TargetLoweringObjectFileImpl.cpp [plain text]
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Mangler.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSectionCOFF.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
using namespace dwarf;
MCSymbol *TargetLoweringObjectFileELF::getCFIPersonalitySymbol(
const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM,
MachineModuleInfo *MMI) const {
unsigned Encoding = getPersonalityEncoding();
if ((Encoding & 0x80) == dwarf::DW_EH_PE_indirect)
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 {
SmallString<64> NameData("DW.ref.");
NameData += Sym->getName();
MCSymbol *Label = 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,
0, Label->getName());
unsigned Size = TM.getDataLayout()->getPointerSize();
Streamer.SwitchSection(Sec);
Streamer.EmitValueToAlignment(TM.getDataLayout()->getPointerABIAlignment());
Streamer.EmitSymbolAttribute(Label, MCSA_ELF_TypeObject);
const MCExpr *E = MCConstantExpr::Create(Size, getContext());
Streamer.EmitELFSize(Label, E);
Streamer.EmitLabel(Label);
Streamer.EmitSymbolValue(Sym, Size);
}
const MCExpr *TargetLoweringObjectFileELF::getTTypeGlobalReference(
const GlobalValue *GV, unsigned Encoding, Mangler &Mang,
const TargetMachine &TM, MachineModuleInfo *MMI,
MCStreamer &Streamer) const {
if (Encoding & dwarf::DW_EH_PE_indirect) {
MachineModuleInfoELF &ELFMMI = MMI->getObjFileInfo<MachineModuleInfoELF>();
MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, ".DW.stub", Mang, TM);
MachineModuleInfoImpl::StubValueTy &StubSym = ELFMMI.getGVStubEntry(SSym);
if (!StubSym.getPointer()) {
MCSymbol *Sym = TM.getSymbol(GV, Mang);
StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
}
return TargetLoweringObjectFile::
getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()),
Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
}
return TargetLoweringObjectFile::
getTTypeGlobalReference(GV, Encoding, Mang, TM, MMI, Streamer);
}
static SectionKind
getELFKindForNamedSection(StringRef Name, SectionKind K) {
if (Name.empty() || Name[0] != '.') return K;
if (Name == ".bss" ||
Name.startswith(".bss.") ||
Name.startswith(".gnu.linkonce.b.") ||
Name.startswith(".llvm.linkonce.b.") ||
Name == ".sbss" ||
Name.startswith(".sbss.") ||
Name.startswith(".gnu.linkonce.sb.") ||
Name.startswith(".llvm.linkonce.sb."))
return SectionKind::getBSS();
if (Name == ".tdata" ||
Name.startswith(".tdata.") ||
Name.startswith(".gnu.linkonce.td.") ||
Name.startswith(".llvm.linkonce.td."))
return SectionKind::getThreadData();
if (Name == ".tbss" ||
Name.startswith(".tbss.") ||
Name.startswith(".gnu.linkonce.tb.") ||
Name.startswith(".llvm.linkonce.tb."))
