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diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp
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+//===-- llvm/Target/TargetLoweringObjectFile.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/Target/TargetLoweringObjectFile.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Support/Mangler.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// Generic Code
+//===----------------------------------------------------------------------===//
+
+TargetLoweringObjectFile::TargetLoweringObjectFile() : Ctx(0) {
+ TextSection = 0;
+ DataSection = 0;
+ BSSSection = 0;
+ ReadOnlySection = 0;
+ StaticCtorSection = 0;
+ StaticDtorSection = 0;
+ LSDASection = 0;
+ EHFrameSection = 0;
+
+ DwarfAbbrevSection = 0;
+ DwarfInfoSection = 0;
+ DwarfLineSection = 0;
+ DwarfFrameSection = 0;
+ DwarfPubNamesSection = 0;
+ DwarfPubTypesSection = 0;
+ DwarfDebugInlineSection = 0;
+ DwarfStrSection = 0;
+ DwarfLocSection = 0;
+ DwarfARangesSection = 0;
+ DwarfRangesSection = 0;
+ DwarfMacroInfoSection = 0;
+}
+
+TargetLoweringObjectFile::~TargetLoweringObjectFile() {
+}
+
+static bool isSuitableForBSS(const GlobalVariable *GV) {
+ Constant *C = GV->getInitializer();
+
+ // Must have zero initializer.
+ if (!C->isNullValue())
+ return false;
+
+ // Leave constant zeros in readonly constant sections, so they can be shared.
+ if (GV->isConstant())
+ return false;
+
+ // If the global has an explicit section specified, don't put it in BSS.
+ if (!GV->getSection().empty())
+ return false;
+
+ // If -nozero-initialized-in-bss is specified, don't ever use BSS.
+ if (NoZerosInBSS)
+ return false;
+
+ // Otherwise, put it in BSS!
+ return true;
+}
+
+/// IsNullTerminatedString - Return true if the specified constant (which is
+/// known to have a type that is an array of 1/2/4 byte elements) ends with a
+/// nul value and contains no other nuls in it.
+static bool IsNullTerminatedString(const Constant *C) {
+ const ArrayType *ATy = cast<ArrayType>(C->getType());
+
+ // First check: is we have constant array of i8 terminated with zero
+ if (const ConstantArray *CVA = dyn_cast<ConstantArray>(C)) {
+ if (ATy->getNumElements() == 0) return false;
+
+ ConstantInt *Null =
+ dyn_cast<ConstantInt>(CVA->getOperand(ATy->getNumElements()-1));
+ if (Null == 0 || Null->getZExtValue() != 0)
+ return false; // Not null terminated.
+
+ // Verify that the null doesn't occur anywhere else in the string.
+ for (unsigned i = 0, e = ATy->getNumElements()-1; i != e; ++i)
+ // Reject constantexpr elements etc.
+ if (!isa<ConstantInt>(CVA->getOperand(i)) ||
+ CVA->getOperand(i) == Null)
+ return false;
+ return true;
+ }
+
+ // Another possibility: [1 x i8] zeroinitializer
+ if (isa<ConstantAggregateZero>(C))
+ return ATy->getNumElements() == 1;
+
+ return false;
+}
+
+/// getKindForGlobal - This is a top-level target-independent classifier for
+/// a global variable. Given an global variable and information from TM, it
+/// classifies the global in a variety of ways that make various target
+/// implementations simpler. The target implementation is free to ignore this
+/// extra info of course.
+SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV,
+ const TargetMachine &TM){
+ assert(!GV->isDeclaration() && !GV->hasAvailableExternallyLinkage() &&
+ "Can only be used for global definitions");
+
+ Reloc::Model ReloModel = TM.getRelocationModel();
+
+ // Early exit - functions should be always in text sections.
+ const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
+ if (GVar == 0)
+ return SectionKind::getText();
+
+ // Handle thread-local data first.
+ if (GVar->isThreadLocal()) {
+ if (isSuitableForBSS(GVar))
+ return SectionKind::getThreadBSS();
+ return SectionKind::getThreadData();
+ }
+
+ // Variable can be easily put to BSS section.
