *GV, SectionKind Kind, Mangler &Mang, + const TargetMachine &TM) const { checkMachOComdat(GV); // Handle thread local data. @@ -649,7 +588,7 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, // FIXME: Alignment check should be handled by section classifier. if (Kind.isMergeable1ByteCString() && - TM.getSubtargetImpl()->getDataLayout()->getPreferredAlignment( + GV->getParent()->getDataLayout().getPreferredAlignment( cast(GV)) < 32) return CStringSection; @@ -657,7 +596,7 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, // externally visible label, this runs into issues with certain linker // versions. if (Kind.isMergeable2ByteCString() && !GV->hasExternalLinkage() && - TM.getSubtargetImpl()->getDataLayout()->getPreferredAlignment( + GV->getParent()->getDataLayout().getPreferredAlignment( cast(GV)) < 32) return UStringSection; @@ -696,9 +635,8 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, return DataSection; } -const MCSection * -TargetLoweringObjectFileMachO::getSectionForConstant(SectionKind Kind, - const Constant *C) const { +MCSection *TargetLoweringObjectFileMachO::getSectionForConstant( + const DataLayout &DL, SectionKind Kind, const Constant *C) const { // If this constant requires a relocation, we have to put it in the data // segment, not in the text segment. if (Kind.isDataRel() || Kind.isReadOnlyWithRel()) @@ -737,7 +675,7 @@ const MCExpr *TargetLoweringObjectFileMachO::getTTypeGlobalReference( } return TargetLoweringObjectFile:: - getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()), + getTTypeReference(MCSymbolRefExpr::create(SSym, getContext()), Encoding & ~dwarf::DW_EH_PE_indirect, Streamer); } @@ -765,6 +703,66 @@ MCSymbol *TargetLoweringObjectFileMachO::getCFIPersonalitySymbol( return SSym; } +const MCExpr *TargetLoweringObjectFileMachO::getIndirectSymViaGOTPCRel( + const MCSymbol *Sym, const MCValue &MV, int64_t Offset, + MachineModuleInfo *MMI, MCStreamer &Streamer) const { + // Although MachO 32-bit targets do not explicitly have a GOTPCREL relocation + // as 64-bit do, we replace the GOT equivalent by accessing the final symbol + // through a non_lazy_ptr stub instead. One advantage is that it allows the + // computation of deltas to final external symbols. Example: + // + // _extgotequiv: + // .long _extfoo + // + // _delta: + // .long _extgotequiv-_delta + // + // is transformed to: + // + // _delta: + // .long L_extfoo$non_lazy_ptr-(_delta+0) + // + // .section __IMPORT,__pointers,non_lazy_symbol_pointers + // L_extfoo$non_lazy_ptr: + // .indirect_symbol _extfoo + // .long 0 + // + MachineModuleInfoMachO &MachOMMI = + MMI->getObjFileInfo(); + MCContext &Ctx = getContext(); + + // The offset must consider the original displacement from the base symbol + // since 32-bit targets don't have a GOTPCREL to fold the PC displacement. + Offset = -MV.getConstant(); + const MCSymbol *BaseSym = &MV.getSymB()->getSymbol(); + + // Access the final symbol via sym$non_lazy_ptr and generate the appropriated + // non_lazy_ptr stubs. + SmallString<128> Name; + StringRef Suffix = "$non_lazy_ptr"; + Name += MMI->getModule()->getDataLayout().getPrivateGlobalPrefix(); + Name += Sym->getName(); + Name += Suffix; + MCSymbol *Stub = Ctx.getOrCreateSymbol(Name); + + MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(Stub); + if (!StubSym.getPointer()) + StubSym = MachineModuleInfoImpl:: + StubValueTy(const_cast(Sym), true /* access indirectly */); + + const MCExpr *BSymExpr = + MCSymbolRefExpr::create(BaseSym, MCSymbolRefExpr::VK_None, Ctx); + const MCExpr *LHS = + MCSymbolRefExpr::create(Stub, MCSymbolRefExpr::VK_None, Ctx); + + if (!Offset) + return MCBinaryExpr::createSub(LHS, BSymExpr, Ctx); + + const MCExpr *RHS = + MCBinaryExpr::createAdd(BSymExpr, MCConstantExpr::create(Offset, Ctx), Ctx); + return MCBinaryExpr::createSub(LHS, RHS, Ctx); +} + //===----------------------------------------------------------------------===// // COFF //===----------------------------------------------------------------------===// @@ -842,20 +840,18 @@ static int getSelectionForCOFF(const GlobalValue *GV) { } else { return COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE; } - } else if (GV->isWeakForLinker()) { - return COFF::IMAGE_COMDAT_SELECT_ANY; } return 0; } -const MCSection *TargetLoweringObjectFileCOFF::getExplicitSectionGlobal( +MCSection *TargetLoweringObjectFileCOFF::getExplicitSectionGlobal( const GlobalValue *GV, SectionKind Kind, Mangler &Mang, const TargetMachine &TM) const { int Selection = 0; unsigned Characteristics = getCOFFSectionFlags(Kind); StringRef Name = GV->getSection(); StringRef COMDATSymName = ""; - if ((GV->isWeakForLinker() || GV->hasComdat()) && !Kind.isCommon()) { + if (GV->hasComdat()) { Selection = getSelectionForCOFF(GV); const GlobalValue *ComdatGV; if (Selection == COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE) @@ -890,10 +886,9 @@ static const char *getCOFFSectionNameForUniqueGlobal(SectionKind Kind) { return ".data"; } - -const MCSection *TargetLoweringObjectFileCOFF:: -SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, - Mangler &Mang, const TargetMachine &TM) const { +MCSection *TargetLoweringObjectFileCOFF::SelectSectionForGlobal( + const GlobalValue *GV, SectionKind Kind, Mangler &Mang, + const TargetMachine &TM) const { // If we have -ffunction-sections then we should emit the global value to a // uniqued section specifically for it. bool EmitUniquedSection; @@ -902,12 +897,7 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, else EmitUniquedSection = TM.getDataSections(); - // 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. - // Section names depend on the name of the symbol which is not feasible if the - // symbol has private linkage. - if ((GV->isWeakForLinker() || EmitUniquedSection || GV->hasComdat()) && - !Kind.isCommon()) { + if ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) { const char *Name = getCOFFSectionNameForUniqueGlobal(Kind); unsigned Characteristics = getCOFFSectionFlags(Kind); @@ -926,6 +916,11 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, StringRef COMDATSymName = Sym->getName(); return getContext().getCOFFSection(Name, Characteristics, Kind, COMDATSymName, Selection); + } else { + SmallString<256> TmpData; + getNameWithPrefix(TmpData, GV, /*CannotUsePrivateLabel=*/true, Mang, TM); + return getContext().getCOFFSection(Name, Characteristics, Kind, TmpData, + Selection); } } @@ -947,12 +942,40 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, return DataSection; } -StringRef TargetLoweringObjectFileCOFF:: -getDepLibFromLinkerOpt(StringRef LinkerOption) const { - const char *LibCmd = "/DEFAULTLIB:"; - if (LinkerOption.startswith(LibCmd)) - return LinkerOption.substr(strlen(LibCmd)); - return StringRef(); +void TargetLoweringObjectFileCOFF::getNameWithPrefix( + SmallVectorImpl &OutName, const GlobalValue *GV, + bool CannotUsePrivateLabel, Mangler &Mang, const TargetMachine &TM) const { + if (GV->hasPrivateLinkage() && + ((isa(GV) && TM.getFunctionSections()) || + (isa(GV) && TM.getDataSections()))) + CannotUsePrivateLabel = true; + + Mang.getNameWithPrefix(OutName, GV, CannotUsePrivateLabel); +} + +MCSection *TargetLoweringObjectFileCOFF::getSectionForJumpTable( + const