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Diffstat (limited to 'contrib/llvm/lib/MC/MCContext.cpp')
-rw-r--r-- | contrib/llvm/lib/MC/MCContext.cpp | 312 |
1 files changed, 312 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..018f00c --- /dev/null +++ b/contrib/llvm/lib/MC/MCContext.cpp @@ -0,0 +1,312 @@ +//===- 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/MC/MCAsmInfo.h" +#include "llvm/MC/MCSectionMachO.h" +#include "llvm/MC/MCSectionELF.h" +#include "llvm/MC/MCSectionCOFF.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MCLabel.h" +#include "llvm/MC/MCDwarf.h" +#include "llvm/Target/TargetAsmInfo.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/Twine.h" +#include "llvm/Support/ELF.h" +using namespace llvm; + +typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy; +typedef StringMap<const MCSectionELF*> ELFUniqueMapTy; +typedef StringMap<const MCSectionCOFF*> COFFUniqueMapTy; + + +MCContext::MCContext(const MCAsmInfo &mai, const TargetAsmInfo *tai) : + MAI(mai), TAI(tai), NextUniqueID(0), + CurrentDwarfLoc(0,0,0,DWARF2_FLAG_IS_STMT,0,0) { + MachOUniquingMap = 0; + ELFUniquingMap = 0; + COFFUniquingMap = 0; + + SecureLogFile = getenv("AS_SECURE_LOG_FILE"); + SecureLog = 0; + SecureLogUsed = false; + + DwarfLocSeen = false; +} + +MCContext::~MCContext() { + // NOTE: The symbols are all allocated out of a bump pointer allocator, + // we don't need to free them here. + + // If we have the MachO uniquing map, free it. + delete (MachOUniqueMapTy*)MachOUniquingMap; + delete (ELFUniqueMapTy*)ELFUniquingMap; + delete (COFFUniqueMapTy*)COFFUniquingMap; + + // If the stream for the .secure_log_unique directive was created free it. + delete (raw_ostream*)SecureLog; + + delete TAI; +} + +//===----------------------------------------------------------------------===// +// Symbol Manipulation +//===----------------------------------------------------------------------===// + +MCSymbol *MCContext::GetOrCreateSymbol(StringRef Name) { + assert(!Name.empty() && "Normal symbols cannot be unnamed!"); + + // Do the lookup and get the entire StringMapEntry. We want access to the + // key if we are creating the entry. + StringMapEntry<MCSymbol*> &Entry = Symbols.GetOrCreateValue(Name); + MCSymbol *Sym = Entry.getValue(); + + if (Sym) + return Sym; + + Sym = CreateSymbol(Name); + Entry.setValue(Sym); + return Sym; +} + +MCSymbol *MCContext::CreateSymbol(StringRef Name) { + // Determine whether this is an assembler temporary or normal label. + bool isTemporary = Name.startswith(MAI.getPrivateGlobalPrefix()); + + StringMapEntry<bool> *NameEntry = &UsedNames.GetOrCreateValue(Name); + if (NameEntry->getValue()) { + assert(isTemporary && "Cannot rename non temporary symbols"); + SmallString<128> NewName; + do { + Twine T = Name + Twine(NextUniqueID++); + T.toVector(NewName); + StringRef foo = NewName; + NameEntry = &UsedNames.GetOrCreateValue(foo); + } while (NameEntry->getValue()); + } + NameEntry->setValue(true); + + // Ok, the entry doesn't already exist. Have the MCSymbol object itself refer + // to the copy of the string that is embedded in the UsedNames entry. + MCSymbol *Result = new (*this) MCSymbol(NameEntry->getKey(), isTemporary); + + return Result; +} + +MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name) { + SmallString<128> NameSV; + Name.toVector(NameSV); + return GetOrCreateSymbol(NameSV.str()); +} + +MCSymbol *MCContext::CreateTempSymbol() { + SmallString<128> NameSV; + Twine Name = Twine(MAI.getPrivateGlobalPrefix()) + "tmp" + + Twine(NextUniqueID++); + Name.toVector(NameSV); + return CreateSymbol(NameSV); +} + +unsigned MCContext::NextInstance(int64_t LocalLabelVal) { + MCLabel *&Label = Instances[LocalLabelVal]; + if (!Label) + Label = new (*this) MCLabel(0); + return Label->incInstance(); +} + +unsigned MCContext::GetInstance(int64_t LocalLabelVal) { + MCLabel *&Label = Instances[LocalLabelVal]; + if (!Label) + Label = new (*this) MCLabel(0); + return Label->getInstance(); +} + +MCSymbol *MCContext::CreateDirectionalLocalSymbol(int64_t LocalLabelVal) { + return GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix()) + + Twine(LocalLabelVal) + + "\2" + + Twine(NextInstance(LocalLabelVal))); +} +MCSymbol *MCContext::GetDirectionalLocalSymbol(int64_t LocalLabelVal, + int bORf) { + return GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix()) + + Twine(LocalLabelVal) + + "\2" + + Twine(GetInstance(LocalLabelVal) + bORf)); +} + +MCSymbol *MCContext::LookupSymbol(StringRef Name) const { + return Symbols.lookup(Name); +} + +//===----------------------------------------------------------------------===// +// Section Management +//===----------------------------------------------------------------------===// + +const MCSectionMachO *MCContext:: +getMachOSection(StringRef Segment, StringRef Section, + unsigned