+ if (isSuitableForBSS(GVar))
+ return SectionKind::getBSS();
+
+ Constant *C = GVar->getInitializer();
+
+ // If the global is marked constant, we can put it into a mergable section,
+ // a mergable string section, or general .data if it contains relocations.
+ if (GVar->isConstant()) {
+ // If the initializer for the global contains something that requires a
+ // relocation, then we may have to drop this into a wriable data section
+ // even though it is marked const.
+ switch (C->getRelocationInfo()) {
+ default: llvm_unreachable("unknown relocation info kind");
+ case Constant::NoRelocation:
+ // If initializer is a null-terminated string, put it in a "cstring"
+ // section of the right width.
+ if (const ArrayType *ATy = dyn_cast<ArrayType>(C->getType())) {
+ if (const IntegerType *ITy =
+ dyn_cast<IntegerType>(ATy->getElementType())) {
+ if ((ITy->getBitWidth() == 8 || ITy->getBitWidth() == 16 ||
+ ITy->getBitWidth() == 32) &&
+ IsNullTerminatedString(C)) {
+ if (ITy->getBitWidth() == 8)
+ return SectionKind::getMergeable1ByteCString();
+ if (ITy->getBitWidth() == 16)
+ return SectionKind::getMergeable2ByteCString();
+
+ assert(ITy->getBitWidth() == 32 && "Unknown width");
+ return SectionKind::getMergeable4ByteCString();
+ }
+ }
+ }
+
+ // Otherwise, just drop it into a mergable constant section. If we have
+ // a section for this size, use it, otherwise use the arbitrary sized
+ // mergable section.
+ switch (TM.getTargetData()->getTypeAllocSize(C->getType())) {
+ case 4: return SectionKind::getMergeableConst4();
+ case 8: return SectionKind::getMergeableConst8();
+ case 16: return SectionKind::getMergeableConst16();
+ default: return SectionKind::getMergeableConst();
+ }
+
+ case Constant::LocalRelocation:
+ // In static relocation model, the linker will resolve all addresses, so
+ // the relocation entries will actually be constants by the time the app
+ // starts up. However, we can't put this into a mergable section, because
+ // the linker doesn't take relocations into consideration when it tries to
+ // merge entries in the section.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::getReadOnly();
+
+ // Otherwise, the dynamic linker needs to fix it up, put it in the
+ // writable data.rel.local section.
+ return SectionKind::getReadOnlyWithRelLocal();
+
+ case Constant::GlobalRelocations:
+ // In static relocation model, the linker will resolve all addresses, so
+ // the relocation entries will actually be constants by the time the app
+ // starts up. However, we can't put this into a mergable section, because
+ // the linker doesn't take relocations into consideration when it tries to
+ // merge entries in the section.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::getReadOnly();
+
+ // Otherwise, the dynamic linker needs to fix it up, put it in the
+ // writable data.rel section.
+ return SectionKind::getReadOnlyWithRel();
+ }
+ }
+
+ // Okay, this isn't a constant. If the initializer for the global is going
+ // to require a runtime relocation by the dynamic linker, put it into a more
+ // specific section to improve startup time of the app. This coalesces these
+ // globals together onto fewer pages, improving the locality of the dynamic
+ // linker.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::getDataNoRel();
+
+ switch (C->getRelocationInfo()) {
+ default: llvm_unreachable("unknown relocation info kind");
+ case Constant::NoRelocation:
+ return SectionKind::getDataNoRel();
+ case Constant::LocalRelocation:
+ return SectionKind::getDataRelLocal();
+ case Constant::GlobalRelocations:
+ return SectionKind::getDataRel();
+ }
+}
+
+/// SectionForGlobal - This method computes the appropriate section to emit
+/// the specified global variable or function definition. This should not
+/// be passed external (or available externally) globals.
+const MCSection *TargetLoweringObjectFile::
+SectionForGlobal(const GlobalValue *GV, SectionKind Kind, Mangler *Mang,
+ const TargetMachine &TM) const {
+ // Select section name.
+ if (GV->hasSection())
+ return getExplicitSectionGlobal(GV, Kind, Mang, TM);
+
+
+ // Use default section depending on the 'type' of global
+ return SelectSectionForGlobal(GV, Kind, Mang, TM);
+}
+
+
+// Lame default implementation. Calculate the section name for global.
