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diff --git a/contrib/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/contrib/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
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+++ b/contrib/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
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+//===- llvm/CodeGen/TargetLoweringObjectFileImpl.cpp - Object File Info ---===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements classes used to handle lowerings specific to common
+// object file formats.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineModuleInfoImpls.h"
+#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
+#include "llvm/IR/Comdat.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalObject.h"
+#include "llvm/IR/GlobalValue.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/MC/MCAsmInfo.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/MCSectionWasm.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSymbolELF.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/MC/SectionKind.h"
+#include "llvm/ProfileData/InstrProf.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/CodeGen.h"
+#include "llvm/Support/COFF.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MachO.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetMachine.h"
+#include <cassert>
+#include <string>
+
+using namespace llvm;
+using namespace dwarf;
+
+//===----------------------------------------------------------------------===//
+// ELF
+//===----------------------------------------------------------------------===//
+
+MCSymbol *TargetLoweringObjectFileELF::getCFIPersonalitySymbol(
+ const GlobalValue *GV, const TargetMachine &TM,
+ MachineModuleInfo *MMI) const {
+ unsigned Encoding = getPersonalityEncoding();
+ if ((Encoding & 0x80) == DW_EH_PE_indirect)
+ return getContext().getOrCreateSymbol(StringRef("DW.ref.") +
+ TM.getSymbol(GV)->getName());
+ if ((Encoding & 0x70) == DW_EH_PE_absptr)
+ return TM.getSymbol(GV);
+ report_fatal_error("We do not support this DWARF encoding yet!");
+}
+
+void TargetLoweringObjectFileELF::emitPersonalityValue(
+ MCStreamer &Streamer, const DataLayout &DL, const MCSymbol *Sym) const {
+ SmallString<64> NameData("DW.ref.");
+ NameData += Sym->getName();
+ MCSymbolELF *Label =
+ cast<MCSymbolELF>(getContext().getOrCreateSymbol(NameData));
+ Streamer.EmitSymbolAttribute(Label, MCSA_Hidden);
+ Streamer.EmitSymbolAttribute(Label, MCSA_Weak);
+ unsigned Flags = ELF::SHF_ALLOC | ELF::SHF_WRITE | ELF::SHF_GROUP;
+ MCSection *Sec = getContext().getELFNamedSection(".data", Label->getName(),
+ ELF::SHT_PROGBITS, Flags, 0);
+ unsigned Size = DL.getPointerSize();
+ Streamer.SwitchSection(Sec);
+ Streamer.EmitValueToAlignment(DL.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, const TargetMachine &TM,
+ MachineModuleInfo *MMI, MCStreamer &Streamer) const {
+ if (Encoding & DW_EH_PE_indirect) {
+ MachineModuleInfoELF &ELFMMI = MMI->getObjFileInfo<MachineModuleInfoELF>();
+
+ MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, ".DW.stub", TM);
+
+ // Add information about the stub reference to ELFMMI so that the stub
+ // gets emitted by the asmprinter.
+ MachineModuleInfoImpl::StubValueTy &StubSym = ELFMMI.getGVStubEntry(SSym);
+ if (!StubSym.getPointer()) {
+ MCSymbol *Sym = TM.getSymbol(GV);
+ StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
+ }
+
+ return TargetLoweringObjectFile::
+ getTTypeReference(MCSymbolRefExpr::create(SSym, getContext()),
+ Encoding & ~DW_EH_PE_indirect, Streamer);
+ }
+
+ return TargetLoweringObjectFile::getTTypeGlobalReference(GV, Encoding, TM,
+ MMI, Streamer);
+}
+
+static SectionKind
+getELFKindForNamedSection(StringRef Name, SectionKind K) {
+ // N.B.: The defaults used in here are no the same ones used in MC.
+ // We follow gcc, MC follows gas. For example, given ".section .eh_frame",
+ // both gas and MC will produce a section with no flags. Given
+ // section(".eh_frame") gcc will produce:
+ //
+ // .section .eh_frame,"a",@progbits
+
+ if (Name == getInstrProfSectionName(IPSK_covmap, Triple::ELF,
+ /*AddSegmentInfo=*/false))
+ return SectionKind::getMetadata();
+
+ if (Name.empty() || Name[0] != '.') return K;
+
+ // Some lame default implementation based on some magic section names.
