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Diffstat (limited to 'contrib/llvm/lib/MC/MCContext.cpp')
-rw-r--r-- | contrib/llvm/lib/MC/MCContext.cpp | 501 |
1 files changed, 501 insertions, 0 deletions
diff --git a/contrib/llvm/lib/MC/MCContext.cpp b/contrib/llvm/lib/MC/MCContext.cpp new file mode 100644 index 0000000..b5ad518 --- /dev/null +++ b/contrib/llvm/lib/MC/MCContext.cpp @@ -0,0 +1,501 @@ +//===- lib/MC/MCContext.cpp - Machine Code Context ------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/MC/MCContext.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/Twine.h" +#include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCDwarf.h" +#include "llvm/MC/MCLabel.h" +#include "llvm/MC/MCObjectFileInfo.h" +#include "llvm/MC/MCRegisterInfo.h" +#include "llvm/MC/MCSectionCOFF.h" +#include "llvm/MC/MCSectionELF.h" +#include "llvm/MC/MCSectionMachO.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSymbolCOFF.h" +#include "llvm/MC/MCSymbolELF.h" +#include "llvm/MC/MCSymbolMachO.h" +#include "llvm/Support/COFF.h" +#include "llvm/Support/ELF.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/Signals.h" +#include "llvm/Support/SourceMgr.h" +#include <map> + +using namespace llvm; + +MCContext::MCContext(const MCAsmInfo *mai, const MCRegisterInfo *mri, + const MCObjectFileInfo *mofi, const SourceMgr *mgr, + bool DoAutoReset) + : SrcMgr(mgr), MAI(mai), MRI(mri), MOFI(mofi), Allocator(), + Symbols(Allocator), UsedNames(Allocator), + CurrentDwarfLoc(0, 0, 0, DWARF2_FLAG_IS_STMT, 0, 0), DwarfLocSeen(false), + GenDwarfForAssembly(false), GenDwarfFileNumber(0), DwarfVersion(4), + AllowTemporaryLabels(true), DwarfCompileUnitID(0), + AutoReset(DoAutoReset), HadError(false) { + + std::error_code EC = llvm::sys::fs::current_path(CompilationDir); + if (EC) + CompilationDir.clear(); + + SecureLogFile = getenv("AS_SECURE_LOG_FILE"); + SecureLog = nullptr; + SecureLogUsed = false; + + if (SrcMgr && SrcMgr->getNumBuffers()) + MainFileName = + SrcMgr->getMemoryBuffer(SrcMgr->getMainFileID())->getBufferIdentifier(); +} + +MCContext::~MCContext() { + if (AutoReset) + reset(); + + // NOTE: The symbols are all allocated out of a bump pointer allocator, + // we don't need to free them here. +} + +//===----------------------------------------------------------------------===// +// Module Lifetime Management +//===----------------------------------------------------------------------===// + +void MCContext::reset() { + // Call the destructors so the fragments are freed + COFFAllocator.DestroyAll(); + ELFAllocator.DestroyAll(); + MachOAllocator.DestroyAll(); + + MCSubtargetAllocator.DestroyAll(); + UsedNames.clear(); + Symbols.clear(); + SectionSymbols.clear(); + Allocator.Reset(); + Instances.clear(); + CompilationDir.clear(); + MainFileName.clear(); + MCDwarfLineTablesCUMap.clear(); + SectionsForRanges.clear(); + MCGenDwarfLabelEntries.clear(); + DwarfDebugFlags = StringRef(); + DwarfCompileUnitID = 0; + CurrentDwarfLoc = MCDwarfLoc(0, 0, 0, DWARF2_FLAG_IS_STMT, 0, 0); + + MachOUniquingMap.clear(); + ELFUniquingMap.clear(); + COFFUniquingMap.clear(); + + NextID.clear(); + AllowTemporaryLabels = true; + DwarfLocSeen = false; + GenDwarfForAssembly = false; + GenDwarfFileNumber = 0; + + HadError = false; +} + +//===----------------------------------------------------------------------===// +// Symbol Manipulation +//===----------------------------------------------------------------------===// + +MCSymbol *MCContext::getOrCreateSymbol(const Twine &Name) { + SmallString<128> NameSV; + StringRef NameRef = Name.toStringRef(NameSV); + + assert(!NameRef.empty() && "Normal symbols cannot be unnamed!"); + + MCSymbol *&Sym = Symbols[NameRef]; + if (!Sym) + Sym = createSymbol(NameRef, false, false); + + return Sym; +} + +MCSymbolELF *MCContext::getOrCreateSectionSymbol(const MCSectionELF &Section) { + MCSymbolELF *&Sym = SectionSymbols[&Section]; + if (Sym) + return Sym; + + StringRef Name = Section.getSectionName(); + + MCSymbol *&OldSym = Symbols[Name]; + if (OldSym && OldSym->isUndefined()) { + Sym = cast<MCSymbolELF>(OldSym); + return Sym; + } + + auto NameIter = UsedNames.insert(std::make_pair(Name, true)).first; + Sym = new (&*NameIter, *this) MCSymbolELF(&*NameIter, /*isTemporary*/ false); + + if (!OldSym) + OldSym = Sym; + + return Sym; +} + +MCSymbol *MCContext::getOrCreateFrameAllocSymbol(StringRef FuncName, + unsigned Idx) { + return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + FuncName + + "$frame_escape_" + Twine(Idx)); +} + +MCSymbol *MCContext::getOrCreateParentFrameOffsetSymbol(StringRef FuncName) { + return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + FuncName + + "$parent_frame_offset"); +} + +MCSymbol *MCContext::getOrCreateLSDASymbol(StringRef FuncName) { + return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + "__ehtable$" + + FuncName); +} + +MCSymbol *MCContext::createSymbolImpl(const StringMapEntry<bool> *Name, + bool IsTemporary) { + if (MOFI) { + switch (MOFI->getObjectFileType()) { + case MCObjectFileInfo::IsCOFF: + return new (Name, *this) MCSymbolCOFF(Name, IsTemporary); + case MCObjectFileInfo::IsELF: + return new (Name, *this) MCSymbolELF(Name, IsTemporary); + case MCObjectFileInfo::IsMachO: + return new (Name, *this) MCSymbolMachO(Name, IsTemporary); + } + } + return new (Name, *this) MCSymbol(MCSymbol::SymbolKindUnset, Name, + IsTemporary); +} + +MCSymbol *MCContext::createSymbol(StringRef Name, bool AlwaysAddSuffix, + bool CanBeUnnamed) { + if (CanBeUnnamed && !UseNamesOnTempLabels) + return createSymbolImpl(nullptr, true); + + // Determine whether this is an user writter assembler temporary or normal + // label, if used. + bool IsTemporary = CanBeUnnamed; + if (AllowTemporaryLabels && !IsTemporary) + IsTemporary = Name.startswith(MAI->getPrivateGlobalPrefix()); + + SmallString<128> NewName = Name; + bool AddSuffix = AlwaysAddSuffix; + unsigned &NextUniqueID = NextID[Name]; + for (;;) { + if (AddSuffix) { + NewName.resize(Name.size()); + raw_svector_ostream(NewName) << NextUniqueID++; + } + auto NameEntry = UsedNames.insert(std::make_pair(NewName, true)); + if (NameEntry.second) { + // Ok, we found a name. Have the MCSymbol object itself refer to the copy + // of the string that is embedded in the UsedNames entry. + return createSymbolImpl(&*NameEntry.first, IsTemporary); + } + assert(IsTemporary && "Cannot rename non-temporary symbols"); + AddSuffix = true; + } + llvm_unreachable("Infinite loop"); +} + +MCSymbol *MCContext::createTempSymbol(const Twine &Name, bool AlwaysAddSuffix, + bool CanBeUnnamed) { + SmallString<128> NameSV; + raw_svector_ostream(NameSV) << MAI->getPrivateGlobalPrefix() << Name; + return createSymbol(NameSV, AlwaysAddSuffix, CanBeUnnamed); +} + +MCSymbol *MCContext::createLinkerPrivateTempSymbol() { + SmallString<128> NameSV; + raw_svector_ostream(NameSV) << MAI->getLinkerPrivateGlobalPrefix() << "tmp"; + return createSymbol(NameSV, true, false); +} + +MCSymbol *MCContext::createTempSymbol(bool CanBeUnnamed) { + return createTempSymbol("tmp", true, CanBeUnnamed); +} + +unsigned MCContext::NextInstance(unsigned LocalLabelVal) { + MCLabel *&Label = Instances[LocalLabelVal]; + if (!Label) + Label = new (*this) MCLabel(0); + return Label->incInstance(); +} + +unsigned MCContext::GetInstance(unsigned LocalLabelVal) { + MCLabel *&Label = Instances[LocalLabelVal]; + if (!Label) + Label = new (*this) MCLabel(0); + return Label->getInstance(); +} + +MCSymbol *MCContext::getOrCreateDirectionalLocalSymbol(unsigned LocalLabelVal, + unsigned Instance) { + MCSymbol *&Sym = LocalSymbols[std::make_pair(LocalLabelVal, Instance)]; + if (!Sym) + Sym = createTempSymbol(false); + return Sym; +} + +MCSymbol *MCContext::createDirectionalLocalSymbol(unsigned LocalLabelVal) { + unsigned Instance = NextInstance(LocalLabelVal); + return getOrCreateDirectionalLocalSymbol(LocalLabelVal, Instance); +} + +MCSymbol *MCContext::getDirectionalLocalSymbol(unsigned LocalLabelVal, + bool Before) { + unsigned Instance = GetInstance(LocalLabelVal); + if (!Before) + ++Instance; + return getOrCreateDirectionalLocalSymbol(LocalLabelVal, Instance); +} + +MCSymbol *MCContext::lookupSymbol(const Twine &Name) const { + SmallString<128> NameSV; + StringRef NameRef = Name.toStringRef(NameSV); + return Symbols.lookup(NameRef); +} + +//===----------------------------------------------------------------------===// +// Section Management +//===----------------------------------------------------------------------===// + +MCSectionMachO *MCContext::getMachOSection(StringRef Segment, StringRef Section, + unsigned TypeAndAttributes, + unsigned Reserved2, SectionKind Kind, + const char *BeginSymName) { + + // 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. + + // 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. + MCSectionMachO *&Entry = MachOUniquingMap[Name]; + if (Entry) + return Entry; + + MCSymbol *Begin = nullptr; + if (BeginSymName) + Begin = createTempSymbol(BeginSymName, false); + + // Otherwise, return a new section. + return Entry = new (MachOAllocator.Allocate()) MCSectionMachO( + Segment, Section, TypeAndAttributes, Reserved2, Kind, Begin); +} + +void MCContext::renameELFSection(MCSectionELF *Section, StringRef Name) { + StringRef GroupName; + if (const MCSymbol *Group = Section->getGroup()) + GroupName = Group->getName(); + + unsigned UniqueID = Section->getUniqueID(); + ELFUniquingMap.erase( + ELFSectionKey{Section->getSectionName(), GroupName, UniqueID}); + auto I = ELFUniquingMap.insert(std::make_pair( + ELFSectionKey{Name, GroupName, UniqueID}, + Section)) + .first; + StringRef CachedName = I->first.SectionName; + const_cast<MCSectionELF *>(Section)->setSectionName(CachedName); +} + +MCSectionELF *MCContext::createELFRelSection(StringRef Name, unsigned Type, + unsigned Flags, unsigned EntrySize, + const MCSymbolELF *Group, + const MCSectionELF *Associated) { + StringMap<bool>::iterator I; + bool Inserted; + std::tie(I, Inserted) = ELFRelSecNames.insert(std::make_pair(Name, true)); + + return new (ELFAllocator.Allocate()) + MCSectionELF(I->getKey(), Type, Flags, SectionKind::getReadOnly(), + EntrySize, Group, true, nullptr, Associated); +} + +MCSectionELF *MCContext::getELFSection(StringRef Section, unsigned Type, + unsigned Flags, unsigned EntrySize, + StringRef Group, unsigned UniqueID, + const char *BeginSymName) { + MCSymbolELF *GroupSym = nullptr; + if (!Group.empty()) + GroupSym = cast<MCSymbolELF>(getOrCreateSymbol(Group)); + + return getELFSection(Section, Type, Flags, EntrySize, GroupSym, UniqueID, + BeginSymName, nullptr); +} + +MCSectionELF *MCContext::getELFSection(StringRef Section, unsigned Type, + unsigned Flags, unsigned EntrySize, + const MCSymbolELF *GroupSym, + unsigned UniqueID, + const char *BeginSymName, + const MCSectionELF *Associated) { + StringRef Group = ""; + if (GroupSym) + Group = GroupSym->getName(); + // Do the lookup, if we have a hit, return it. + auto IterBool = ELFUniquingMap.insert( + std::make_pair(ELFSectionKey{Section, Group, UniqueID}, nullptr)); + auto &Entry = *IterBool.first; + if (!IterBool.second) + return Entry.second; + + StringRef CachedName = Entry.first.SectionName; + + SectionKind Kind; + if (Flags & ELF::SHF_EXECINSTR) + Kind = SectionKind::getText(); + else + Kind = SectionKind::getReadOnly(); + + MCSymbol *Begin = nullptr; + if (BeginSymName) + Begin = createTempSymbol(BeginSymName, false); + + MCSectionELF *Result = new (ELFAllocator.Allocate()) + MCSectionELF(CachedName, Type, Flags, Kind, EntrySize, GroupSym, UniqueID, + Begin, Associated); + Entry.second = Result; + return Result; +} + +MCSectionELF *MCContext::createELFGroupSection(const MCSymbolELF *Group) { + MCSectionELF *Result = new (ELFAllocator.Allocate()) + MCSectionELF(".group", ELF::SHT_GROUP, 0, SectionKind::getReadOnly(), 4, + Group, ~0, nullptr, nullptr); + return Result; +} + +MCSectionCOFF *MCContext::getCOFFSection(StringRef Section, + unsigned Characteristics, + SectionKind Kind, + StringRef COMDATSymName, int Selection, + const char *BeginSymName) { + MCSymbol *COMDATSymbol = nullptr; + if (!COMDATSymName.empty()) { + COMDATSymbol = getOrCreateSymbol(COMDATSymName); + COMDATSymName = COMDATSymbol->getName(); + } + + // Do the lookup, if we have a hit, return it. + COFFSectionKey T{Section, COMDATSymName, Selection}; + auto IterBool = COFFUniquingMap.insert(std::make_pair(T, nullptr)); + auto Iter = IterBool.first; + if (!IterBool.second) + return Iter->second; + + MCSymbol *Begin = nullptr; + if (BeginSymName) + Begin = createTempSymbol(BeginSymName, false); + + StringRef CachedName = Iter->first.SectionName; + MCSectionCOFF *Result = new (COFFAllocator.Allocate()) MCSectionCOFF( + CachedName, Characteristics, COMDATSymbol, Selection, Kind, Begin); + + Iter->second = Result; + return Result; +} + +MCSectionCOFF *MCContext::getCOFFSection(StringRef Section, + unsigned Characteristics, + SectionKind Kind, + const char *BeginSymName) { + return getCOFFSection(Section, Characteristics, Kind, "", 0, BeginSymName); +} + +MCSectionCOFF *MCContext::getCOFFSection(StringRef Section) { + COFFSectionKey T{Section, "", 0}; + auto Iter = COFFUniquingMap.find(T); + if (Iter == COFFUniquingMap.end()) + return nullptr; + return Iter->second; +} + +MCSectionCOFF *MCContext::getAssociativeCOFFSection(MCSectionCOFF *Sec, + const MCSymbol *KeySym) { + // Return the normal section if we don't have to be associative. + if (!KeySym) + return Sec; + + // Make an associative section with the same name and kind as the normal + // section. + unsigned Characteristics = + Sec->getCharacteristics() | COFF::IMAGE_SCN_LNK_COMDAT; + return getCOFFSection(Sec->getSectionName(), Characteristics, Sec->getKind(), + KeySym->getName(), + COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE); +} + +MCSubtargetInfo &MCContext::getSubtargetCopy(const MCSubtargetInfo &STI) { + return *new (MCSubtargetAllocator.Allocate()) MCSubtargetInfo(STI); +} + +//===----------------------------------------------------------------------===// +// Dwarf Management +//===----------------------------------------------------------------------===// + +/// getDwarfFile - takes a file name an number to place in the dwarf file and +/// directory tables. If the file number has already been allocated it is an +/// error and zero is returned and the client reports the error, else the +/// allocated file number is returned. The file numbers may be in any order. +unsigned MCContext::getDwarfFile(StringRef Directory, StringRef FileName, + unsigned FileNumber, unsigned CUID) { + MCDwarfLineTable &Table = MCDwarfLineTablesCUMap[CUID]; + return Table.getFile(Directory, FileName, FileNumber); +} + +/// isValidDwarfFileNumber - takes a dwarf file number and returns true if it +/// currently is assigned and false otherwise. +bool MCContext::isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID) { + const SmallVectorImpl<MCDwarfFile> &MCDwarfFiles = getMCDwarfFiles(CUID); + if (FileNumber == 0 || FileNumber >= MCDwarfFiles.size()) + return false; + + return !MCDwarfFiles[FileNumber].Name.empty(); +} + +/// Remove empty sections from SectionStartEndSyms, to avoid generating +/// useless debug info for them. +void MCContext::finalizeDwarfSections(MCStreamer &MCOS) { + SectionsForRanges.remove_if( + [&](MCSection *Sec) { return !MCOS.mayHaveInstructions(*Sec); }); +} + +//===----------------------------------------------------------------------===// +// Error Reporting +//===----------------------------------------------------------------------===// + +void MCContext::reportError(SMLoc Loc, const Twine &Msg) { + HadError = true; + + // If we have a source manager use it. Otherwise just use the generic + // report_fatal_error(). + if (!SrcMgr) + report_fatal_error(Msg, false); + + // Use the source manager to print the message. + SrcMgr->PrintMessage(Loc, SourceMgr::DK_Error, Msg); +} + +void MCContext::reportFatalError(SMLoc Loc, const Twine &Msg) { + reportError(Loc, Msg); + + // If we reached here, we are failing ungracefully. Run the interrupt handlers + // to make sure any special cleanups get done, in particular that we remove + // files registered with RemoveFileOnSignal. + sys::RunInterruptHandlers(); + exit(1); +} |