+const MCSection *
+TargetLoweringObjectFile::SelectSectionForGlobal(const GlobalValue *GV,
+ SectionKind Kind,
+ Mangler *Mang,
+ const TargetMachine &TM) const{
+ assert(!Kind.isThreadLocal() && "Doesn't support TLS");
+
+ if (Kind.isText())
+ return getTextSection();
+
+ if (Kind.isBSS() && BSSSection != 0)
+ return BSSSection;
+
+ if (Kind.isReadOnly() && ReadOnlySection != 0)
+ return ReadOnlySection;
+
+ return getDataSection();
+}
+
+/// getSectionForConstant - Given a mergable constant with the
+/// specified size and relocation information, return a section that it
+/// should be placed in.
+const MCSection *
+TargetLoweringObjectFile::getSectionForConstant(SectionKind Kind) const {
+ if (Kind.isReadOnly() && ReadOnlySection != 0)
+ return ReadOnlySection;
+
+ return DataSection;
+}
+
+/// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a
+/// pc-relative reference to the specified global variable from exception
+/// handling information. In addition to the symbol, this returns
+/// by-reference:
+///
+/// IsIndirect - True if the returned symbol is actually a stub that contains
+/// the address of the symbol, false if the symbol is the global itself.
+///
+/// IsPCRel - True if the symbol reference is already pc-relative, false if
+/// the caller needs to subtract off the address of the reference from the
+/// symbol.
+///
+const MCExpr *TargetLoweringObjectFile::
+getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
+ MachineModuleInfo *MMI,
+ bool &IsIndirect, bool &IsPCRel) const {
+ // The generic implementation of this just returns a direct reference to the
+ // symbol.
+ IsIndirect = false;
+ IsPCRel = false;
+
+ SmallString<128> Name;
+ Mang->getNameWithPrefix(Name, GV, false);
+ return MCSymbolRefExpr::Create(Name.str(), getContext());
+}
+
+
+//===----------------------------------------------------------------------===//
+// ELF
+//===----------------------------------------------------------------------===//
+typedef StringMap<const MCSectionELF*> ELFUniqueMapTy;
+
+TargetLoweringObjectFileELF::~TargetLoweringObjectFileELF() {
+ // If we have the section uniquing map, free it.
+ delete (ELFUniqueMapTy*)UniquingMap;
+}
+
+const MCSection *TargetLoweringObjectFileELF::
+getELFSection(StringRef Section, unsigned Type, unsigned Flags,
+ SectionKind Kind, bool IsExplicit) const {
+ if (UniquingMap == 0)
+ UniquingMap = new ELFUniqueMapTy();
+ ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)UniquingMap;
+
+ // Do the lookup, if we have a hit, return it.
+ const MCSectionELF *&Entry = Map[Section];
+ if (Entry) return Entry;
+
+ return Entry = MCSectionELF::Create(Section, Type, Flags, Kind, IsExplicit,
+ getContext());
+}
+
+void TargetLoweringObjectFileELF::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ if (UniquingMap != 0)
+ ((ELFUniqueMapTy*)UniquingMap)->clear();
+ TargetLoweringObjectFile::Initialize(Ctx, TM);
+
+ BSSSection =
+ getELFSection(".bss", MCSectionELF::SHT_NOBITS,
+ MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
+ SectionKind::getBSS());
+
+ TextSection =
+ getELFSection(".text", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_EXECINSTR | MCSectionELF::SHF_ALLOC,
+ SectionKind::getText());
+
+ DataSection =
+ getELFSection(".data", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
+ SectionKind::getDataRel());
+
+ ReadOnlySection =
+ getELFSection(".rodata", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC,
+ SectionKind::getReadOnly());
+
+ TLSDataSection =
+ getELFSection(".tdata", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
+ MCSectionELF::SHF_WRITE, SectionKind::getThreadData());
+
+ TLSBSSSection =
+ getELFSection(".tbss", MCSectionELF::SHT_NOBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
+ MCSectionELF::SHF_WRITE, SectionKind::getThreadBSS());
+
+ DataRelSection =
+ getELFSection(".data.rel", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getDataRel());
+
+ DataRelLocalSection =
+ getELFSection(".data.rel.local", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getDataRelLocal());
+
+ DataRelROSection =
+ getELFSection(".data.rel.ro", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getReadOnlyWithRel());
+
+ DataRelROLocalSection =
+ getELFSection(".data.rel.ro.local", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getReadOnlyWithRelLocal());
+
+ MergeableConst4Section =
+ getELFSection(".rodata.cst4", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+ SectionKind::getMergeableConst4());
+
+ MergeableConst8Section =
+ getELFSection(".rodata.cst8", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+ SectionKind::getMergeableConst8());
+
+ MergeableConst16Section =
+ getELFSection(".rodata.cst16", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+ SectionKind::getMergeableConst16());
+
+ StaticCtorSection =
+ getELFSection(".ctors", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getDataRel());
+
+ StaticDtorSection =
+ getELFSection(".dtors", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getDataRel());
+
+ // Exception Handling Sections.