+ 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) {
+ // Use SHT_NOTE for section whose name starts with ".note" to allow
+ // emitting ELF notes from C variable declaration.
+ // See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77609
+ if (Name.startswith(".note"))
+ return ELF::SHT_NOTE;
+
+ 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) {
+ unsigned Flags = 0;
+
+ if (!K.isMetadata())
+ Flags |= ELF::SHF_ALLOC;
+
+ if (K.isText())
+ Flags |= ELF::SHF_EXECINSTR;
+
+ if (K.isExecuteOnly())
+ Flags |= ELF::SHF_ARM_PURECODE;
+
+ if (K.isWriteable())
+ Flags |= ELF::SHF_WRITE;
+
+ if (K.isThreadLocal())
+ Flags |= ELF::SHF_TLS;
+
+ if (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;
+}
+
+static const MCSymbolELF *getAssociatedSymbol(const GlobalObject *GO,
+ const TargetMachine &TM) {
+ MDNode *MD = GO->getMetadata(LLVMContext::MD_associated);
+ if (!MD)
+ return nullptr;
+
+ const MDOperand &Op = MD->getOperand(0);
+ if (!Op.get())
+ return nullptr;
+
+ auto *VM = dyn_cast<ValueAsMetadata>(Op);
+ if (!VM)
+ report_fatal_error("MD_associated operand is not ValueAsMetadata");
+
+ GlobalObject *OtherGO = dyn_cast<GlobalObject>(VM->getValue());
+ return OtherGO ? dyn_cast<MCSymbolELF>(TM.getSymbol(OtherGO)) : nullptr;
+}
+
+MCSection *TargetLoweringObjectFileELF::getExplicitSectionGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ StringRef SectionName = GO->getSection();
+
+ // Infer section flags from the section name if we can.
+ Kind = getELFKindForNamedSection(SectionName, Kind);
+
+ StringRef Group = "";
+ unsigned Flags = getELFSectionFlags(Kind);
+ if (const Comdat *C = getELFComdat(GO)) {
+ Group = C->getName();
+ Flags |= ELF::SHF_GROUP;
+ }
+
+ // A section can have at most one associated section. Put each global with
+ // MD_associated in a unique section.
+ unsigned UniqueID = MCContext::GenericSectionID;
+ const MCSymbolELF *AssociatedSymbol = getAssociatedSymbol(GO, TM);
+ if (AssociatedSymbol) {
+ UniqueID = NextUniqueID++;
+ Flags |= ELF::SHF_LINK_ORDER;
+ }
+
+ MCSectionELF *Section = getContext().getELFSection(
+ SectionName, getELFSectionType(SectionName, Kind), Flags,
+ /*EntrySize=*/0, Group, UniqueID, AssociatedSymbol);
+ // Make sure that we did not get some other section with incompatible sh_link.
+ // This should not be possible due to UniqueID code above.
+ assert(Section->getAssociatedSymbol() == AssociatedSymbol);
+ return Section;
+}
+
+/// 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.isData())
+ return ".data";
+ assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+ return ".data.rel.ro";
+}
+
+static MCSectionELF *selectELFSectionForGlobal(
+ MCContext &Ctx, const GlobalObject *GO, SectionKind Kind, Mangler &Mang,
+ const TargetMachine &TM, bool EmitUniqueSection, unsigned Flags,
+ unsigned *NextUniqueID, const MCSymbolELF *AssociatedSymbol) {
+ 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 if (Kind.isMergeableConst16()) {
+ EntrySize = 16;
+ } else {
+ assert(Kind.isMergeableConst32() && "unknown data width");
+ EntrySize = 32;
+ }
+ }
+
+ StringRef Group = "";
+ if (const Comdat *C = getELFComdat(GO)) {
+ 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 = GO->getParent()->getDataLayout().getPreferredAlignment(
+ cast<GlobalVariable>(GO));
+
+ 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 (const auto *F = dyn_cast<Function>(GO)) {