return SectionKind::getThreadBSS();
return K;
}
static unsigned getELFSectionType(StringRef Name, SectionKind K) {
if (Name == ".init_array")
return ELF::SHT_INIT_ARRAY;
if (Name == ".fini_array")
return ELF::SHT_FINI_ARRAY;
if (Name == ".preinit_array")
return ELF::SHT_PREINIT_ARRAY;
if (K.isBSS() || K.isThreadBSS())
return ELF::SHT_NOBITS;
return ELF::SHT_PROGBITS;
}
static unsigned
getELFSectionFlags(SectionKind K, bool InCOMDAT) {
unsigned Flags = 0;
if (!K.isMetadata())
Flags |= ELF::SHF_ALLOC;
if (K.isText())
Flags |= ELF::SHF_EXECINSTR;
if (K.isWriteable())
Flags |= ELF::SHF_WRITE;
if (K.isThreadLocal())
Flags |= ELF::SHF_TLS;
if (!InCOMDAT && (K.isMergeableCString() || K.isMergeableConst()))
Flags |= ELF::SHF_MERGE;
if (K.isMergeableCString())
Flags |= ELF::SHF_STRINGS;
return Flags;
}
static const Comdat *getELFComdat(const GlobalValue *GV) {
const Comdat *C = GV->getComdat();
if (!C)
return nullptr;
if (C->getSelectionKind() != Comdat::Any)
report_fatal_error("ELF COMDATs only support SelectionKind::Any, '" +
C->getName() + "' cannot be lowered.");
return C;
}
const MCSection *TargetLoweringObjectFileELF::getExplicitSectionGlobal(
const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
const TargetMachine &TM) const {
StringRef SectionName = GV->getSection();
Kind = getELFKindForNamedSection(SectionName, Kind);
StringRef Group = "";
unsigned Flags = getELFSectionFlags(Kind, GV->hasComdat());
if (const Comdat *C = getELFComdat(GV)) {
Group = C->getName();
Flags |= ELF::SHF_GROUP;
}
return getContext().getELFSection(SectionName,
getELFSectionType(SectionName, Kind), Flags,
0, Group);
}
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.";
assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
return ".data.rel.ro.";
}
const MCSection *TargetLoweringObjectFileELF::
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const {
unsigned Flags = getELFSectionFlags(Kind, GV->hasComdat());
bool EmitUniquedSection = false;
if (!(Flags & ELF::SHF_MERGE) && !Kind.isCommon()) {
if (Kind.isText())
EmitUniquedSection = TM.getFunctionSections();
else
EmitUniquedSection = TM.getDataSections();
}
if (EmitUniquedSection || GV->hasComdat()) {
StringRef Prefix = getSectionPrefixForGlobal(Kind);
SmallString<128> Name(Prefix);
TM.getNameWithPrefix(Name, GV, Mang, true);
StringRef Group = "";
if (const Comdat *C = getELFComdat(GV)) {
Flags |= ELF::SHF_GROUP;
Group = C->getName();
}
return getContext().getELFSection(
Name.str(), getELFSectionType(Name.str(), Kind), Flags, 0, Group);
}
if (Kind.isText()) return TextSection;
if (Kind.isMergeableCString()) {
unsigned Align =
TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV));
unsigned EntrySize = 1;
if (Kind.isMergeable2ByteCString())
EntrySize = 2;
else if (Kind.isMergeable4ByteCString())
EntrySize = 4;
else
assert(Kind.isMergeable1ByteCString() && "unknown string width");
std::string SizeSpec = ".rodata.str" + utostr(EntrySize) + ".";
std::string Name = SizeSpec + utostr(Align);
return getContext().getELFSection(
Name, ELF::SHT_PROGBITS,
ELF::SHF_ALLOC | ELF::SHF_MERGE | ELF::SHF_STRINGS, EntrySize, "");
}
if (Kind.isMergeableConst()) {
if (Kind.isMergeableConst4() && MergeableConst4Section)
return MergeableConst4Section;
if (Kind.isMergeableConst8() && MergeableConst8Section)
return MergeableConst8Section;
if (Kind.isMergeableConst16() && MergeableConst16Section)
return MergeableConst16Section;
return ReadOnlySection; }
if (Kind.isReadOnly()) return ReadOnlySection;
if (Kind.isThreadData()) return TLSDataSection;
if (Kind.isThreadBSS()) return TLSBSSSection;
