mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-30 21:29:28 +00:00
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165726 91177308-0d34-0410-b5e6-96231b3b80d8
751 lines
27 KiB
C++
751 lines
27 KiB
C++
//===-- llvm/CodeGen/TargetLoweringObjectFileImpl.cpp - Object File Info --===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements classes used to handle lowerings specific to common
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// object file formats.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
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#include "llvm/Constants.h"
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#include "llvm/DerivedTypes.h"
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#include "llvm/Function.h"
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#include "llvm/GlobalVariable.h"
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#include "llvm/Module.h"
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#include "llvm/CodeGen/MachineModuleInfoImpls.h"
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#include "llvm/MC/MCContext.h"
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#include "llvm/MC/MCExpr.h"
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#include "llvm/MC/MCSectionMachO.h"
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#include "llvm/MC/MCSectionELF.h"
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#include "llvm/MC/MCSectionCOFF.h"
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#include "llvm/MC/MCStreamer.h"
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#include "llvm/MC/MCSymbol.h"
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#include "llvm/Target/Mangler.h"
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#include "llvm/DataLayout.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetOptions.h"
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#include "llvm/Support/Dwarf.h"
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#include "llvm/Support/ELF.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/ADT/Triple.h"
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using namespace llvm;
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using namespace dwarf;
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//===----------------------------------------------------------------------===//
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// ELF
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//===----------------------------------------------------------------------===//
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MCSymbol *
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TargetLoweringObjectFileELF::getCFIPersonalitySymbol(const GlobalValue *GV,
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Mangler *Mang,
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MachineModuleInfo *MMI) const {
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unsigned Encoding = getPersonalityEncoding();
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switch (Encoding & 0x70) {
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default:
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report_fatal_error("We do not support this DWARF encoding yet!");
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case dwarf::DW_EH_PE_absptr:
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return Mang->getSymbol(GV);
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case dwarf::DW_EH_PE_pcrel: {
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return getContext().GetOrCreateSymbol(StringRef("DW.ref.") +
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Mang->getSymbol(GV)->getName());
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}
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}
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}
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void TargetLoweringObjectFileELF::emitPersonalityValue(MCStreamer &Streamer,
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const TargetMachine &TM,
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const MCSymbol *Sym) const {
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SmallString<64> NameData("DW.ref.");
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NameData += Sym->getName();
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MCSymbol *Label = getContext().GetOrCreateSymbol(NameData);
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Streamer.EmitSymbolAttribute(Label, MCSA_Hidden);
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Streamer.EmitSymbolAttribute(Label, MCSA_Weak);
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StringRef Prefix = ".data.";
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NameData.insert(NameData.begin(), Prefix.begin(), Prefix.end());
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unsigned Flags = ELF::SHF_ALLOC | ELF::SHF_WRITE | ELF::SHF_GROUP;
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const MCSection *Sec = getContext().getELFSection(NameData,
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ELF::SHT_PROGBITS,
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Flags,
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SectionKind::getDataRel(),
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0, Label->getName());
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unsigned Size = TM.getDataLayout()->getPointerSize(0);
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Streamer.SwitchSection(Sec);
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Streamer.EmitValueToAlignment(TM.getDataLayout()->getPointerABIAlignment(0));
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Streamer.EmitSymbolAttribute(Label, MCSA_ELF_TypeObject);
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const MCExpr *E = MCConstantExpr::Create(Size, getContext());
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Streamer.EmitELFSize(Label, E);
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Streamer.EmitLabel(Label);
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Streamer.EmitSymbolValue(Sym, Size);
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}
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static SectionKind
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getELFKindForNamedSection(StringRef Name, SectionKind K) {
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// N.B.: The defaults used in here are no the same ones used in MC.
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// We follow gcc, MC follows gas. For example, given ".section .eh_frame",
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// both gas and MC will produce a section with no flags. Given
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// section(".eh_frame") gcc will produce:
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//
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// .section .eh_frame,"a",@progbits
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if (Name.empty() || Name[0] != '.') return K;
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// Some lame default implementation based on some magic section names.