+ const auto &OptionalPrefix = F->getSectionPrefix();
+ if (OptionalPrefix)
+ Name += *OptionalPrefix;
+ }
+
+ if (EmitUniqueSection && UniqueSectionNames) {
+ Name.push_back('.');
+ TM.getNameWithPrefix(Name, GO, Mang, true);
+ }
+ unsigned UniqueID = MCContext::GenericSectionID;
+ if (EmitUniqueSection && !UniqueSectionNames) {
+ UniqueID = *NextUniqueID;
+ (*NextUniqueID)++;
+ }
+ // Use 0 as the unique ID for execute-only text
+ if (Kind.isExecuteOnly())
+ UniqueID = 0;
+ return Ctx.getELFSection(Name, getELFSectionType(Name, Kind), Flags,
+ EntrySize, Group, UniqueID, AssociatedSymbol);
+}
+
+MCSection *TargetLoweringObjectFileELF::SelectSectionForGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ unsigned Flags = getELFSectionFlags(Kind);
+
+ // 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 |= GO->hasComdat();
+
+ const MCSymbolELF *AssociatedSymbol = getAssociatedSymbol(GO, TM);
+ if (AssociatedSymbol) {
+ EmitUniqueSection = true;
+ Flags |= ELF::SHF_LINK_ORDER;
+ }
+
+ MCSectionELF *Section = selectELFSectionForGlobal(
+ getContext(), GO, Kind, getMangler(), TM, EmitUniqueSection, Flags,
+ &NextUniqueID, AssociatedSymbol);
+ assert(Section->getAssociatedSymbol() == AssociatedSymbol);
+ return Section;
+}
+
+MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable(
+ const Function &F, 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;
+
+ return selectELFSectionForGlobal(getContext(), &F, SectionKind::getReadOnly(),
+ getMangler(), TM, EmitUniqueSection,
+ ELF::SHF_ALLOC, &NextUniqueID,
+ /* AssociatedSymbol */ nullptr);
+}
+
+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;
+}
+
+/// 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,
+ unsigned &Align) const {
+ if (Kind.isMergeableConst4() && MergeableConst4Section)
+ return MergeableConst4Section;
+ if (Kind.isMergeableConst8() && MergeableConst8Section)
+ return MergeableConst8Section;
+ if (Kind.isMergeableConst16() && MergeableConst16Section)
+ return MergeableConst16Section;
+ if (Kind.isMergeableConst32() && MergeableConst32Section)
+ return MergeableConst32Section;
+ if (Kind.isReadOnly())
+ return ReadOnlySection;
+
+ assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+ return DataRelROSection;
+}
+
+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;
+ 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 {
+ // The default scheme is .ctor / .dtor, so we have to invert the priority
+ // numbering.
+ 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);
+}
+
+MCSection *TargetLoweringObjectFileELF::getStaticCtorSection(
+ unsigned Priority, const MCSymbol *KeySym) const {
+ return getStaticStructorSection(getContext(), UseInitArray, true, Priority,
+ KeySym);
+}
+
+MCSection *TargetLoweringObjectFileELF::getStaticDtorSection(
+ unsigned Priority, const MCSymbol *KeySym) const {
+ return getStaticStructorSection(getContext(), UseInitArray, false, Priority,
+ KeySym);
+}
+
+const MCExpr *TargetLoweringObjectFileELF::lowerRelativeReference(
+ const GlobalValue *LHS, const GlobalValue *RHS,
+ const TargetMachine &TM) const {
+ // We may only use a PLT-relative relocation to refer to unnamed_addr
+ // functions.
+ if (!LHS->hasGlobalUnnamedAddr() || !LHS->getValueType()->isFunctionTy())
+ return nullptr;
+
+ // Basic sanity checks.