+
+ // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
+ // it contains relocatable pointers. In PIC mode, this is probably a big
+ // runtime hit for C++ apps. Either the contents of the LSDA need to be
+ // adjusted or this should be a data section.
+ LSDASection =
+ getELFSection(".gcc_except_table", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC, SectionKind::getReadOnly());
+ EHFrameSection =
+ getELFSection(".eh_frame", MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+ SectionKind::getDataRel());
+
+ // Debug Info Sections.
+ DwarfAbbrevSection =
+ getELFSection(".debug_abbrev", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfInfoSection =
+ getELFSection(".debug_info", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfLineSection =
+ getELFSection(".debug_line", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfFrameSection =
+ getELFSection(".debug_frame", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfPubNamesSection =
+ getELFSection(".debug_pubnames", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfPubTypesSection =
+ getELFSection(".debug_pubtypes", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfStrSection =
+ getELFSection(".debug_str", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfLocSection =
+ getELFSection(".debug_loc", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfARangesSection =
+ getELFSection(".debug_aranges", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfRangesSection =
+ getELFSection(".debug_ranges", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+ DwarfMacroInfoSection =
+ getELFSection(".debug_macinfo", MCSectionELF::SHT_PROGBITS, 0,
+ SectionKind::getMetadata());
+}
+
+
+static SectionKind
+getELFKindForNamedSection(const char *Name, SectionKind K) {
+ if (Name[0] != '.') return K;
+
+ // Some lame default implementation based on some magic section names.
+ if (strcmp(Name, ".bss") == 0 ||
+ strncmp(Name, ".bss.", 5) == 0 ||
+ strncmp(Name, ".gnu.linkonce.b.", 16) == 0 ||
+ strncmp(Name, ".llvm.linkonce.b.", 17) == 0 ||
+ strcmp(Name, ".sbss") == 0 ||
+ strncmp(Name, ".sbss.", 6) == 0 ||
+ strncmp(Name, ".gnu.linkonce.sb.", 17) == 0 ||
+ strncmp(Name, ".llvm.linkonce.sb.", 18) == 0)
+ return SectionKind::getBSS();
+
+ if (strcmp(Name, ".tdata") == 0 ||
+ strncmp(Name, ".tdata.", 7) == 0 ||
+ strncmp(Name, ".gnu.linkonce.td.", 17) == 0 ||
+ strncmp(Name, ".llvm.linkonce.td.", 18) == 0)
+ return SectionKind::getThreadData();
+
+ if (strcmp(Name, ".tbss") == 0 ||
+ strncmp(Name, ".tbss.", 6) == 0 ||
+ strncmp(Name, ".gnu.linkonce.tb.", 17) == 0 ||
+ strncmp(Name, ".llvm.linkonce.tb.", 18) == 0)
+ return SectionKind::getThreadBSS();
+
+ return K;
+}
+
+
+static unsigned
+getELFSectionType(const char *Name, SectionKind K) {
+
+ if (strcmp(Name, ".init_array") == 0)
+ return MCSectionELF::SHT_INIT_ARRAY;
+
+ if (strcmp(Name, ".fini_array") == 0)
+ return MCSectionELF::SHT_FINI_ARRAY;
+
+ if (strcmp(Name, ".preinit_array") == 0)
+ return MCSectionELF::SHT_PREINIT_ARRAY;
+
+ if (K.isBSS() || K.isThreadBSS())
+ return MCSectionELF::SHT_NOBITS;
+
+ return MCSectionELF::SHT_PROGBITS;
+}
+
+
+static unsigned
+getELFSectionFlags(SectionKind K) {
+ unsigned Flags = 0;
+
+ if (!K.isMetadata())