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if (Name == ".bss" ||
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Name.startswith(".bss.") ||
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Name.startswith(".gnu.linkonce.b.") ||
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Name.startswith(".llvm.linkonce.b.") ||
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Name == ".sbss" ||
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Name.startswith(".sbss.") ||
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Name.startswith(".gnu.linkonce.sb.") ||
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Name.startswith(".llvm.linkonce.sb."))
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return SectionKind::getBSS();
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if (Name == ".tdata" ||
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Name.startswith(".tdata.") ||
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Name.startswith(".gnu.linkonce.td.") ||
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Name.startswith(".llvm.linkonce.td."))
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return SectionKind::getThreadData();
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if (Name == ".tbss" ||
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Name.startswith(".tbss.") ||
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Name.startswith(".gnu.linkonce.tb.") ||
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Name.startswith(".llvm.linkonce.tb."))
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return SectionKind::getThreadBSS();
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return K;
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}
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static unsigned getELFSectionType(StringRef Name, SectionKind K) {
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if (Name == ".init_array")
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return ELF::SHT_INIT_ARRAY;
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if (Name == ".fini_array")
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return ELF::SHT_FINI_ARRAY;
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if (Name == ".preinit_array")
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return ELF::SHT_PREINIT_ARRAY;
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if (K.isBSS() || K.isThreadBSS())
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return ELF::SHT_NOBITS;
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return ELF::SHT_PROGBITS;
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}
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static unsigned
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getELFSectionFlags(SectionKind K) {
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unsigned Flags = 0;
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if (!K.isMetadata())
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Flags |= ELF::SHF_ALLOC;
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if (K.isText())
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Flags |= ELF::SHF_EXECINSTR;
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if (K.isWriteable())
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Flags |= ELF::SHF_WRITE;
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if (K.isThreadLocal())
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Flags |= ELF::SHF_TLS;
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// K.isMergeableConst() is left out to honour PR4650
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if (K.isMergeableCString() || K.isMergeableConst4() ||
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K.isMergeableConst8() || K.isMergeableConst16())
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Flags |= ELF::SHF_MERGE;
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if (K.isMergeableCString())
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Flags |= ELF::SHF_STRINGS;
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return Flags;
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}
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const MCSection *TargetLoweringObjectFileELF::
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getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
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Mangler *Mang, const TargetMachine &TM) const {
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StringRef SectionName = GV->getSection();
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// Infer section flags from the section name if we can.
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Kind = getELFKindForNamedSection(SectionName, Kind);
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return getContext().getELFSection(SectionName,
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getELFSectionType(SectionName, Kind),
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getELFSectionFlags(Kind), Kind);
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}
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/// getSectionPrefixForGlobal - Return the section prefix name used by options
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/// FunctionsSections and DataSections.
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static const char *getSectionPrefixForGlobal(SectionKind Kind) {
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if (Kind.isText()) return ".text.";
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if (Kind.isReadOnly()) return ".rodata.";
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if (Kind.isBSS()) return ".bss.";
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if (Kind.isThreadData()) return ".tdata.";
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if (Kind.isThreadBSS()) return ".tbss.";
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if (Kind.isDataNoRel()) return ".data.";
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if (Kind.isDataRelLocal()) return ".data.rel.local.";
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if (Kind.isDataRel()) return ".data.rel.";
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if (Kind.isReadOnlyWithRelLocal()) return ".data.rel.ro.local.";
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assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
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return ".data.rel.ro.";
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}
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const MCSection *TargetLoweringObjectFileELF::
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SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
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Mangler *Mang, const TargetMachine &TM) const {
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// If we have -ffunction-section or -fdata-section then we should emit the
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// global value to a uniqued section specifically for it.