if (Kind.isBSS() || Kind.isCommon()) 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;
}
const MCSection *
TargetLoweringObjectFileELF::getSectionForConstant(SectionKind Kind,
const Constant *C) 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;
}
static const 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;
StringRef COMDAT = KeySym ? KeySym->getName() : "";
if (KeySym)
Flags |= ELF::SHF_GROUP;
if (UseInitArray) {
if (IsCtor) {
Type = ELF::SHT_INIT_ARRAY;
Name = ".init_array";
} else {
Type = ELF::SHT_FINI_ARRAY;
Name = ".fini_array";
}
if (Priority != 65535) {
Name += '.';
Name += utostr(Priority);
}
} else {
if (IsCtor)
Name = ".ctors";
else
Name = ".dtors";
if (Priority != 65535) {
Name += '.';
Name += utostr(65535 - Priority);
}
Type = ELF::SHT_PROGBITS;
}
return Ctx.getELFSection(Name, Type, Flags, 0, COMDAT);
}
const MCSection *TargetLoweringObjectFileELF::getStaticCtorSection(
unsigned Priority, const MCSymbol *KeySym) const {
return getStaticStructorSection(getContext(), UseInitArray, true, Priority,
KeySym);
}
const MCSection *TargetLoweringObjectFileELF::getStaticDtorSection(
unsigned Priority, const MCSymbol *KeySym) const {
return getStaticStructorSection(getContext(), UseInitArray, false, Priority,
KeySym);
}
void
TargetLoweringObjectFileELF::InitializeELF(bool UseInitArray_) {
UseInitArray = UseInitArray_;
if (!UseInitArray)
return;
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);
}
TargetLoweringObjectFileMachO::TargetLoweringObjectFileMachO()
: TargetLoweringObjectFile() {
SupportIndirectSymViaGOTPCRel = true;
}
StringRef TargetLoweringObjectFileMachO::
getDepLibFromLinkerOpt(StringRef LinkerOption) const {
const char *LibCmd = "-l";
if (LinkerOption.startswith(LibCmd))
return LinkerOption.substr(strlen(LibCmd));
return StringRef();
}
void TargetLoweringObjectFileMachO::
emitModuleFlags(MCStreamer &Streamer,
ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
Mangler &Mang, const TargetMachine &TM) const {
unsigned VersionVal = 0;
unsigned ImageInfoFlags = 0;
MDNode *LinkerOptions = nullptr;
StringRef SectionVal;
for (ArrayRef<Module::ModuleFlagEntry>::iterator
i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
const Module::ModuleFlagEntry &MFE = *i;
if (MFE.Behavior == Module::Require)
continue;
StringRef Key = MFE.Key->getString();
Metadata *Val = MFE.Val;
if (Key == "Objective-C Image Info Version") {
VersionVal = mdconst::extract<ConstantInt>(Val)->getZExtValue();
} else if (Key == "Objective-C Garbage Collection" ||
Key == "Objective-C GC Only" ||
Key == "Objective-C Is Simulated" ||
Key == "Objective-C Image Swift Version") {
ImageInfoFlags |= mdconst::extract<ConstantInt>(Val)->getZExtValue();
} else if (Key == "Objective-C Image Info Section") {
SectionVal = cast<MDString>(Val)->getString();
} else if (Key == "Linker Options") {
LinkerOptions = cast<MDNode>(Val);
}
}
if (LinkerOptions) {
for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
SmallVector<std::string, 4> StrOptions;
for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
StrOptions.push_back(MDOption->getString());
}
Streamer.EmitLinkerOptions(StrOptions);
}
}
if (SectionVal.empty()) return;
StringRef Segment, Section;
unsigned TAA = 0, StubSize = 0;
bool TAAParsed;
std::string ErrorCode =
MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
TAA, TAAParsed, StubSize);
if (!ErrorCode.empty())
report_fatal_error("Invalid section specifier '" + Section + "': " +
ErrorCode + ".");
const MCSectionMachO *S =
getContext().getMachOSection(Segment, Section, TAA, StubSize,
SectionKind::getDataNoRel());
Streamer.SwitchSection(S);
Streamer.EmitLabel(getContext().
GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
Streamer.EmitIntValue(VersionVal, 4);
Streamer.EmitIntValue(ImageInfoFlags, 4);
Streamer.AddBlankLine();
}
static void checkMachOComdat(const GlobalValue *GV) {
const Comdat *C = GV->getComdat();
if (!C)
return;
report_fatal_error("MachO doesn't support COMDATs, '" + C->getName() +
"' cannot be lowered.");
}
const MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal(
const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
const TargetMachine &TM) const {
StringRef Segment, Section;
unsigned TAA = 0, StubSize = 0;
bool TAAParsed;
checkMachOComdat(GV);
std::string ErrorCode =
MCSectionMachO::ParseSectionSpecifier(GV->getSection(), Segment, Section,
TAA, TAAParsed, StubSize);
if (!ErrorCode.empty()) {
report_fatal_error("Global variable '" + GV->getName() +
"' has an invalid section specifier '" +
GV->getSection() + "': " + ErrorCode + ".");
}
const MCSectionMachO *S =
getContext().getMachOSection(Segment, Section, TAA, StubSize, Kind);
if (!TAAParsed)
TAA = S->getTypeAndAttributes();
if (S->getTypeAndAttributes() != TAA || S->getStubSize() != StubSize) {
report_fatal_error("Global variable '" + GV->getName() +
"' section type or attributes does not match previous"
" section specifier");
}
return S;
}
const MCSection *TargetLoweringObjectFileMachO::
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const {
checkMachOComdat(GV);
if (Kind.isThreadBSS()) return TLSBSSSection;
if (Kind.isThreadData()) return TLSDataSection;
if (Kind.isText())
return GV->isWeakForLinker() ? TextCoalSection : TextSection;
if (GV->isWeakForLinker()) {
if (Kind.isReadOnly())
return ConstTextCoalSection;
return DataCoalSection;
}
if (Kind.isMergeable1ByteCString() &&
TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV)) < 32)
return CStringSection;
if (Kind.isMergeable2ByteCString() && !GV->hasExternalLinkage() &&
TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV)) < 32)
return UStringSection;
if (GV->hasPrivateLinkage() && Kind.isMergeableConst()) {
if (Kind.isMergeableConst4())
return FourByteConstantSection;
if (Kind.isMergeableConst8())
return EightByteConstantSection;
if (Kind.isMergeableConst16())
return SixteenByteConstantSection;
}
if (Kind.isReadOnly())
return ReadOnlySection;
if (Kind.isReadOnlyWithRel())
return ConstDataSection;
if (Kind.isBSSExtern())
return DataCommonSection;
if (Kind.isBSSLocal())
return DataBSSSection;
return DataSection;
}
const MCSection *
TargetLoweringObjectFileMachO::getSectionForConstant(SectionKind Kind,
const Constant *C) const {
if (Kind.isDataRel() || Kind.isReadOnlyWithRel())
return ConstDataSection;
if (Kind.isMergeableConst4())
return FourByteConstantSection;
if (Kind.isMergeableConst8())
return EightByteConstantSection;
if (Kind.isMergeableConst16())
return SixteenByteConstantSection;
return ReadOnlySection; }
const MCExpr *TargetLoweringObjectFileMachO::getTTypeGlobalReference(
const GlobalValue *GV, unsigned Encoding, Mangler &Mang,
const TargetMachine &TM, MachineModuleInfo *MMI,
MCStreamer &Streamer) const {
if (Encoding & DW_EH_PE_indirect) {
MachineModuleInfoMachO &MachOMMI =
MMI->getObjFileInfo<MachineModuleInfoMachO>();
MCSymbol *SSym =
getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr", Mang, TM);
MachineModuleInfoImpl::StubValueTy &StubSym =
GV->hasHiddenVisibility() ? MachOMMI.getHiddenGVStubEntry(SSym) :
MachOMMI.getGVStubEntry(SSym);
if (!StubSym.getPointer()) {
MCSymbol *Sym = TM.getSymbol(GV, Mang);
StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
}
return TargetLoweringObjectFile::
getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()),
Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
}
return TargetLoweringObjectFile::getTTypeGlobalReference(GV, Encoding, Mang,
TM, MMI, Streamer);
}
MCSymbol *TargetLoweringObjectFileMachO::getCFIPersonalitySymbol(
const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM,
MachineModuleInfo *MMI) const {
MachineModuleInfoMachO &MachOMMI =
MMI->getObjFileInfo<MachineModuleInfoMachO>();
MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr", Mang, TM);
MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(SSym);
if (!StubSym.getPointer()) {
MCSymbol *Sym = TM.getSymbol(GV, Mang);
StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
}
return SSym;
}
const MCExpr *TargetLoweringObjectFileMachO::getIndirectSymViaGOTPCRel(
const MCSymbol *Sym, const MCValue &MV, int64_t Offset,
MachineModuleInfo *MMI, MCStreamer &Streamer) const {
MachineModuleInfoMachO &MachOMMI =
MMI->getObjFileInfo<MachineModuleInfoMachO>();
MCContext &Ctx = getContext();
Offset = -MV.getConstant();
const MCSymbol *BaseSym = &MV.getSymB()->getSymbol();
SmallString<128> Name;
StringRef Suffix = "$non_lazy_ptr";
Name += DL->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<MCSymbol *>(Sym), true );
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);
}
static unsigned
getCOFFSectionFlags(SectionKind K) {
unsigned Flags = 0;
if (K.isMetadata())
Flags |=
COFF::IMAGE_SCN_MEM_DISCARDABLE;
else if (K.isText())
Flags |=
COFF::IMAGE_SCN_MEM_EXECUTE |
COFF::IMAGE_SCN_MEM_READ |
COFF::IMAGE_SCN_CNT_CODE;
else if (K.isBSS())
Flags |=
COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
COFF::IMAGE_SCN_MEM_READ |
COFF::IMAGE_SCN_MEM_WRITE;
else if (K.isThreadLocal())
Flags |=
COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
COFF::IMAGE_SCN_MEM_READ |
COFF::IMAGE_SCN_MEM_WRITE;
else if (K.isReadOnly() || K.isReadOnlyWithRel())
Flags |=
COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
COFF::IMAGE_SCN_MEM_READ;
else if (K.isWriteable())
Flags |=
COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
COFF::IMAGE_SCN_MEM_READ |
COFF::IMAGE_SCN_MEM_WRITE;
return Flags;
}
static const GlobalValue *getComdatGVForCOFF(const GlobalValue *GV) {
const Comdat *C = GV->getComdat();
assert(C && "expected GV to have a Comdat!");
StringRef ComdatGVName = C->getName();
const GlobalValue *ComdatGV = GV->getParent()->getNamedValue(ComdatGVName);
if (!ComdatGV)
report_fatal_error("Associative COMDAT symbol '" + ComdatGVName +
"' does not exist.");
if (ComdatGV->getComdat() != C)
report_fatal_error("Associative COMDAT symbol '" + ComdatGVName +
"' is not a key for its COMDAT.");
return ComdatGV;
}
static int getSelectionForCOFF(const GlobalValue *GV) {
if (const Comdat *C = GV->getComdat()) {
const GlobalValue *ComdatKey = getComdatGVForCOFF(GV);
if (const auto *GA = dyn_cast<GlobalAlias>(ComdatKey))
ComdatKey = GA->getBaseObject();
if (ComdatKey == GV) {
switch (C->getSelectionKind()) {
case Comdat::Any:
return COFF::IMAGE_COMDAT_SELECT_ANY;
case Comdat::ExactMatch:
return COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH;
case Comdat::Largest:
return COFF::IMAGE_COMDAT_SELECT_LARGEST;
case Comdat::NoDuplicates:
return COFF::IMAGE_COMDAT_SELECT_NODUPLICATES;
case Comdat::SameSize:
return COFF::IMAGE_COMDAT_SELECT_SAME_SIZE;
}
} else {
return COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE;
}
} else if (GV->isWeakForLinker()) {
return COFF::IMAGE_COMDAT_SELECT_ANY;
}
return 0;
}
const 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->hasComdat()) {
Selection = getSelectionForCOFF(GV);
const GlobalValue *ComdatGV;
if (Selection == COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE)
ComdatGV = getComdatGVForCOFF(GV);
else
ComdatGV = GV;
if (!ComdatGV->hasPrivateLinkage()) {
MCSymbol *Sym = TM.getSymbol(ComdatGV, Mang);
COMDATSymName = Sym->getName();
Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
} else {
Selection = 0;
}
}
return getContext().getCOFFSection(Name,
Characteristics,
Kind,
COMDATSymName,
Selection);
}
static const char *getCOFFSectionNameForUniqueGlobal(SectionKind Kind) {
if (Kind.isText())
return ".text";
if (Kind.isBSS())
return ".bss";
if (Kind.isThreadLocal())
return ".tls$";
if (Kind.isReadOnly() || Kind.isReadOnlyWithRel())
return ".rdata";
return ".data";
}
const MCSection *TargetLoweringObjectFileCOFF::
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const {
bool EmitUniquedSection;
if (Kind.isText())
EmitUniquedSection = TM.getFunctionSections();
else
EmitUniquedSection = TM.getDataSections();
if ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) {
const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
unsigned Characteristics = getCOFFSectionFlags(Kind);
Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
int Selection = getSelectionForCOFF(GV);
if (!Selection)
Selection = COFF::IMAGE_COMDAT_SELECT_NODUPLICATES;
const GlobalValue *ComdatGV;
if (GV->hasComdat())
ComdatGV = getComdatGVForCOFF(GV);
else
ComdatGV = GV;
if (!ComdatGV->hasPrivateLinkage()) {
MCSymbol *Sym = TM.getSymbol(ComdatGV, Mang);
StringRef COMDATSymName = Sym->getName();
return getContext().getCOFFSection(Name, Characteristics, Kind,
COMDATSymName, Selection);
}
}
if (Kind.isText())
return TextSection;
if (Kind.isThreadLocal())
return TLSDataSection;
if (Kind.isReadOnly() || Kind.isReadOnlyWithRel())
return ReadOnlySection;
if (Kind.isBSS() || Kind.isCommon())
return BSSSection;
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::
emitModuleFlags(MCStreamer &Streamer,
ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
Mangler &Mang, const TargetMachine &TM) const {
MDNode *LinkerOptions = nullptr;
for (ArrayRef<Module::ModuleFlagEntry>::iterator
i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
const Module::ModuleFlagEntry &MFE = *i;
StringRef Key = MFE.Key->getString();
Metadata *Val = MFE.Val;
if (Key == "Linker Options") {
LinkerOptions = cast<MDNode>(Val);
break;
}
}
if (!LinkerOptions)
return;
const MCSection *Sec = getDrectveSection();
Streamer.SwitchSection(Sec);
for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
StringRef Op = MDOption->getString();
std::string Escaped(" ");
if (!Op.startswith("\"") && (Op.find(" ") != StringRef::npos)) {
Escaped.push_back('\"');
Escaped.append(Op);
Escaped.push_back('\"');
} else {
Escaped.append(Op);
}
Streamer.EmitBytes(Escaped);
}
}
}
const MCSection *TargetLoweringObjectFileCOFF::getStaticCtorSection(
unsigned Priority, const MCSymbol *KeySym) const {
return getContext().getAssociativeCOFFSection(
cast<MCSectionCOFF>(StaticCtorSection), KeySym);
}
const MCSection *TargetLoweringObjectFileCOFF::getStaticDtorSection(
unsigned Priority, const MCSymbol *KeySym) const {
return getContext().getAssociativeCOFFSection(
cast<MCSectionCOFF>(StaticDtorSection), KeySym);
}