+ Flags |= MCSectionELF::SHF_ALLOC;
+
+ if (K.isText())
+ Flags |= MCSectionELF::SHF_EXECINSTR;
+
+ if (K.isWriteable())
+ Flags |= MCSectionELF::SHF_WRITE;
+
+ if (K.isThreadLocal())
+ Flags |= MCSectionELF::SHF_TLS;
+
+ // K.isMergeableConst() is left out to honour PR4650
+ if (K.isMergeableCString() || K.isMergeableConst4() ||
+ K.isMergeableConst8() || K.isMergeableConst16())
+ Flags |= MCSectionELF::SHF_MERGE;
+
+ if (K.isMergeableCString())
+ Flags |= MCSectionELF::SHF_STRINGS;
+
+ return Flags;
+}
+
+
+const MCSection *TargetLoweringObjectFileELF::
+getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+ Mangler *Mang, const TargetMachine &TM) const {
+ const char *SectionName = GV->getSection().c_str();
+
+ // Infer section flags from the section name if we can.
+ Kind = getELFKindForNamedSection(SectionName, Kind);
+
+ return getELFSection(SectionName,
+ getELFSectionType(SectionName, Kind),
+ getELFSectionFlags(Kind), Kind, true);
+}
+
+static const char *getSectionPrefixForUniqueGlobal(SectionKind Kind) {
+ if (Kind.isText()) return ".gnu.linkonce.t.";
+ if (Kind.isReadOnly()) return ".gnu.linkonce.r.";
+
+ if (Kind.isThreadData()) return ".gnu.linkonce.td.";
+ if (Kind.isThreadBSS()) return ".gnu.linkonce.tb.";
+
+ if (Kind.isBSS()) return ".gnu.linkonce.b.";
+ if (Kind.isDataNoRel()) return ".gnu.linkonce.d.";
+ if (Kind.isDataRelLocal()) return ".gnu.linkonce.d.rel.local.";
+ if (Kind.isDataRel()) return ".gnu.linkonce.d.rel.";
+ if (Kind.isReadOnlyWithRelLocal()) return ".gnu.linkonce.d.rel.ro.local.";
+
+ assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+ return ".gnu.linkonce.d.rel.ro.";
+}
+
+const MCSection *TargetLoweringObjectFileELF::
+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 = getSectionPrefixForUniqueGlobal(Kind);
+ std::string Name = Mang->makeNameProper(GV->getNameStr());
+
+ return getELFSection((Prefix+Name).c_str(),
+ getELFSectionType((Prefix+Name).c_str(), Kind),
+ getELFSectionFlags(Kind),
+ Kind);
+ }
+
+ 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.getTargetData()->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 getELFSection(Name.c_str(), MCSectionELF::SHT_PROGBITS,
+ MCSectionELF::SHF_ALLOC |
+ MCSectionELF::SHF_MERGE |
+ MCSectionELF::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;
+
+ if (Kind.isBSS()) 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 {
+ 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;
+}
+
+//===----------------------------------------------------------------------===//
+// MachO
+//===----------------------------------------------------------------------===//
+
+typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
+
+TargetLoweringObjectFileMachO::~TargetLoweringObjectFileMachO() {
+ // If we have the MachO uniquing map, free it.
+ delete (MachOUniqueMapTy*)UniquingMap;
+}
+
+
+const MCSectionMachO *TargetLoweringObjectFileMachO::
+getMachOSection(const StringRef &Segment, const StringRef &Section,
+ unsigned TypeAndAttributes,
+ unsigned Reserved2, SectionKind Kind) const {
+ // We unique sections by their segment/section pair. The returned section
+ // may not have the same flags as the requested section, if so this should be
+ // diagnosed by the client as an error.
