freebsd-dev/include/llvm/MC/MCSymbol.h
2009-10-14 17:57:32 +00:00

119 lines
3.6 KiB
C++

//===- MCSymbol.h - Machine Code Symbols ------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of the MCSymbol class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCSYMBOL_H
#define LLVM_MC_MCSYMBOL_H
#include <string>
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/DataTypes.h"
namespace llvm {
class MCAsmInfo;
class MCSection;
class MCContext;
class raw_ostream;
/// MCSymbol - Instances of this class represent a symbol name in the MC file,
/// and MCSymbols are created and unique'd by the MCContext class.
///
/// If the symbol is defined/emitted into the current translation unit, the
/// Section member is set to indicate what section it lives in. Otherwise, if
/// it is a reference to an external entity, it has a null section.
///
class MCSymbol {
// Special sentinal value for the absolute pseudo section.
//
// FIXME: Use a PointerInt wrapper for this?
static const MCSection *AbsolutePseudoSection;
/// Name - The name of the symbol.
std::string Name;
/// Section - The section the symbol is defined in. This is null for
/// undefined symbols, and the special AbsolutePseudoSection value for
/// absolute symbols.
const MCSection *Section;
/// IsTemporary - True if this is an assembler temporary label, which
/// typically does not survive in the .o file's symbol table. Usually
/// "Lfoo" or ".foo".
unsigned IsTemporary : 1;
private: // MCContext creates and uniques these.
friend class MCContext;
MCSymbol(const StringRef &_Name, bool _IsTemporary)
: Name(_Name), Section(0), IsTemporary(_IsTemporary) {}
MCSymbol(const MCSymbol&); // DO NOT IMPLEMENT
void operator=(const MCSymbol&); // DO NOT IMPLEMENT
public:
/// getName - Get the symbol name.
const std::string &getName() const { return Name; }
/// @name Symbol Type
/// @{
/// isTemporary - Check if this is an assembler temporary symbol.
bool isTemporary() const {
return IsTemporary;
}
/// isDefined - Check if this symbol is defined (i.e., it has an address).
///
/// Defined symbols are either absolute or in some section.
bool isDefined() const {
return Section != 0;
}
/// isUndefined - Check if this symbol undefined (i.e., implicitly defined).
bool isUndefined() const {
return !isDefined();
}
/// isAbsolute - Check if this this is an absolute symbol.
bool isAbsolute() const {
return Section == AbsolutePseudoSection;
}
/// getSection - Get the section associated with a defined, non-absolute
/// symbol.
const MCSection &getSection() const {
assert(!isUndefined() && !isAbsolute() && "Invalid accessor!");
return *Section;
}
/// setSection - Mark the symbol as defined in the section \arg S.
void setSection(const MCSection &S) { Section = &S; }
/// setUndefined - Mark the symbol as undefined.
void setUndefined() {
Section = 0;
}
/// setAbsolute - Mark the symbol as absolute.
void setAbsolute() { Section = AbsolutePseudoSection; }
/// @}
/// print - Print the value to the stream \arg OS.
void print(raw_ostream &OS, const MCAsmInfo *MAI) const;
/// dump - Print the value to stderr.
void dump() const;
};
} // end namespace llvm
#endif