llvm-6502/include/llvm/GlobalVariable.h

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//===-- llvm/Global.h - Class to represent a global variable -----*- C++ -*--=//
//
// This file contains the declaration of the GlobalVariable class, which
// represents a single global variable (or constant) in the VM.
//
// Global variables are constant pointers that refer to hunks of space that are
// allocated by either the VM, or by the linker in a static compiler. A global
// variable may have an intial value, which is copied into the executables .data
// area. Global Constants are required to have initializers.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_GLOBAL_VARIABLE_H
#define LLVM_GLOBAL_VARIABLE_H
#include "llvm/GlobalValue.h"
class Module;
class Constant;
class PointerType;
class GlobalVariable : public GlobalValue {
friend class ValueHolder<GlobalVariable, Module, Module>;
void setParent(Module *parent) { Parent = parent; }
bool isConstantGlobal; // Is this a global constant?
public:
GlobalVariable(const Type *Ty, bool isConstant, bool isInternal,
Constant *Initializer = 0, const std::string &Name = "");
~GlobalVariable() {}
// Specialize setName to handle symbol table majik...
virtual void setName(const std::string &name, SymbolTable *ST = 0);
// The initializer for the global variable/constant is held by Operands[0] if
// an initializer is specified.
//
inline bool hasInitializer() const { return !Operands.empty(); }
inline Constant *getInitializer() const {
assert(hasInitializer() && "GV doesn't have initializer!");
return (Constant*)Operands[0].get();
}
inline Constant *getInitializer() {
assert(hasInitializer() && "GV doesn't have initializer!");
return (Constant*)Operands[0].get();
}
inline void setInitializer(Constant *CPV) {
if (CPV == 0) {
if (hasInitializer()) Operands.pop_back();
} else {
if (!hasInitializer()) Operands.push_back(Use(0, this));
Operands[0] = (Value*)CPV;
}
}
// If the value is a global constant, its value is immutable throughout the
// runtime execution of the program. Assigning a value into the constant
// leads to undefined behavior.
//
inline bool isConstant() const { return isConstantGlobal; }
virtual void print(std::ostream &OS) const;
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const GlobalVariable *) { return true; }
static inline bool classof(const Value *V) {
return V->getValueType() == Value::GlobalVariableVal;
}
};
#endif