+
+ // Create the map if it doesn't already exist.
+ if (UniquingMap == 0)
+ UniquingMap = new MachOUniqueMapTy();
+ MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)UniquingMap;
+
+ // Form the name to look up.
+ SmallString<64> Name;
+ Name += Segment;
+ Name.push_back(',');
+ Name += Section;
+
+ // Do the lookup, if we have a hit, return it.
+ const MCSectionMachO *&Entry = Map[Name.str()];
+ if (Entry) return Entry;
+
+ // Otherwise, return a new section.
+ return Entry = MCSectionMachO::Create(Segment, Section, TypeAndAttributes,
+ Reserved2, Kind, getContext());
+}
+
+
+void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ if (UniquingMap != 0)
+ ((MachOUniqueMapTy*)UniquingMap)->clear();
+ TargetLoweringObjectFile::Initialize(Ctx, TM);
+
+ TextSection // .text
+ = getMachOSection("__TEXT", "__text",
+ MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
+ SectionKind::getText());
+ DataSection // .data
+ = getMachOSection("__DATA", "__data", 0, SectionKind::getDataRel());
+
+ CStringSection // .cstring
+ = getMachOSection("__TEXT", "__cstring", MCSectionMachO::S_CSTRING_LITERALS,
+ SectionKind::getMergeable1ByteCString());
+ UStringSection
+ = getMachOSection("__TEXT","__ustring", 0,
+ SectionKind::getMergeable2ByteCString());
+ FourByteConstantSection // .literal4
+ = getMachOSection("__TEXT", "__literal4", MCSectionMachO::S_4BYTE_LITERALS,
+ SectionKind::getMergeableConst4());
+ EightByteConstantSection // .literal8
+ = getMachOSection("__TEXT", "__literal8", MCSectionMachO::S_8BYTE_LITERALS,
+ SectionKind::getMergeableConst8());
+
+ // ld_classic doesn't support .literal16 in 32-bit mode, and ld64 falls back
+ // to using it in -static mode.
+ SixteenByteConstantSection = 0;
+ if (TM.getRelocationModel() != Reloc::Static &&
+ TM.getTargetData()->getPointerSize() == 32)
+ SixteenByteConstantSection = // .literal16
+ getMachOSection("__TEXT", "__literal16",MCSectionMachO::S_16BYTE_LITERALS,
+ SectionKind::getMergeableConst16());
+
+ ReadOnlySection // .const
+ = getMachOSection("__TEXT", "__const", 0, SectionKind::getReadOnly());
+
+ TextCoalSection
+ = getMachOSection("__TEXT", "__textcoal_nt",
+ MCSectionMachO::S_COALESCED |
+ MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
+ SectionKind::getText());
+ ConstTextCoalSection
+ = getMachOSection("__TEXT", "__const_coal", MCSectionMachO::S_COALESCED,
+ SectionKind::getText());
+ ConstDataCoalSection
+ = getMachOSection("__DATA","__const_coal", MCSectionMachO::S_COALESCED,
+ SectionKind::getText());
+ ConstDataSection // .const_data
+ = getMachOSection("__DATA", "__const", 0,
+ SectionKind::getReadOnlyWithRel());
+ DataCoalSection
+ = getMachOSection("__DATA","__datacoal_nt", MCSectionMachO::S_COALESCED,
+ SectionKind::getDataRel());
+
+
+ LazySymbolPointerSection
+ = getMachOSection("__DATA", "__la_symbol_ptr",
+ MCSectionMachO::S_LAZY_SYMBOL_POINTERS,
+ SectionKind::getMetadata());
+ NonLazySymbolPointerSection
+ = getMachOSection("__DATA", "__nl_symbol_ptr",
+ MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
+ SectionKind::getMetadata());
+
+ if (TM.getRelocationModel() == Reloc::Static) {
+ StaticCtorSection
+ = getMachOSection("__TEXT", "__constructor", 0,SectionKind::getDataRel());
+ StaticDtorSection
+ = getMachOSection("__TEXT", "__destructor", 0, SectionKind::getDataRel());
+ } else {
+ StaticCtorSection
+ = getMachOSection("__DATA", "__mod_init_func",
+ MCSectionMachO::S_MOD_INIT_FUNC_POINTERS,
+ SectionKind::getDataRel());
+ StaticDtorSection
+ = getMachOSection("__DATA", "__mod_term_func",
+ MCSectionMachO::S_MOD_TERM_FUNC_POINTERS,
+ SectionKind::getDataRel());
+ }
+
+ // Exception Handling.