+ if (LHS->getType()->getPointerAddressSpace() != 0 ||
+ RHS->getType()->getPointerAddressSpace() != 0 || LHS->isThreadLocal() ||
+ RHS->isThreadLocal())
+ return nullptr;
+
+ return MCBinaryExpr::createSub(
+ MCSymbolRefExpr::create(TM.getSymbol(LHS), PLTRelativeVariantKind,
+ getContext()),
+ MCSymbolRefExpr::create(TM.getSymbol(RHS), getContext()), getContext());
+}
+
+void
+TargetLoweringObjectFileELF::InitializeELF(bool UseInitArray_) {
+ UseInitArray = UseInitArray_;
+ MCContext &Ctx = getContext();
+ if (!UseInitArray) {
+ 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);
+ return;
+ }
+
+ StaticCtorSection = Ctx.getELFSection(".init_array", ELF::SHT_INIT_ARRAY,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC);
+ StaticDtorSection = Ctx.getELFSection(".fini_array", ELF::SHT_FINI_ARRAY,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC);
+}
+
+//===----------------------------------------------------------------------===//
+// MachO
+//===----------------------------------------------------------------------===//
+
+TargetLoweringObjectFileMachO::TargetLoweringObjectFileMachO()
+ : TargetLoweringObjectFile() {
+ SupportIndirectSymViaGOTPCRel = true;
+}
+
+void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ TargetLoweringObjectFile::Initialize(Ctx, TM);
+ if (TM.getRelocationModel() == Reloc::Static) {
+ StaticCtorSection = Ctx.getMachOSection("__TEXT", "__constructor", 0,
+ SectionKind::getData());
+ StaticDtorSection = Ctx.getMachOSection("__TEXT", "__destructor", 0,
+ SectionKind::getData());
+ } else {
+ StaticCtorSection = Ctx.getMachOSection("__DATA", "__mod_init_func",
+ MachO::S_MOD_INIT_FUNC_POINTERS,
+ SectionKind::getData());
+ StaticDtorSection = Ctx.getMachOSection("__DATA", "__mod_term_func",
+ MachO::S_MOD_TERM_FUNC_POINTERS,
+ SectionKind::getData());
+ }
+}
+
+/// emitModuleFlags - Perform code emission for module flags.
+void TargetLoweringObjectFileMachO::emitModuleFlags(
+ MCStreamer &Streamer, ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
+ const TargetMachine &TM) const {
+ unsigned VersionVal = 0;
+ unsigned ImageInfoFlags = 0;
+ MDNode *LinkerOptions = nullptr;
+ StringRef SectionVal;
+
+ for (const auto &MFE : ModuleFlags) {
+ // Ignore flags with 'Require' behavior.
+ 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 Class Properties" ||
+ 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);
+ }
+ }
+
+ // Emit the linker options if present.
+ if (LinkerOptions) {
+ for (const auto &Option : LinkerOptions->operands()) {
+ SmallVector<std::string, 4> StrOptions;
+ for (const auto &Piece : cast<MDNode>(Option)->operands())
+ StrOptions.push_back(cast<MDString>(Piece)->getString());
+ Streamer.EmitLinkerOptions(StrOptions);
+ }
+ }
+
+ // The section is mandatory. If we don't have it, then we don't have GC info.
+ 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())
+ // If invalid, report the error with report_fatal_error.
+ report_fatal_error("Invalid section specifier '" + Section + "': " +
+ ErrorCode + ".");
+
+ // Get the section.
+ MCSectionMachO *S = getContext().getMachOSection(
+ Segment, Section, TAA, StubSize, SectionKind::getData());
+ 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.");
+}
+
+MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ // Parse the section specifier and create it if valid.
+ StringRef Segment, Section;
+ unsigned TAA = 0, StubSize = 0;
+ bool TAAParsed;
+
+ checkMachOComdat(GO);
+
+ std::string ErrorCode =
+ MCSectionMachO::ParseSectionSpecifier(GO->getSection(), Segment, Section,
+ TAA, TAAParsed, StubSize);
+ if (!ErrorCode.empty()) {
+ // If invalid, report the error with report_fatal_error.
+ report_fatal_error("Global variable '" + GO->getName() +
+ "' has an invalid section specifier '" +
+ GO->getSection() + "': " + ErrorCode + ".");
+ }
+
+ // Get the section.
+ 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.
+ if (!TAAParsed)
+ TAA = S->getTypeAndAttributes();
+
+ // Okay, now that we got the section, verify that the TAA & StubSize agree.
+ // If the user declared multiple globals with different section flags, we need
+ // to reject it here.
+ if (S->getTypeAndAttributes() != TAA || S->getStubSize() != StubSize) {
+ // If invalid, report the error with report_fatal_error.
+ report_fatal_error("Global variable '" + GO->getName() +
+ "' section type or attributes does not match previous"
+ " section specifier");
+ }
+
+ return S;
+}
+
+MCSection *TargetLoweringObjectFileMachO::SelectSectionForGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ checkMachOComdat(GO);
+
+ // Handle thread local data.
