llvm-6502/lib/MC/MCContext.cpp
Jan Wen Voung 186e7a0fb1 Move logic of determining ELF entsize from the .s printer to initialization
time. That way, the EntrySize field is initialized for other code paths, 
namely, the .ll -> .o code path.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115141 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-30 05:59:22 +00:00

270 lines
9.7 KiB
C++

//===- 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/ADT/SmallString.h"
#include "llvm/ADT/Twine.h"
using namespace llvm;
typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
typedef StringMap<const MCSectionELF*> ELFUniqueMapTy;
typedef StringMap<const MCSectionCOFF*> COFFUniqueMapTy;
MCContext::MCContext(const MCAsmInfo &mai) : MAI(mai), NextUniqueID(0),
CurrentDwarfLoc(0,0,0,0,0) {
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;
}
//===----------------------------------------------------------------------===//
// Symbol Manipulation
//===----------------------------------------------------------------------===//
MCSymbol *MCContext::GetOrCreateSymbol(StringRef Name) {
assert(!Name.empty() && "Normal symbols cannot be unnamed!");
// Determine whether this is an assembler temporary or normal label.
bool isTemporary = Name.startswith(MAI.getPrivateGlobalPrefix());
// 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);
if (Entry.getValue()) return Entry.getValue();
// Ok, the entry doesn't already exist. Have the MCSymbol object itself refer
// to the copy of the string that is embedded in the StringMapEntry.
MCSymbol *Result = new (*this) MCSymbol(Entry.getKey(), isTemporary);
Entry.setValue(Result);
return Result;
}
MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name) {
SmallString<128> NameSV;
Name.toVector(NameSV);
return GetOrCreateSymbol(NameSV.str());
}
MCSymbol *MCContext::CreateTempSymbol() {
return GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix()) +
"tmp" + Twine(NextUniqueID++));
}
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 MCSection *MCContext::
getELFSection(StringRef Section, unsigned Type, unsigned Flags,
SectionKind Kind, bool IsExplicit, unsigned EntrySize) {
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);
}
MCSectionELF *Result = new (*this) MCSectionELF(Entry.getKey(), Type, Flags,
Kind, IsExplicit, EntrySize);
Entry.setValue(Result);
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;
}
/// ValidateDwarfFileNumber - takes a dwarf file number and returns true if it
/// currently is assigned and false otherwise.
bool MCContext::ValidateDwarfFileNumber(unsigned FileNumber) {
if(FileNumber == 0 || FileNumber >= MCDwarfFiles.size())
return false;
MCDwarfFile *&ExistingFile = MCDwarfFiles[FileNumber];
if (ExistingFile)
return true;
else
return false;
}