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bool EmitUniquedSection;
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if (Kind.isText())
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EmitUniquedSection = TM.getFunctionSections();
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else
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EmitUniquedSection = TM.getDataSections();
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// If this global is linkonce/weak and the target handles this by emitting it
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// into a 'uniqued' section name, create and return the section now.
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if ((GV->isWeakForLinker() || EmitUniquedSection) &&
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!Kind.isCommon()) {
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const char *Prefix;
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Prefix = getSectionPrefixForGlobal(Kind);
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SmallString<128> Name(Prefix, Prefix+strlen(Prefix));
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MCSymbol *Sym = Mang->getSymbol(GV);
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Name.append(Sym->getName().begin(), Sym->getName().end());
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StringRef Group = "";
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unsigned Flags = getELFSectionFlags(Kind);
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if (GV->isWeakForLinker()) {
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Group = Sym->getName();
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Flags |= ELF::SHF_GROUP;
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}
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return getContext().getELFSection(Name.str(),
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getELFSectionType(Name.str(), Kind),
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Flags, Kind, 0, Group);
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}
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if (Kind.isText()) return TextSection;
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if (Kind.isMergeable1ByteCString() ||
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Kind.isMergeable2ByteCString() ||
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Kind.isMergeable4ByteCString()) {
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// We also need alignment here.
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// FIXME: this is getting the alignment of the character, not the
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// alignment of the global!
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unsigned Align =
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TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV));
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const char *SizeSpec = ".rodata.str1.";
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if (Kind.isMergeable2ByteCString())
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SizeSpec = ".rodata.str2.";
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else if (Kind.isMergeable4ByteCString())
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SizeSpec = ".rodata.str4.";
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else
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assert(Kind.isMergeable1ByteCString() && "unknown string width");
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std::string Name = SizeSpec + utostr(Align);
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return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
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ELF::SHF_ALLOC |
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ELF::SHF_MERGE |
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ELF::SHF_STRINGS,
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Kind);
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}
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if (Kind.isMergeableConst()) {
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if (Kind.isMergeableConst4() && MergeableConst4Section)
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return MergeableConst4Section;
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if (Kind.isMergeableConst8() && MergeableConst8Section)
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return MergeableConst8Section;
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if (Kind.isMergeableConst16() && MergeableConst16Section)
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return MergeableConst16Section;
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return ReadOnlySection; // .const
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}
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if (Kind.isReadOnly()) return ReadOnlySection;
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if (Kind.isThreadData()) return TLSDataSection;
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if (Kind.isThreadBSS()) return TLSBSSSection;
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// Note: we claim that common symbols are put in BSSSection, but they are
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// really emitted with the magic .comm directive, which creates a symbol table
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// entry but not a section.
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if (Kind.isBSS() || Kind.isCommon()) return BSSSection;
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if (Kind.isDataNoRel()) return DataSection;
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if (Kind.isDataRelLocal()) return DataRelLocalSection;
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if (Kind.isDataRel()) return DataRelSection;
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if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
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assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
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return DataRelROSection;
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}
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/// getSectionForConstant - Given a mergeable constant with the
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/// specified size and relocation information, return a section that it
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/// should be placed in.
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const MCSection *TargetLoweringObjectFileELF::
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getSectionForConstant(SectionKind Kind) const {
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if (Kind.isMergeableConst4() && MergeableConst4Section)
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return MergeableConst4Section;
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if (Kind.isMergeableConst8() && MergeableConst8Section)
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return MergeableConst8Section;
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if (Kind.isMergeableConst16() && MergeableConst16Section)
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return MergeableConst16Section;
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if (Kind.isReadOnly())
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return ReadOnlySection;
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if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
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assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
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return DataRelROSection;
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}
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const MCExpr *TargetLoweringObjectFileELF::
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getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
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MachineModuleInfo *MMI,
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unsigned Encoding, MCStreamer &Streamer) const {
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if (Encoding & dwarf::DW_EH_PE_indirect) {
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MachineModuleInfoELF &ELFMMI = MMI->getObjFileInfo<MachineModuleInfoELF>();
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SmallString<128> Name;
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Mang->getNameWithPrefix(Name, GV, true);
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Name += ".DW.stub";
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// Add information about the stub reference to ELFMMI so that the stub
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// gets emitted by the asmprinter.
