#ifndef LLVM_MC_MCSYMBOL_H
#define LLVM_MC_MCSYMBOL_H
-#include <string>
#include "llvm/ADT/StringRef.h"
-#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/Compiler.h"
namespace llvm {
+ class MCExpr;
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.
+ /// and MCSymbols are created and unique'd by the MCContext class. MCSymbols
+ /// should only be constructed with valid names for the object file.
///
/// 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.
- ///
+ /// 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;
+ /// Name - The name of the symbol. The referred-to string data is actually
+ /// held by the StringMap that lives in MCContext.
+ StringRef 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;
+ /// Value - If non-null, the value for a variable symbol.
+ const MCExpr *Value;
+
/// 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;
+ /// IsUsed - True if this symbol has been used.
+ mutable unsigned IsUsed : 1;
+
private: // MCContext creates and uniques these.
+ friend class MCExpr;
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
+ MCSymbol(StringRef name, bool isTemporary)
+ : Name(name), Section(nullptr), Value(nullptr),
+ IsTemporary(isTemporary), IsUsed(false) {}
+
+ MCSymbol(const MCSymbol&) LLVM_DELETED_FUNCTION;
+ void operator=(const MCSymbol&) LLVM_DELETED_FUNCTION;
public:
/// getName - Get the symbol name.
- const std::string &getName() const { return Name; }
+ StringRef getName() const { return Name; }
- /// @name Symbol Type
+ /// @name Accessors
/// @{
/// isTemporary - Check if this is an assembler temporary symbol.
- bool isTemporary() const {
- return IsTemporary;
- }
+ bool isTemporary() const { return IsTemporary; }
+
+ /// isUsed - Check if this is used.
+ bool isUsed() const { return IsUsed; }
+ void setUsed(bool Value) const { IsUsed = Value; }
+
+ /// @}
+ /// @name Associated Sections
+ /// @{
/// 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;
+ return Section != nullptr;
+ }
+
+ /// isInSection - Check if this symbol is defined in some section (i.e., it
+ /// is defined but not absolute).
+ bool isInSection() const {
+ return isDefined() && !isAbsolute();
}
/// isUndefined - Check if this symbol undefined (i.e., implicitly defined).
return !isDefined();
}
- /// isAbsolute - Check if this this is an absolute symbol.
+ /// isAbsolute - Check if 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!");
+ assert(isInSection() && "Invalid accessor!");
return *Section;
}
- /// setSection - Mark the symbol as defined in the section \arg S.
+ /// setSection - Mark the symbol as defined in the section \p S.
void setSection(const MCSection &S) { Section = &S; }
/// setUndefined - Mark the symbol as undefined.
void setUndefined() {
- Section = 0;
+ Section = nullptr;
}
/// setAbsolute - Mark the symbol as absolute.
void setAbsolute() { Section = AbsolutePseudoSection; }
+ /// @}
+ /// @name Variable Symbols
+ /// @{
+
+ /// isVariable - Check if this is a variable symbol.
+ bool isVariable() const {
+ return Value != nullptr;
+ }
+
+ /// getVariableValue() - Get the value for variable symbols.
+ const MCExpr *getVariableValue() const {
+ assert(isVariable() && "Invalid accessor!");
+ IsUsed = true;
+ return Value;
+ }
+
+ // AliasedSymbol() - If this is an alias (a = b), return the symbol
+ // we ultimately point to. For a non-alias, this just returns the symbol
+ // itself.
+ const MCSymbol &AliasedSymbol() const;
+
+ void setVariableValue(const MCExpr *Value);
+
/// @}
- /// print - Print the value to the stream \arg OS.
+ /// print - Print the value to the stream \p OS.
void print(raw_ostream &OS) const;
/// dump - Print the value to stderr.
void dump() const;
};
+ inline raw_ostream &operator<<(raw_ostream &OS, const MCSymbol &Sym) {
+ Sym.print(OS);
+ return OS;
+ }
} // end namespace llvm
#endif