TypeAndAttributes, + unsigned Reserved2, SectionKind Kind) { + + // 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 (MachOUniquingMap == 0) + MachOUniquingMap = new MachOUniqueMapTy(); + MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)MachOUniquingMap; + + // 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 = new (*this) MCSectionMachO(Segment, Section, TypeAndAttributes, + Reserved2, Kind); +} + +const MCSectionELF *MCContext:: +getELFSection(StringRef Section, unsigned Type, unsigned Flags, + SectionKind Kind) { + return getELFSection(Section, Type, Flags, Kind, 0, ""); +} + +const MCSectionELF *MCContext:: +getELFSection(StringRef Section, unsigned Type, unsigned Flags, + SectionKind Kind, unsigned EntrySize, StringRef Group) { + if (ELFUniquingMap == 0) + ELFUniquingMap = new ELFUniqueMapTy(); + ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)ELFUniquingMap; + + // Do the lookup, if we have a hit, return it. + StringMapEntry<const MCSectionELF*> &Entry = Map.GetOrCreateValue(Section); + if (Entry.getValue()) return Entry.getValue(); + + // Possibly refine the entry size first. + if (!EntrySize) { + EntrySize = MCSectionELF::DetermineEntrySize(Kind); + } + + MCSymbol *GroupSym = NULL; + if (!Group.empty()) + GroupSym = GetOrCreateSymbol(Group); + + MCSectionELF *Result = new (*this) MCSectionELF(Entry.getKey(), Type, Flags, + Kind, EntrySize, GroupSym); + Entry.setValue(Result); + return Result; +} + +const MCSectionELF *MCContext::CreateELFGroupSection() { + MCSectionELF *Result = + new (*this) MCSectionELF(".group", ELF::SHT_GROUP, 0, + SectionKind::getReadOnly(), 4, NULL); + return Result; +} + +const MCSection *MCContext::getCOFFSection(StringRef Section, + unsigned Characteristics, + int Selection, + SectionKind Kind) { + if (COFFUniquingMap == 0) + COFFUniquingMap = new COFFUniqueMapTy(); + COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap; + + // Do the lookup, if we have a hit, return it. + StringMapEntry<const MCSectionCOFF*> &Entry = Map.GetOrCreateValue(Section); + if (Entry.getValue()) return Entry.getValue(); + + MCSectionCOFF *Result = new (*this) MCSectionCOFF(Entry.getKey(), + Characteristics, + Selection, Kind); + + Entry.setValue(Result); + return Result; +} + +//===----------------------------------------------------------------------===// +// 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 FileName, unsigned FileNumber) { + // TODO: a FileNumber of zero says to use the next available file number. + // Note: in GenericAsmParser::ParseDirectiveFile() FileNumber was checked + // to not be less than one. This needs to be change to be not less than zero. + + // Make space for this FileNumber in the MCDwarfFiles vector if needed. + if (FileNumber >= MCDwarfFiles.size()) { + MCDwarfFiles.resize(FileNumber + 1); + } else { + MCDwarfFile *&ExistingFile = MCDwarfFiles[FileNumber]; + if (ExistingFile) + // It is an error to use see the same number more than once. + return 0; + } + + // Get the new MCDwarfFile slot for this FileNumber. + MCDwarfFile *&File = MCDwarfFiles[FileNumber]; + + // Separate the directory part from the basename of the FileName. + std::pair<StringRef, StringRef> Slash = FileName.rsplit('/'); + + // Find or make a entry in the MCDwarfDirs vector for this Directory. + StringRef Name; + unsigned DirIndex; + // Capture directory name. + if (Slash.second.empty()) { + Name = Slash.first; + DirIndex = 0; // For FileNames with no directories a DirIndex of 0 is used. + } else { + StringRef Directory = Slash.first; + Name = Slash.second; + for (DirIndex = 0; DirIndex < MCDwarfDirs.size(); DirIndex++) { + if (Directory == MCDwarfDirs[DirIndex]) + break; + } + if (DirIndex >= MCDwarfDirs.size()) { + char *Buf = static_cast<char *>(Allocate(Directory.size())); + memcpy(Buf, Directory.data(), Directory.size()); + MCDwarfDirs.push_back(StringRef(Buf, Directory.size())); + } + // The DirIndex is one based, as DirIndex of 0 is used for FileNames with + // no directories. MCDwarfDirs[] is unlike MCDwarfFiles[] in that the + // directory names are stored at MCDwarfDirs[DirIndex-1] where FileNames are + // stored at MCDwarfFiles[FileNumber].Name . + DirIndex++; + } + + // Now make the MCDwarfFile entry and place it in the slot in the MCDwarfFiles + // vector. + char *Buf = static_cast<char *>(Allocate(Name.size())); + memcpy(Buf, Name.data(), Name.size()); + File = new (*this) MCDwarfFile(StringRef(Buf, Name.size()), DirIndex); + + // return the allocated FileNumber. + return FileNumber; +} + +/// isValidDwarfFileNumber - takes a dwarf file number and returns true if it +/// currently is assigned and false otherwise. +bool MCContext::isValidDwarfFileNumber(unsigned FileNumber) { + if(FileNumber == 0 || FileNumber >= MCDwarfFiles.size()) + return false; + + return MCDwarfFiles[FileNumber] != 0; +} |