+ if (Kind.isThreadBSS()) return TLSBSSSection;
+ if (Kind.isThreadData()) return TLSDataSection;
+
+ if (Kind.isText())
+ return GO->isWeakForLinker() ? TextCoalSection : TextSection;
+
+ // If this is weak/linkonce, put this in a coalescable section, either in text
+ // or data depending on if it is writable.
+ if (GO->isWeakForLinker()) {
+ if (Kind.isReadOnly())
+ return ConstTextCoalSection;
+ return DataCoalSection;
+ }
+
+ // FIXME: Alignment check should be handled by section classifier.
+ if (Kind.isMergeable1ByteCString() &&
+ GO->getParent()->getDataLayout().getPreferredAlignment(
+ cast<GlobalVariable>(GO)) < 32)
+ return CStringSection;
+
+ // Do not put 16-bit arrays in the UString section if they have an
+ // externally visible label, this runs into issues with certain linker
+ // versions.
+ if (Kind.isMergeable2ByteCString() && !GO->hasExternalLinkage() &&
+ GO->getParent()->getDataLayout().getPreferredAlignment(
+ cast<GlobalVariable>(GO)) < 32)
+ return UStringSection;
+
+ // With MachO only variables whose corresponding symbol starts with 'l' or
+ // 'L' can be merged, so we only try merging GVs with private linkage.
+ if (GO->hasPrivateLinkage() && Kind.isMergeableConst()) {
+ if (Kind.isMergeableConst4())
+ return FourByteConstantSection;
+ if (Kind.isMergeableConst8())
+ return EightByteConstantSection;
+ if (Kind.isMergeableConst16())
+ return SixteenByteConstantSection;
+ }
+
+ // Otherwise, if it is readonly, but not something we can specially optimize,
+ // just drop it in .const.
+ if (Kind.isReadOnly())
+ return ReadOnlySection;
+
+ // If this is marked const, put it into a const section. But if the dynamic
+ // linker needs to write to it, put it in the data segment.
+ if (Kind.isReadOnlyWithRel())
+ return ConstDataSection;
+
+ // Put zero initialized globals with strong external linkage in the
+ // DATA, __common section with the .zerofill directive.
+ if (Kind.isBSSExtern())
+ return DataCommonSection;
+
+ // Put zero initialized globals with local linkage in __DATA,__bss directive
+ // with the .zerofill directive (aka .lcomm).
+ if (Kind.isBSSLocal())
+ return DataBSSSection;
+
+ // Otherwise, just drop the variable in the normal data section.
+ return DataSection;
+}
+
+MCSection *TargetLoweringObjectFileMachO::getSectionForConstant(
+ const DataLayout &DL, SectionKind Kind, const Constant *C,
+ unsigned &Align) const {
+ // If this constant requires a relocation, we have to put it in the data
+ // segment, not in the text segment.
+ if (Kind.isData() || Kind.isReadOnlyWithRel())
+ return ConstDataSection;
+
+ if (Kind.isMergeableConst4())
+ return FourByteConstantSection;
+ if (Kind.isMergeableConst8())
+ return EightByteConstantSection;
+ if (Kind.isMergeableConst16())
+ return SixteenByteConstantSection;
+ return ReadOnlySection; // .const
+}
+
+const MCExpr *TargetLoweringObjectFileMachO::getTTypeGlobalReference(
+ const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
+ MachineModuleInfo *MMI, MCStreamer &Streamer) const {
+ // The mach-o version of this method defaults to returning a stub reference.
+
+ if (Encoding & DW_EH_PE_indirect) {
+ MachineModuleInfoMachO &MachOMMI =
+ MMI->getObjFileInfo<MachineModuleInfoMachO>();
+
+ MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr", TM);
+
+ // Add information about the stub reference to MachOMMI so that the stub
+ // gets emitted by the asmprinter.
+ MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(SSym);
+ if (!StubSym.getPointer()) {
+ MCSymbol *Sym = TM.getSymbol(GV);
+ StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
+ }
+
+ return TargetLoweringObjectFile::
+ getTTypeReference(MCSymbolRefExpr::create(SSym, getContext()),
+ Encoding & ~DW_EH_PE_indirect, Streamer);
+ }
+
+ return TargetLoweringObjectFile::getTTypeGlobalReference(GV, Encoding, TM,
+ MMI, Streamer);
+}
+
+MCSymbol *TargetLoweringObjectFileMachO::getCFIPersonalitySymbol(
+ const GlobalValue *GV, const TargetMachine &TM,
+ MachineModuleInfo *MMI) const {
+ // The mach-o version of this method defaults to returning a stub reference.
+ MachineModuleInfoMachO &MachOMMI =
+ MMI->getObjFileInfo<MachineModuleInfoMachO>();
+
+ MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr", TM);
+
+ // Add information about the stub reference to MachOMMI so that the stub
+ // gets emitted by the asmprinter.
+ MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(SSym);
+ if (!StubSym.getPointer()) {
+ MCSymbol *Sym = TM.getSymbol(GV);
+ 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 {
+ // 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<MachineModuleInfoMachO>();
+ 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<MCSymbol *>(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);
+}
+
+static bool canUsePrivateLabel(const MCAsmInfo &AsmInfo,
+ const MCSection &Section) {
+ if (!AsmInfo.isSectionAtomizableBySymbols(Section))
+ return true;
+
+ // If it is not dead stripped, it is safe to use private labels.
+ const MCSectionMachO &SMO = cast<MCSectionMachO>(Section);
+ if (SMO.hasAttribute(MachO::S_ATTR_NO_DEAD_STRIP))
+ return true;
+
+ return false;
+}
+
+void TargetLoweringObjectFileMachO::getNameWithPrefix(
+ SmallVectorImpl<char> &OutName, const GlobalValue *GV,
+ const TargetMachine &TM) const {
+ bool CannotUsePrivateLabel = true;
+ if (auto *GO = GV->getBaseObject()) {
+ SectionKind GOKind = TargetLoweringObjectFile::getKindForGlobal(GO, TM);
+ const MCSection *TheSection = SectionForGlobal(GO, GOKind, TM);
+ CannotUsePrivateLabel =
+ !canUsePrivateLabel(*TM.getMCAsmInfo(), *TheSection);
+ }
+ getMangler().getNameWithPrefix(OutName, GV, CannotUsePrivateLabel);
+}
+
+//===----------------------------------------------------------------------===//
+// COFF
+//===----------------------------------------------------------------------===//
+
+static unsigned
+getCOFFSectionFlags(SectionKind K, const TargetMachine &TM) {
+ unsigned Flags = 0;
+ bool isThumb = TM.getTargetTriple().getArch() == Triple::thumb;
+
+ 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 |
+ (isThumb ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0);
+ 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;
+ }
+ }
+ return 0;
+}
+
+MCSection *TargetLoweringObjectFileCOFF::getExplicitSectionGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ int Selection = 0;
+ unsigned Characteristics = getCOFFSectionFlags(Kind, TM);
+ StringRef Name = GO->getSection();
+ StringRef COMDATSymName = "";
+ if (GO->hasComdat()) {
+ Selection = getSelectionForCOFF(GO);
+ const GlobalValue *ComdatGV;
+ if (Selection == COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE)
+ ComdatGV = getComdatGVForCOFF(GO);
+ else
+ ComdatGV = GO;
+
+ if (!ComdatGV->hasPrivateLinkage()) {
+ MCSymbol *Sym = TM.getSymbol(ComdatGV);
+ 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";
+}
+