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MCSymbol *SSym = getContext().GetOrCreateSymbol(Name.str());
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MachineModuleInfoImpl::StubValueTy &StubSym = ELFMMI.getGVStubEntry(SSym);
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if (StubSym.getPointer() == 0) {
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MCSymbol *Sym = Mang->getSymbol(GV);
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StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
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}
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return TargetLoweringObjectFile::
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getExprForDwarfReference(SSym, Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
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}
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return TargetLoweringObjectFile::
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getExprForDwarfGlobalReference(GV, Mang, MMI, Encoding, Streamer);
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}
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const MCSection *
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TargetLoweringObjectFileELF::getStaticCtorSection(unsigned Priority) const {
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// The default scheme is .ctor / .dtor, so we have to invert the priority
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// numbering.
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if (Priority == 65535)
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return StaticCtorSection;
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if (UseInitArray) {
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std::string Name = std::string(".init_array.") + utostr(Priority);
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return getContext().getELFSection(Name, ELF::SHT_INIT_ARRAY,
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ELF::SHF_ALLOC | ELF::SHF_WRITE,
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SectionKind::getDataRel());
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} else {
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std::string Name = std::string(".ctors.") + utostr(65535 - Priority);
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return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
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ELF::SHF_ALLOC |ELF::SHF_WRITE,
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SectionKind::getDataRel());
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}
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}
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const MCSection *
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TargetLoweringObjectFileELF::getStaticDtorSection(unsigned Priority) const {
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// The default scheme is .ctor / .dtor, so we have to invert the priority
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// numbering.
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if (Priority == 65535)
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return StaticDtorSection;
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if (UseInitArray) {
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std::string Name = std::string(".fini_array.") + utostr(Priority);
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return getContext().getELFSection(Name, ELF::SHT_FINI_ARRAY,
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ELF::SHF_ALLOC | ELF::SHF_WRITE,
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SectionKind::getDataRel());
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} else {
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std::string Name = std::string(".dtors.") + utostr(65535 - Priority);
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return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
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ELF::SHF_ALLOC |ELF::SHF_WRITE,
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SectionKind::getDataRel());
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}
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}
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void
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TargetLoweringObjectFileELF::InitializeELF(bool UseInitArray_) {
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UseInitArray = UseInitArray_;
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if (!UseInitArray)
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return;
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StaticCtorSection =
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getContext().getELFSection(".init_array", ELF::SHT_INIT_ARRAY,
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ELF::SHF_WRITE |
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ELF::SHF_ALLOC,
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SectionKind::getDataRel());
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StaticDtorSection =
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getContext().getELFSection(".fini_array", ELF::SHT_FINI_ARRAY,
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ELF::SHF_WRITE |
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ELF::SHF_ALLOC,
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SectionKind::getDataRel());
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}
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//===----------------------------------------------------------------------===//
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// MachO
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//===----------------------------------------------------------------------===//
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/// emitModuleFlags - Emit the module flags that specify the garbage collection
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/// information.
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void TargetLoweringObjectFileMachO::
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emitModuleFlags(MCStreamer &Streamer,
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ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
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Mangler *Mang, const TargetMachine &TM) const {
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unsigned VersionVal = 0;
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unsigned ImageInfoFlags = 0;
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StringRef SectionVal;
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for (ArrayRef<Module::ModuleFlagEntry>::iterator
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i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
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const Module::ModuleFlagEntry &MFE = *i;
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// Ignore flags with 'Require' behavior.