+ LSDASection = getMachOSection("__DATA", "__gcc_except_tab", 0,
+ SectionKind::getDataRel());
+ EHFrameSection =
+ getMachOSection("__TEXT", "__eh_frame",
+ MCSectionMachO::S_COALESCED |
+ MCSectionMachO::S_ATTR_NO_TOC |
+ MCSectionMachO::S_ATTR_STRIP_STATIC_SYMS |
+ MCSectionMachO::S_ATTR_LIVE_SUPPORT,
+ SectionKind::getReadOnly());
+
+ // Debug Information.
+ DwarfAbbrevSection =
+ getMachOSection("__DWARF", "__debug_abbrev", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfInfoSection =
+ getMachOSection("__DWARF", "__debug_info", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfLineSection =
+ getMachOSection("__DWARF", "__debug_line", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfFrameSection =
+ getMachOSection("__DWARF", "__debug_frame", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfPubNamesSection =
+ getMachOSection("__DWARF", "__debug_pubnames", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfPubTypesSection =
+ getMachOSection("__DWARF", "__debug_pubtypes", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfStrSection =
+ getMachOSection("__DWARF", "__debug_str", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfLocSection =
+ getMachOSection("__DWARF", "__debug_loc", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfARangesSection =
+ getMachOSection("__DWARF", "__debug_aranges", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfRangesSection =
+ getMachOSection("__DWARF", "__debug_ranges", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfMacroInfoSection =
+ getMachOSection("__DWARF", "__debug_macinfo", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+ DwarfDebugInlineSection =
+ getMachOSection("__DWARF", "__debug_inlined", MCSectionMachO::S_ATTR_DEBUG,
+ SectionKind::getMetadata());
+}
+
+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, StubSize;
+ std::string ErrorCode =
+ MCSectionMachO::ParseSectionSpecifier(GV->getSection(), Segment, Section,
+ TAA, StubSize);
+ if (!ErrorCode.empty()) {
+ // If invalid, report the error with llvm_report_error.
+ llvm_report_error("Global variable '" + GV->getNameStr() +
+ "' has an invalid section specifier '" + GV->getSection()+
+ "': " + ErrorCode + ".");
+ // Fall back to dropping it into the data section.
+ return DataSection;
+ }
+
+ // Get the section.
+ const MCSectionMachO *S =
+ getMachOSection(Segment, Section, TAA, StubSize, Kind);
+
+ // 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 llvm_report_error.
+ llvm_report_error("Global variable '" + GV->getNameStr() +
+ "' 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 {
+ assert(!Kind.isThreadLocal() && "Darwin doesn't support TLS");
+
+ 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() ||
+ Kind.isMergeable2ByteCString()) {
+ if (TM.getTargetData()->getPreferredAlignment(
+ cast<GlobalVariable>(GV)) < 32) {
+ if (Kind.isMergeable1ByteCString())
+ return CStringSection;
+ assert(Kind.isMergeable2ByteCString());
+ 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;
+
+ // 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())
+ 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.
+ const std::string &Name = Mang->getMangledName(GV);
+ if (Name[0] == 'L' || Name[0] == 'l')
+ return false;
+ }
+
+ return true;
+}
+
+const MCExpr *TargetLoweringObjectFileMachO::
+getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
+ MachineModuleInfo *MMI,
+ bool &IsIndirect, bool &IsPCRel) const {
+ // The mach-o version of this method defaults to returning a stub reference.