+MCSection *TargetLoweringObjectFileCOFF::SelectSectionForGlobal(
+ const GlobalObject *GO, SectionKind Kind, 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;
+ if (Kind.isText())
+ EmitUniquedSection = TM.getFunctionSections();
+ else
+ EmitUniquedSection = TM.getDataSections();
+
+ if ((EmitUniquedSection && !Kind.isCommon()) || GO->hasComdat()) {
+ const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
+ unsigned Characteristics = getCOFFSectionFlags(Kind, TM);
+
+ Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
+ int Selection = getSelectionForCOFF(GO);
+ if (!Selection)
+ Selection = COFF::IMAGE_COMDAT_SELECT_NODUPLICATES;
+ const GlobalValue *ComdatGV;
+ if (GO->hasComdat())
+ ComdatGV = getComdatGVForCOFF(GO);
+ else
+ ComdatGV = GO;
+
+ unsigned UniqueID = MCContext::GenericSectionID;
+ if (EmitUniquedSection)
+ UniqueID = NextUniqueID++;
+
+ if (!ComdatGV->hasPrivateLinkage()) {
+ MCSymbol *Sym = TM.getSymbol(ComdatGV);
+ StringRef COMDATSymName = Sym->getName();
+ return getContext().getCOFFSection(Name, Characteristics, Kind,
+ COMDATSymName, Selection, UniqueID);
+ } else {
+ SmallString<256> TmpData;
+ getMangler().getNameWithPrefix(TmpData, GO, /*CannotUsePrivateLabel=*/true);
+ return getContext().getCOFFSection(Name, Characteristics, Kind, TmpData,
+ Selection, UniqueID);
+ }
+ }
+
+ if (Kind.isText())
+ return TextSection;
+
+ if (Kind.isThreadLocal())
+ return TLSDataSection;
+
+ if (Kind.isReadOnly() || Kind.isReadOnlyWithRel())
+ return ReadOnlySection;
+
+ // 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 DataSection;
+}
+
+void TargetLoweringObjectFileCOFF::getNameWithPrefix(
+ SmallVectorImpl<char> &OutName, const GlobalValue *GV,
+ const TargetMachine &TM) const {
+ bool CannotUsePrivateLabel = false;
+ if (GV->hasPrivateLinkage() &&
+ ((isa<Function>(GV) && TM.getFunctionSections()) ||
+ (isa<GlobalVariable>(GV) && TM.getDataSections())))
+ CannotUsePrivateLabel = true;
+
+ getMangler().getNameWithPrefix(OutName, GV, CannotUsePrivateLabel);
+}
+
+MCSection *TargetLoweringObjectFileCOFF::getSectionForJumpTable(
+ const Function &F, 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);
+ StringRef COMDATSymName = Sym->getName();
+
+ SectionKind Kind = SectionKind::getReadOnly();
+ const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
+ unsigned Characteristics = getCOFFSectionFlags(Kind, TM);
+ Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
+ unsigned UniqueID = NextUniqueID++;
+
+ return getContext().getCOFFSection(Name, Characteristics, Kind, COMDATSymName,
+ COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE, UniqueID);
+}
+
+void TargetLoweringObjectFileCOFF::emitModuleFlags(
+ MCStreamer &Streamer, ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
+ const TargetMachine &TM) const {
+ MDNode *LinkerOptions = nullptr;
+
+ for (const auto &MFE : ModuleFlags) {
+ StringRef Key = MFE.Key->getString();
+ if (Key == "Linker Options")
+ LinkerOptions = cast<MDNode>(MFE.Val);
+ }
+
+ if (LinkerOptions) {
+ // Emit the linker options to the linker .drectve section. According to the
+ // spec, this section is a space-separated string containing flags for
+ // linker.
+ MCSection *Sec = getDrectveSection();
+ Streamer.SwitchSection(Sec);
+ for (const auto &Option : LinkerOptions->operands()) {
+ for (const auto &Piece : cast<MDNode>(Option)->operands()) {
+ // Lead with a space for consistency with our dllexport implementation.