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if (MFE.Behavior == Module::Require)
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continue;
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StringRef Key = MFE.Key->getString();
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Value *Val = MFE.Val;
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if (Key == "Objective-C Image Info Version")
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VersionVal = cast<ConstantInt>(Val)->getZExtValue();
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else if (Key == "Objective-C Garbage Collection" ||
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Key == "Objective-C GC Only" ||
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Key == "Objective-C Is Simulated")
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ImageInfoFlags |= cast<ConstantInt>(Val)->getZExtValue();
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else if (Key == "Objective-C Image Info Section")
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SectionVal = cast<MDString>(Val)->getString();
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}
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// The section is mandatory. If we don't have it, then we don't have GC info.
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if (SectionVal.empty()) return;
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StringRef Segment, Section;
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unsigned TAA = 0, StubSize = 0;
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bool TAAParsed;
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std::string ErrorCode =
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MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
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TAA, TAAParsed, StubSize);
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if (!ErrorCode.empty())
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// If invalid, report the error with report_fatal_error.
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report_fatal_error("Invalid section specifier '" + Section + "': " +
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ErrorCode + ".");
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// Get the section.
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const MCSectionMachO *S =
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getContext().getMachOSection(Segment, Section, TAA, StubSize,
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SectionKind::getDataNoRel());
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Streamer.SwitchSection(S);
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Streamer.EmitLabel(getContext().
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GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
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Streamer.EmitIntValue(VersionVal, 4);
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Streamer.EmitIntValue(ImageInfoFlags, 4);
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Streamer.AddBlankLine();
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}
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const MCSection *TargetLoweringObjectFileMachO::
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getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
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Mangler *Mang, const TargetMachine &TM) const {
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// Parse the section specifier and create it if valid.
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StringRef Segment, Section;
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unsigned TAA = 0, StubSize = 0;
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bool TAAParsed;
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std::string ErrorCode =
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MCSectionMachO::ParseSectionSpecifier(GV->getSection(), Segment, Section,
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TAA, TAAParsed, StubSize);
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if (!ErrorCode.empty()) {
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// If invalid, report the error with report_fatal_error.
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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 {
|
|
|
|
// 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.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.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV)) < 32)
|
|
return UStringSection;
|
|
|
|
if (Kind.isMergeableConst()) {
|
|
if (Kind.isMergeableConst4())
|
|
return FourByteConstantSection;
|
|
if (Kind.isMergeableConst8())
|
|
return EightByteConstantSection;
|
|
if (Kind.isMergeableConst16() && SixteenByteConstantSection)
|
|
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 {
|
|
// 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() && SixteenByteConstantSection)
|
|
return SixteenByteConstantSection;
|
|
return ReadOnlySection; // .const
|
|
}
|
|
|
|
/// shouldEmitUsedDirectiveFor - This hook allows targets to selectively decide
|
|
/// not to emit the UsedDirective for some symbols in llvm.used.
|
|
// FIXME: REMOVE this (rdar://7071300)
|
|
bool TargetLoweringObjectFileMachO::
|
|
shouldEmitUsedDirectiveFor(const GlobalValue *GV, Mangler *Mang) const {
|
|
/// On Darwin, internally linked data beginning with "L" or "l" does not have
|
|
/// the directive emitted (this occurs in ObjC metadata).
|
|
if (!GV) return false;
|
|
|
|
// Check whether the mangled name has the "Private" or "LinkerPrivate" prefix.
|
|
if (GV->hasLocalLinkage() && !isa<Function>(GV)) {
|
|
// FIXME: ObjC metadata is currently emitted as internal symbols that have
|
|
// \1L and \0l prefixes on them. Fix them to be Private/LinkerPrivate and
|
|
// this horrible hack can go away.
|
|
MCSymbol *Sym = Mang->getSymbol(GV);
|
|
if (Sym->getName()[0] == 'L' || Sym->getName()[0] == 'l')
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
const MCExpr *TargetLoweringObjectFileMachO::
|
|
getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
|
|
MachineModuleInfo *MMI, unsigned Encoding,
|
|
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>();
|
|
|
|
SmallString<128> Name;
|
|
Mang->getNameWithPrefix(Name, GV, true);
|
|
Name += "$non_lazy_ptr";
|
|
|
|
// Add information about the stub reference to MachOMMI so that the stub
|
|
// gets emitted by the asmprinter.