+ IsIndirect = true;
+ IsPCRel = false;
+
+ SmallString<128> Name;
+ Mang->getNameWithPrefix(Name, GV, true);
+ Name += "$non_lazy_ptr";
+ return MCSymbolRefExpr::Create(Name.str(), getContext());
+}
+
+
+//===----------------------------------------------------------------------===//
+// COFF
+//===----------------------------------------------------------------------===//
+
+typedef StringMap<const MCSectionCOFF*> COFFUniqueMapTy;
+
+TargetLoweringObjectFileCOFF::~TargetLoweringObjectFileCOFF() {
+ delete (COFFUniqueMapTy*)UniquingMap;
+}
+
+
+const MCSection *TargetLoweringObjectFileCOFF::
+getCOFFSection(const char *Name, bool isDirective, SectionKind Kind) const {
+ // Create the map if it doesn't already exist.
+ if (UniquingMap == 0)
+ UniquingMap = new MachOUniqueMapTy();
+ COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)UniquingMap;
+
+ // Do the lookup, if we have a hit, return it.
+ const MCSectionCOFF *&Entry = Map[Name];
+ if (Entry) return Entry;
+
+ return Entry = MCSectionCOFF::Create(Name, isDirective, Kind, getContext());
+}
+
+void TargetLoweringObjectFileCOFF::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ if (UniquingMap != 0)
+ ((COFFUniqueMapTy*)UniquingMap)->clear();
+ TargetLoweringObjectFile::Initialize(Ctx, TM);
+ TextSection = getCOFFSection("\t.text", true, SectionKind::getText());
+ DataSection = getCOFFSection("\t.data", true, SectionKind::getDataRel());
+ StaticCtorSection =
+ getCOFFSection(".ctors", false, SectionKind::getDataRel());
+ StaticDtorSection =
+ getCOFFSection(".dtors", false, SectionKind::getDataRel());
+
+ // FIXME: We're emitting LSDA info into a readonly section on COFF, even
+ // though it contains relocatable pointers. In PIC mode, this is probably a
+ // big runtime hit for C++ apps. Either the contents of the LSDA need to be
+ // adjusted or this should be a data section.
+ LSDASection =
+ getCOFFSection(".gcc_except_table", false, SectionKind::getReadOnly());
+ EHFrameSection =
+ getCOFFSection(".eh_frame", false, SectionKind::getDataRel());
+
+ // Debug info.
+ // FIXME: Don't use 'directive' mode here.
+ DwarfAbbrevSection =
+ getCOFFSection("\t.section\t.debug_abbrev,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfInfoSection =
+ getCOFFSection("\t.section\t.debug_info,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfLineSection =
+ getCOFFSection("\t.section\t.debug_line,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfFrameSection =
+ getCOFFSection("\t.section\t.debug_frame,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfPubNamesSection =
+ getCOFFSection("\t.section\t.debug_pubnames,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfPubTypesSection =
+ getCOFFSection("\t.section\t.debug_pubtypes,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfStrSection =
+ getCOFFSection("\t.section\t.debug_str,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfLocSection =
+ getCOFFSection("\t.section\t.debug_loc,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfARangesSection =
+ getCOFFSection("\t.section\t.debug_aranges,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfRangesSection =
+ getCOFFSection("\t.section\t.debug_ranges,\"dr\"",
+ true, SectionKind::getMetadata());
+ DwarfMacroInfoSection =
+ getCOFFSection("\t.section\t.debug_macinfo,\"dr\"",
+ true, SectionKind::getMetadata());
+}
+
+const MCSection *TargetLoweringObjectFileCOFF::
+getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+ Mangler *Mang, const TargetMachine &TM) const {
+ return getCOFFSection(GV->getSection().c_str(), false, Kind);
+}
+
+static const char *getCOFFSectionPrefixForUniqueGlobal(SectionKind Kind) {
+ if (Kind.isText())
+ return ".text$linkonce";
+ if (Kind.isWriteable())
+ return ".data$linkonce";
+ return ".rdata$linkonce";
+}
+
+
+const MCSection *TargetLoweringObjectFileCOFF::
+SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+ Mangler *Mang, const TargetMachine &TM) const {
+ assert(!Kind.isThreadLocal() && "Doesn't support TLS");
+
+ // 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);
+ std::string Name = Mang->makeNameProper(GV->getNameStr());
+ return getCOFFSection((Prefix+Name).c_str(), false, Kind);
+ }
+
+ if (Kind.isText())
+ return getTextSection();
+
+ return getDataSection();
+}
+
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