+ std::string Directive(" ");
+ Directive.append(cast<MDString>(Piece)->getString());
+ Streamer.EmitBytes(Directive);
+ }
+ }
+ }
+}
+
+void TargetLoweringObjectFileCOFF::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ TargetLoweringObjectFile::Initialize(Ctx, TM);
+ const Triple &T = TM.getTargetTriple();
+ 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::getData());
+ StaticDtorSection = Ctx.getCOFFSection(
+ ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+ COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
+ SectionKind::getData());
+ }
+}
+
+MCSection *TargetLoweringObjectFileCOFF::getStaticCtorSection(
+ unsigned Priority, const MCSymbol *KeySym) const {
+ return getContext().getAssociativeCOFFSection(
+ cast<MCSectionCOFF>(StaticCtorSection), KeySym, 0);
+}
+
+MCSection *TargetLoweringObjectFileCOFF::getStaticDtorSection(
+ unsigned Priority, const MCSymbol *KeySym) const {
+ return getContext().getAssociativeCOFFSection(
+ cast<MCSectionCOFF>(StaticDtorSection), KeySym, 0);
+}
+
+void TargetLoweringObjectFileCOFF::emitLinkerFlagsForGlobal(
+ raw_ostream &OS, const GlobalValue *GV) const {
+ emitLinkerFlagsForGlobalCOFF(OS, GV, getTargetTriple(), getMangler());
+}
+
+//===----------------------------------------------------------------------===//
+// Wasm
+//===----------------------------------------------------------------------===//
+
+static const Comdat *getWasmComdat(const GlobalValue *GV) {
+ const Comdat *C = GV->getComdat();
+ if (!C)
+ return nullptr;
+
+ if (C->getSelectionKind() != Comdat::Any)
+ report_fatal_error("Wasm COMDATs only support SelectionKind::Any, '" +
+ C->getName() + "' cannot be lowered.");
+
+ return C;
+}
+
+MCSection *TargetLoweringObjectFileWasm::getExplicitSectionGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+ llvm_unreachable("getExplicitSectionGlobal not yet implemented");
+ return nullptr;
+}
+
+static MCSectionWasm *
+selectWasmSectionForGlobal(MCContext &Ctx, const GlobalObject *GO,
+ SectionKind Kind, Mangler &Mang,
+ const TargetMachine &TM, bool EmitUniqueSection,
+ unsigned Flags, unsigned *NextUniqueID) {
+ StringRef Group = "";
+ if (getWasmComdat(GO))
+ llvm_unreachable("comdat not yet supported for wasm");
+
+ bool UniqueSectionNames = TM.getUniqueSectionNames();
+ SmallString<128> Name = getSectionPrefixForGlobal(Kind);
+
+ if (const auto *F = dyn_cast<Function>(GO)) {
+ const auto &OptionalPrefix = F->getSectionPrefix();
+ if (OptionalPrefix)
+ Name += *OptionalPrefix;
+ }
+
+ if (EmitUniqueSection && UniqueSectionNames) {
+ Name.push_back('.');
+ TM.getNameWithPrefix(Name, GO, Mang, true);
+ }
+ unsigned UniqueID = MCContext::GenericSectionID;
+ if (EmitUniqueSection && !UniqueSectionNames) {
+ UniqueID = *NextUniqueID;
+ (*NextUniqueID)++;
+ }
+ return Ctx.getWasmSection(Name, /*Type=*/0, Flags,
+ Group, UniqueID);
+}
+
+MCSection *TargetLoweringObjectFileWasm::SelectSectionForGlobal(
+ const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
+
+ if (Kind.isCommon())
+ report_fatal_error("mergable sections not supported yet on wasm");
+
+ // 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 (Kind.isText())
+ EmitUniqueSection = TM.getFunctionSections();
+ else
+ EmitUniqueSection = TM.getDataSections();
+ EmitUniqueSection |= GO->hasComdat();
+
+ return selectWasmSectionForGlobal(getContext(), GO, Kind, getMangler(), TM,
+ EmitUniqueSection, /*Flags=*/0,
+ &NextUniqueID);
+}
+
+bool TargetLoweringObjectFileWasm::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;
+}
+
+const MCExpr *TargetLoweringObjectFileWasm::lowerRelativeReference(
+ const GlobalValue *LHS, const GlobalValue *RHS,
+ const TargetMachine &TM) const {
+ // We may only use a PLT-relative relocation to refer to unnamed_addr
+ // functions.
+ if (!LHS->hasGlobalUnnamedAddr() || !LHS->getValueType()->isFunctionTy())
+ return nullptr;
+
+ // Basic sanity checks.
+ if (LHS->getType()->getPointerAddressSpace() != 0 ||
+ RHS->getType()->getPointerAddressSpace() != 0 || LHS->isThreadLocal() ||
+ RHS->isThreadLocal())
+ return nullptr;
+
+ return MCBinaryExpr::createSub(
+ MCSymbolRefExpr::create(TM.getSymbol(LHS), MCSymbolRefExpr::VK_None,
+ getContext()),
+ MCSymbolRefExpr::create(TM.getSymbol(RHS), getContext()), getContext());
+}
+
+void
+TargetLoweringObjectFileWasm::InitializeWasm() {
+ // TODO: Initialize StaticCtorSection and StaticDtorSection.
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-31 19:23:46 +0000