X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FTargetLoweringObjectFile.cpp;h=56b7b69de0bdcffbebbd20c1a88f4d938266626c;hb=57c68f972cbc97c220989167bed6b5ef902c56df;hp=84b1b93ab01b11ea9123f9a09a79cd32c4142ac6;hpb=35c3531754c392a533921a465a22f67f7e8fb743;p=oota-llvm.git diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp index 84b1b93ab01..56b7b69de0b 100644 --- a/lib/Target/TargetLoweringObjectFile.cpp +++ b/lib/Target/TargetLoweringObjectFile.cpp @@ -18,66 +18,55 @@ #include "llvm/Function.h" #include "llvm/GlobalVariable.h" #include "llvm/MC/MCContext.h" -#include "llvm/MC/MCSectionMachO.h" -#include "llvm/MC/MCSectionELF.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/Target/Mangler.h" #include "llvm/Target/TargetData.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetOptions.h" -#include "llvm/Support/Mangler.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/raw_ostream.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; +/// Initialize - this method must be called before any actual lowering is +/// done. This specifies the current context for codegen, and gives the +/// lowering implementations a chance to set up their default sections. +void TargetLoweringObjectFile::Initialize(MCContext &ctx, + const TargetMachine &TM) { + Ctx = &ctx; + InitMCObjectFileInfo(TM.getTargetTriple(), + TM.getRelocationModel(), TM.getCodeModel(), *Ctx); } - + TargetLoweringObjectFile::~TargetLoweringObjectFile() { } static bool isSuitableForBSS(const GlobalVariable *GV) { - Constant *C = GV->getInitializer(); - + const 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; } @@ -86,17 +75,17 @@ static bool isSuitableForBSS(const GlobalVariable *GV) { /// 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(C->getType()); - + ArrayType *ATy = cast(C->getType()); + // First check: is we have constant array of i8 terminated with zero if (const ConstantArray *CVA = dyn_cast(C)) { if (ATy->getNumElements() == 0) return false; ConstantInt *Null = dyn_cast(CVA->getOperand(ATy->getNumElements()-1)); - if (Null == 0 || Null->getZExtValue() != 0) + if (Null == 0 || !Null->isZero()) 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. @@ -113,6 +102,18 @@ static bool IsNullTerminatedString(const Constant *C) { return false; } +MCSymbol *TargetLoweringObjectFile:: +getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang, + MachineModuleInfo *MMI) const { + return Mang->getSymbol(GV); +} + +void TargetLoweringObjectFile::emitPersonalityValue(MCStreamer &Streamer, + const TargetMachine &TM, + const MCSymbol *Sym) const { +} + + /// 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 @@ -122,14 +123,14 @@ 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(GV); if (GVar == 0) return SectionKind::getText(); - + // Handle thread-local data first. if (GVar->isThreadLocal()) { if (isSuitableForBSS(GVar)) @@ -137,12 +138,21 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, return SectionKind::getThreadData(); } + // Variables with common linkage always get classified as common. + if (GVar->hasCommonLinkage()) + return SectionKind::getCommon(); + // Variable can be easily put to BSS section. - if (isSuitableForBSS(GVar)) + if (isSuitableForBSS(GVar)) { + if (GVar->hasLocalLinkage()) + return SectionKind::getBSSLocal(); + else if (GVar->hasExternalLinkage()) + return SectionKind::getBSSExtern(); return SectionKind::getBSS(); + } + + const Constant *C = GVar->getInitializer(); - 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()) { @@ -150,12 +160,18 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, // 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"); + default: assert(0 && "unknown relocation info kind"); case Constant::NoRelocation: + // If the global is required to have a unique address, it can't be put + // into a mergable section: just drop it into the general read-only + // section instead. + if (!GVar->hasUnnamedAddr()) + return SectionKind::getReadOnly(); + // If initializer is a null-terminated string, put it in a "cstring" // section of the right width. - if (const ArrayType *ATy = dyn_cast(C->getType())) { - if (const IntegerType *ITy = + if (ArrayType *ATy = dyn_cast(C->getType())) { + if (IntegerType *ITy = dyn_cast(ATy->getElementType())) { if ((ITy->getBitWidth() == 8 || ITy->getBitWidth() == 16 || ITy->getBitWidth() == 32) && @@ -164,13 +180,13 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, 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. @@ -180,7 +196,7 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, 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 @@ -189,11 +205,11 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, // 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 @@ -202,7 +218,7 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, // 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(); @@ -218,7 +234,7 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, return SectionKind::getDataNoRel(); switch (C->getRelocationInfo()) { - default: llvm_unreachable("unknown relocation info kind"); + default: assert(0 && "unknown relocation info kind"); case Constant::NoRelocation: return SectionKind::getDataNoRel(); case Constant::LocalRelocation: @@ -237,8 +253,8 @@ SectionForGlobal(const GlobalValue *GV, SectionKind Kind, Mangler *Mang, // 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); } @@ -251,13 +267,13 @@ TargetLoweringObjectFile::SelectSectionForGlobal(const GlobalValue *GV, 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; @@ -271,775 +287,39 @@ const MCSection * TargetLoweringObjectFile::getSectionForConstant(SectionKind Kind) const { if (Kind.isReadOnly() && ReadOnlySection != 0) return ReadOnlySection; - - return DataSection; -} - - - -//===----------------------------------------------------------------------===// -// ELF -//===----------------------------------------------------------------------===// -typedef StringMap 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 (strncmp(Name, ".gnu.linkonce.b.", 16) == 0 || - strncmp(Name, ".llvm.linkonce.b.", 17) == 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(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 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.append(Segment.begin(), Segment.end()); - Name.push_back(','); - Name.append(Section.begin(), Section.end()); - - // Do the lookup, if we have a hit, return it. - const MCSectionMachO *&Entry = Map[StringRef(Name.data(), Name.size())]; - 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(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 +/// getExprForDwarfGlobalReference - Return an MCExpr to use for a +/// reference to the specified global variable from exception +/// handling information. +const MCExpr *TargetLoweringObjectFile:: +getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang, + MachineModuleInfo *MMI, unsigned Encoding, + MCStreamer &Streamer) const { + const MCSymbol *Sym = Mang->getSymbol(GV); + return getExprForDwarfReference(Sym, Encoding, Streamer); } -/// 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(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; +const MCExpr *TargetLoweringObjectFile:: +getExprForDwarfReference(const MCSymbol *Sym, unsigned Encoding, + MCStreamer &Streamer) const { + const MCExpr *Res = MCSymbolRefExpr::Create(Sym, getContext()); + + switch (Encoding & 0x70) { + default: + report_fatal_error("We do not support this DWARF encoding yet!"); + case dwarf::DW_EH_PE_absptr: + // Do nothing special + return Res; + case dwarf::DW_EH_PE_pcrel: { + // Emit a label to the streamer for the current position. This gives us + // .-foo addressing. + MCSymbol *PCSym = getContext().CreateTempSymbol(); + Streamer.EmitLabel(PCSym); + const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, getContext()); + return MCBinaryExpr::CreateSub(Res, PC, getContext()); } - - return true; -} - - -//===----------------------------------------------------------------------===// -// COFF -//===----------------------------------------------------------------------===// - -typedef StringMap 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(); } -