llvm-6502/include/llvm/Value.h
Chris Lattner e02cb164b1 Add a new slew of functions to allow dynamic_cast<> like operation for
upcasting Value's to their subclasses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80 91177308-0d34-0410-b5e6-96231b3b80d8
2001-06-27 23:27:42 +00:00

183 lines
6.6 KiB
C++

//===-- llvm/Value.h - Definition of the Value class -------------*- C++ -*--=//
//
// This file defines the very important Value class. This is subclassed by a
// bunch of other important classes, like Def, Method, Module, Type, etc...
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_VALUE_H
#define LLVM_VALUE_H
#include <string>
#include <list>
class User;
class Type;
class ConstPoolVal;
class MethodArgument;
class Instruction;
class BasicBlock;
class Method;
class Module;
template<class ValueSubclass, class ItemParentType> class ValueHolder;
//===----------------------------------------------------------------------===//
// Value Class
//===----------------------------------------------------------------------===//
class Value {
public:
enum ValueTy {
TypeVal, // This is an instance of Type
ConstantVal, // This is an instance of ConstPoolVal
MethodArgumentVal, // This is an instance of MethodArgument
InstructionVal, // This is an instance of Instruction
BasicBlockVal, // This is an instance of BasicBlock
MethodVal, // This is an instance of Method
ModuleVal, // This is an instance of Module
};
private:
list<User *> Uses;
string Name;
const Type *Ty;
ValueTy VTy;
Value(const Value &); // Do not implement
protected:
inline void setType(const Type *ty) { Ty = ty; }
public:
Value(const Type *Ty, ValueTy vty, const string &name = "");
virtual ~Value();
inline const Type *getType() const { return Ty; }
// All values can potentially be named...
inline bool hasName() const { return Name != ""; }
inline const string &getName() const { return Name; }
virtual void setName(const string &name) { Name = name; }
// Methods for determining the subtype of this Value. The getValueType()
// method returns the type of the value directly. The cast*() methods are
// equilivent to using dynamic_cast<>... if the cast is successful, this is
// returned, otherwise you get a null pointer, allowing expressions like this:
//
// if (Instruction *I = Val->castInstruction()) { ... }
//
// This section also defines a family of isType, isConstant, isMethodArgument,
// etc functions...
//
// The family of functions Val->cast<type>Asserting() is used in the same
// way as the Val->cast<type>() instructions, but they assert the expected
// type instead of checking it at runtime.
//
inline ValueTy getValueType() const { return VTy; }
// Use a macro to define the functions, otherwise these definitions are just
// really long and ugly.
#define CAST_FN(NAME, CLASS) \
inline bool is##NAME() const { return VTy == NAME##Val; } \
inline const CLASS *cast##NAME() const { /*const version */ \
return is##NAME() ? (const CLASS*)this : 0; \
} \
inline CLASS *cast##NAME() { /* nonconst version */ \
return is##NAME() ? (CLASS*)this : 0; \
} \
inline const CLASS *cast##NAME##Asserting() const { /*const version */ \
assert(is##NAME() && "Expected Value Type: " #NAME); \
return (const CLASS*)this; \
} \
inline CLASS *cast##NAME##Asserting() { /* nonconst version */ \
assert(is##NAME() && "Expected Value Type: " #NAME); \
return (CLASS*)this; \
} \
CAST_FN(Constant , ConstPoolVal )
CAST_FN(MethodArgument, MethodArgument)
CAST_FN(Instruction , Instruction )
CAST_FN(BasicBlock , BasicBlock )
CAST_FN(Method , Method )
CAST_FN(Module , Module )
#undef CAST_FN
// Type value is special, because there is no nonconst version of functions!
inline bool isType() const { return VTy == TypeVal; }
inline const Type *castType() const {
return (VTy == TypeVal) ? (const Type*)this : 0;
}
inline const Type *castTypeAsserting() const {
assert(isType() && "Expected Value Type: Type");
return (const Type*)this;
}
// replaceAllUsesWith - Go through the uses list for this definition and make
// each use point to "D" instead of "this". After this completes, 'this's
// use list should be empty.
//
void replaceAllUsesWith(Value *D);
//----------------------------------------------------------------------
// Methods for handling the list of uses of this DEF.
//
typedef list<User*>::iterator use_iterator;
typedef list<User*>::const_iterator use_const_iterator;
inline unsigned use_size() const { return Uses.size(); }
inline bool use_empty() const { return Uses.empty(); }
inline use_iterator use_begin() { return Uses.begin(); }
inline use_const_iterator use_begin() const { return Uses.begin(); }
inline use_iterator use_end() { return Uses.end(); }
inline use_const_iterator use_end() const { return Uses.end(); }
inline void use_push_back(User *I) { Uses.push_back(I); }
User *use_remove(use_iterator &I);
inline void addUse(User *I) { Uses.push_back(I); }
void killUse(User *I);
};
// UseTy and it's friendly typedefs (Use) are here to make keeping the "use"
// list of a definition node up-to-date really easy.
//
template<class ValueSubclass>
class UseTy {
ValueSubclass *Val;
User *U;
public:
inline UseTy<ValueSubclass>(ValueSubclass *v, User *user) {
Val = v; U = user;
if (Val) Val->addUse(U);
}
inline ~UseTy<ValueSubclass>() { if (Val) Val->killUse(U); }
inline operator ValueSubclass *() const { return Val; }
inline UseTy<ValueSubclass>(const UseTy<ValueSubclass> &user) {
Val = 0;
U = user.U;
operator=(user.Val);
}
inline ValueSubclass *operator=(ValueSubclass *V) {
if (Val) Val->killUse(U);
Val = V;
if (V) V->addUse(U);
return V;
}
inline ValueSubclass *operator->() { return Val; }
inline const ValueSubclass *operator->() const { return Val; }
inline UseTy<ValueSubclass> &operator=(const UseTy<ValueSubclass> &user) {
if (Val) Val->killUse(U);
Val = user.Val;
Val->addUse(U);
return *this;
}
};
typedef UseTy<Value> Use;
#endif