Function &F, Mangler &Mang, const TargetMachine &TM) const { + // If the function can be removed, produce a unique section so that + // the table doesn't prevent the removal. + const Comdat *C = F.getComdat(); + bool EmitUniqueSection = TM.getFunctionSections() || C; + if (!EmitUniqueSection) + return ReadOnlySection; + + // FIXME: we should produce a symbol for F instead. + if (F.hasPrivateLinkage()) + return ReadOnlySection; + + MCSymbol *Sym = TM.getSymbol(&F, Mang); + StringRef COMDATSymName = Sym->getName(); + + SectionKind Kind = SectionKind::getReadOnly(); + const char *Name = getCOFFSectionNameForUniqueGlobal(Kind); + unsigned Characteristics = getCOFFSectionFlags(Kind); + Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT; + + return getContext().getCOFFSection(Name, Characteristics, Kind, COMDATSymName, + COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE); } void TargetLoweringObjectFileCOFF:: @@ -977,39 +1000,61 @@ emitModuleFlags(MCStreamer &Streamer, // Emit the linker options to the linker .drectve section. According to the // spec, this section is a space-separated string containing flags for linker. - const MCSection *Sec = getDrectveSection(); + MCSection *Sec = getDrectveSection(); Streamer.SwitchSection(Sec); for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) { MDNode *MDOptions = cast(LinkerOptions->getOperand(i)); for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) { MDString *MDOption = cast(MDOptions->getOperand(ii)); - StringRef Op = MDOption->getString(); // Lead with a space for consistency with our dllexport implementation. - std::string Escaped(" "); - if (Op.find(" ") != StringRef::npos) { - // The PE-COFF spec says args with spaces must be quoted. It doesn't say - // how to escape quotes, but it probably uses this algorithm: - // http://msdn.microsoft.com/en-us/library/17w5ykft(v=vs.85).aspx - // FIXME: Reuse escaping code from Support/Windows/Program.inc - Escaped.push_back('\"'); - Escaped.append(Op); - Escaped.push_back('\"'); - } else { - Escaped.append(Op); - } - Streamer.EmitBytes(Escaped); + std::string Directive(" "); + Directive.append(MDOption->getString()); + Streamer.EmitBytes(Directive); } } } -const MCSection *TargetLoweringObjectFileCOFF::getStaticCtorSection( +MCSection *TargetLoweringObjectFileCOFF::getStaticCtorSection( unsigned Priority, const MCSymbol *KeySym) const { return getContext().getAssociativeCOFFSection( cast(StaticCtorSection), KeySym); } -const MCSection *TargetLoweringObjectFileCOFF::getStaticDtorSection( +MCSection *TargetLoweringObjectFileCOFF::getStaticDtorSection( unsigned Priority, const MCSymbol *KeySym) const { return getContext().getAssociativeCOFFSection( cast(StaticDtorSection), KeySym); } + +void TargetLoweringObjectFileCOFF::emitLinkerFlagsForGlobal( + raw_ostream &OS, const GlobalValue *GV, const Mangler &Mang) const { + if (!GV->hasDLLExportStorageClass() || GV->isDeclaration()) + return; + + const Triple &TT = getTargetTriple(); + + if (TT.isKnownWindowsMSVCEnvironment()) + OS << " /EXPORT:"; + else + OS << " -export:"; + + if (TT.isWindowsGNUEnvironment() || TT.isWindowsCygwinEnvironment()) { + std::string Flag; + raw_string_ostream FlagOS(Flag); + Mang.getNameWithPrefix(FlagOS, GV, false); + FlagOS.flush(); + if (Flag[0] == GV->getParent()->getDataLayout().getGlobalPrefix()) + OS << Flag.substr(1); + else + OS << Flag; + } else { + Mang.getNameWithPrefix(OS, GV, false); + } + + if (!GV->getValueType()->isFunctionTy()) { + if (TT.isKnownWindowsMSVCEnvironment()) + OS << ",DATA"; + else + OS << ",data"; + } +}