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-rw-r--r--contrib/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp961
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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/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/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;
+
+//===----------------------------------------------------------------------===//
+// ELF
+//===----------------------------------------------------------------------===//
+
+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,
+ SectionKind::getDataRel(),
+ 0, Label->getName());
+ unsigned Size = TM.getSubtargetImpl()->getDataLayout()->getPointerSize();
+ Streamer.SwitchSection(Sec);
+ Streamer.EmitValueToAlignment(
+ TM.getSubtargetImpl()->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);
+
+ // 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, 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) {
+ // 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.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) {
+
+ 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.isWriteable())
+ Flags |= ELF::SHF_WRITE;
+
+ if (K.isThreadLocal())
+ Flags |= ELF::SHF_TLS;
+
+ // K.isMergeableConst() is left out to honour PR4650
+ if (K.isMergeableCString() || K.isMergeableConst4() ||
+ K.isMergeableConst8() || K.isMergeableConst16())
+ 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();
+
+ // 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(GV)) {
+ Group = C->getName();
+ Flags |= ELF::SHF_GROUP;
+ }
+ return getContext().getELFSection(SectionName,
+ getELFSectionType(SectionName, Kind), Flags,
+ Kind, /*EntrySize=*/0, Group);
+}
+
+/// getSectionPrefixForGlobal - 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.";
+
+ 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 {
+ // 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;
+ }
+
+ 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()) {
+
+ // 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<GlobalVariable>(GV));
+
+ const char *SizeSpec = ".rodata.str1.";
+ if (Kind.isMergeable2ByteCString())
+ SizeSpec = ".rodata.str2.";
+ else if (Kind.isMergeable4ByteCString())
+ SizeSpec = ".rodata.str4.";
+ else
+ assert(Kind.isMergeable1ByteCString() && "unknown string width");
+
+
+ std::string Name = SizeSpec + utostr(Align);
+ return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
+ ELF::SHF_ALLOC |
+ ELF::SHF_MERGE |
+ ELF::SHF_STRINGS,
+ Kind);
+ }
+
+ if (Kind.isMergeableConst()) {
+ if (Kind.isMergeableConst4() && MergeableConst4Section)
+ return MergeableConst4Section;
+ if (Kind.isMergeableConst8() && MergeableConst8Section)
+ return MergeableConst8Section;
+ if (Kind.isMergeableConst16() && MergeableConst16Section)
+ return MergeableConst16Section;
+ return ReadOnlySection; // .const
+ }
+
+ if (Kind.isReadOnly()) return ReadOnlySection;
+
+ if (Kind.isThreadData()) return TLSDataSection;
+ if (Kind.isThreadBSS()) return TLSBSSSection;
+
+ // 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;
+
+ if (Kind.isDataNoRel()) return DataSection;
+ if (Kind.isDataRelLocal()) return DataRelLocalSection;
+ if (Kind.isDataRel()) return DataRelSection;
+ if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
+
+ assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+ return DataRelROSection;
+}
+
+/// getSectionForConstant - Given a mergeable constant with the
+/// specified size and relocation information, return a section that it
+/// should be placed in.
+const MCSection *
+TargetLoweringObjectFileELF::getSectionForConstant(SectionKind Kind,
+ const 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;
+ SectionKind Kind = SectionKind::getDataRel();
+ 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, Kind, 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,
+ SectionKind::getDataRel());
+ StaticDtorSection =
+ getContext().getELFSection(".fini_array", ELF::SHT_FINI_ARRAY,
+ ELF::SHF_WRITE |
+ ELF::SHF_ALLOC,
+ SectionKind::getDataRel());
+}
+
+//===----------------------------------------------------------------------===//
+// 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();
+}
+
+/// emitModuleFlags - Perform code emission for module flags.
+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;
+
+ // 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 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 (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
+ MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
+ SmallVector<std::string, 4> StrOptions;
+
+ // Convert to strings.
+ 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);
+ }
+ }
+
+ // 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.
+ 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 {
+ // Parse the section specifier and create it if valid.
+ 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()) {
+ // If invalid, report the error with report_fatal_error.
+ report_fatal_error("Global variable '" + GV->getName() +
+ "' has an invalid section specifier '" +
+ GV->getSection() + "': " + ErrorCode + ".");
+ }
+
+ // Get the section.
+ const 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 '" + 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);
+
+ // Handle thread local data.
+ if (Kind.isThreadBSS()) return TLSBSSSection;
+ if (Kind.isThreadData()) return TLSDataSection;
+
+ if (Kind.isText())
+ return GV->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 (GV->isWeakForLinker()) {
+ if (Kind.isReadOnly())
+ return ConstTextCoalSection;
+ return DataCoalSection;
+ }
+
+ // FIXME: Alignment check should be handled by section classifier.
+ if (Kind.isMergeable1ByteCString() &&
+ TM.getSubtargetImpl()->getDataLayout()->getPreferredAlignment(
+ cast<GlobalVariable>(GV)) < 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() && !GV->hasExternalLinkage() &&
+ TM.getSubtargetImpl()->getDataLayout()->getPreferredAlignment(
+ cast<GlobalVariable>(GV)) < 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 (GV->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;
+}
+
+const MCSection *
+TargetLoweringObjectFileMachO::getSectionForConstant(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())
+ 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, Mangler &Mang,
+ 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, "$non_lazy_ptr", Mang, TM);
+
+ // Add information about the stub reference to MachOMMI so that the stub
+ // gets emitted by the asmprinter.
+ MachineModuleInfoImpl::StubValueTy &StubSym =
+ GV->hasHiddenVisibility() ? MachOMMI.getHiddenGVStubEntry(SSym) :
+ MachOMMI.getGVStubEntry(SSym);
+ if (!StubSym.getPointer()) {
+ MCSymbol *Sym = TM.getSymbol(GV, Mang);
+ StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
+ }
+
+ return TargetLoweringObjectFile::
+ getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()),
+ Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
+ }
+
+ return TargetLoweringObjectFile::getTTypeGlobalReference(GV, Encoding, Mang,
+ TM, MMI, Streamer);
+}
+
+MCSymbol *TargetLoweringObjectFileMachO::getCFIPersonalitySymbol(
+ const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM,
+ MachineModuleInfo *MMI) const {
+ // The mach-o version of this method defaults to returning a stub reference.
+ MachineModuleInfoMachO &MachOMMI =
+ MMI->getObjFileInfo<MachineModuleInfoMachO>();
+
+ MCSymbol *SSym = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr", Mang, 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, Mang);
+ StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
+ }
+
+ return SSym;
+}
+
+//===----------------------------------------------------------------------===//
+// COFF
+//===----------------------------------------------------------------------===//
+
+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->isWeakForLinker() || GV->hasComdat()) && !Kind.isCommon()) {
+ 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 {
+ // 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 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()) {
+ 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;
+
+ // 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;
+}
+
+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;
+
+ // Look for the "Linker Options" flag, since it's the only one we support.
+ 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;
+
+ // 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();
+ 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();
+ // Lead with a space for consistency with our dllexport implementation.
+ std::string Escaped(" ");
+ if (!Op.startswith("\"") && (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);
+ }
+ }
+}
+
+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);
+}
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