|
|
MCSymbol *SSym = getContext().GetOrCreateSymbol(Name.str());
|
|
MachineModuleInfoImpl::StubValueTy &StubSym =
|
|
GV->hasHiddenVisibility() ? MachOMMI.getHiddenGVStubEntry(SSym) :
|
|
MachOMMI.getGVStubEntry(SSym);
|
|
if (StubSym.getPointer() == 0) {
|
|
MCSymbol *Sym = Mang->getSymbol(GV);
|
|
StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
|
|
}
|
|
|
|
return TargetLoweringObjectFile::
|
|
getExprForDwarfReference(SSym, Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
|
|
}
|
|
|
|
return TargetLoweringObjectFile::
|
|
getExprForDwarfGlobalReference(GV, Mang, MMI, Encoding, Streamer);
|
|
}
|
|
|
|
MCSymbol *TargetLoweringObjectFileMachO::
|
|
getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
|
|
MachineModuleInfo *MMI) const {
|
|
// The mach-o version of this method defaults to returning a stub reference.
|
|
MachineModuleInfoMachO &MachOMMI =
|
|
MMI->getObjFileInfo<MachineModuleInfoMachO>();
|
|
|
|
SmallString<128> Name;
|
|
Mang->getNameWithPrefix(Name, GV, true);
|
|
Name += "$non_lazy_ptr";
|
|
|
|
// Add information about the stub reference to MachOMMI so that the stub
|
|
// gets emitted by the asmprinter.
|
|
MCSymbol *SSym = getContext().GetOrCreateSymbol(Name.str());
|
|
MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(SSym);
|
|
if (StubSym.getPointer() == 0) {
|
|
MCSymbol *Sym = Mang->getSymbol(GV);
|
|
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())
|
|
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;
|
|
}
|
|
|
|
const MCSection *TargetLoweringObjectFileCOFF::
|
|
getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
|
|
Mangler *Mang, const TargetMachine &TM) const {
|
|
return getContext().getCOFFSection(GV->getSection(),
|
|
getCOFFSectionFlags(Kind),
|
|
Kind);
|
|
}
|
|
|
|
static const char *getCOFFSectionPrefixForUniqueGlobal(SectionKind Kind) {
|
|
if (Kind.isText())
|
|
return ".text$";
|
|
if (Kind.isBSS ())
|
|
return ".bss$";
|
|
if (Kind.isThreadLocal())
|
|
return ".tls$";
|
|
if (Kind.isWriteable())
|
|
return ".data$";
|
|
return ".rdata$";
|
|
}
|
|
|
|
|
|
const MCSection *TargetLoweringObjectFileCOFF::
|
|
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
|
|
Mangler *Mang, const TargetMachine &TM) const {
|
|
|
|
// If this global is linkonce/weak and the target handles this by emitting it
|
|
// into a 'uniqued' section name, create and return the section now.
|
|
if (GV->isWeakForLinker()) {
|
|
const char *Prefix = getCOFFSectionPrefixForUniqueGlobal(Kind);
|
|
SmallString<128> Name(Prefix, Prefix+strlen(Prefix));
|
|
MCSymbol *Sym = Mang->getSymbol(GV);
|
|
Name.append(Sym->getName().begin() + 1, Sym->getName().end());
|
|
|
|
unsigned Characteristics = getCOFFSectionFlags(Kind);
|
|
|
|
Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
|
|
|
|
return getContext().getCOFFSection(Name.str(), Characteristics,
|
|
COFF::IMAGE_COMDAT_SELECT_ANY, Kind);
|
|
}
|
|
|
|
if (Kind.isText())
|
|
return getTextSection();
|
|
|
|
if (Kind.isThreadLocal())
|
|
return getTLSDataSection();
|
|
|
|
return getDataSection();
|
|
}
|
|
|