llvm-6502/include/llvm/Type.h
2003-10-09 20:43:55 +00:00

315 lines
12 KiB
C++

//===-- llvm/Type.h - Classes for handling data types -----------*- C++ -*-===//
//
// This file contains the declaration of the Type class. For more "Type" type
// stuff, look in DerivedTypes.h.
//
// Note that instances of the Type class are immutable: once they are created,
// they are never changed. Also note that only one instance of a particular
// type is ever created. Thus seeing if two types are equal is a matter of
// doing a trivial pointer comparison.
//
// Types, once allocated, are never free'd.
//
// Opaque types are simple derived types with no state. There may be many
// different Opaque type objects floating around, but two are only considered
// identical if they are pointer equals of each other. This allows us to have
// two opaque types that end up resolving to different concrete types later.
//
// Opaque types are also kinda wierd and scary and different because they have
// to keep a list of uses of the type. When, through linking, parsing, or
// bytecode reading, they become resolved, they need to find and update all
// users of the unknown type, causing them to reference a new, more concrete
// type. Opaque types are deleted when their use list dwindles to zero users.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TYPE_H
#define LLVM_TYPE_H
#include "llvm/Value.h"
#include "Support/GraphTraits.h"
#include "Support/iterator"
class DerivedType;
class FunctionType;
class ArrayType;
class PointerType;
class StructType;
class OpaqueType;
struct Type : public Value {
///===-------------------------------------------------------------------===//
/// Definitions of all of the base types for the Type system. Based on this
/// value, you can cast to a "DerivedType" subclass (see DerivedTypes.h)
/// Note: If you add an element to this, you need to add an element to the
/// Type::getPrimitiveType function, or else things will break!
///
enum PrimitiveID {
VoidTyID = 0 , BoolTyID, // 0, 1: Basics...
UByteTyID , SByteTyID, // 2, 3: 8 bit types...
UShortTyID , ShortTyID, // 4, 5: 16 bit types...
UIntTyID , IntTyID, // 6, 7: 32 bit types...
ULongTyID , LongTyID, // 8, 9: 64 bit types...
FloatTyID , DoubleTyID, // 10,11: Floating point types...
TypeTyID, // 12 : Type definitions
LabelTyID , // 13 : Labels...
// Derived types... see DerivedTypes.h file...
// Make sure FirstDerivedTyID stays up to date!!!
FunctionTyID , StructTyID, // Functions... Structs...
ArrayTyID , PointerTyID, // Array... pointer...
OpaqueTyID, // Opaque type instances...
//PackedTyID , // SIMD 'packed' format... TODO
//...
NumPrimitiveIDs, // Must remain as last defined ID
FirstDerivedTyID = FunctionTyID,
};
private:
PrimitiveID ID; // The current base type of this type...
unsigned UID; // The unique ID number for this class
bool Abstract; // True if type contains an OpaqueType
const Type *getForwardedTypeInternal() const;
protected:
/// ctor is protected, so only subclasses can create Type objects...
Type(const std::string &Name, PrimitiveID id);
virtual ~Type() {}
/// setName - Associate the name with this type in the symbol table, but don't
/// set the local name to be equal specified name.
///
virtual void setName(const std::string &Name, SymbolTable *ST = 0);
/// Types can become nonabstract later, if they are refined.
///
inline void setAbstract(bool Val) { Abstract = Val; }
/// isTypeAbstract - This method is used to calculate the Abstract bit.
///
bool isTypeAbstract();
/// ForwardType - This field is used to implement the union find scheme for
/// abstract types. When types are refined to other types, this field is set
/// to the more refined type. Only abstract types can be forwarded.
mutable const Type *ForwardType;
public:
virtual void print(std::ostream &O) const;
//===--------------------------------------------------------------------===//
// Property accessors for dealing with types... Some of these virtual methods
// are defined in private classes defined in Type.cpp for primitive types.
//
/// getPrimitiveID - Return the base type of the type. This will return one
/// of the PrimitiveID enum elements defined above.
///
inline PrimitiveID getPrimitiveID() const { return ID; }
/// getUniqueID - Returns the UID of the type. This can be thought of as a
/// small integer version of the pointer to the type class. Two types that
/// are structurally different have different UIDs. This can be used for
/// indexing types into an array.
///
inline unsigned getUniqueID() const { return UID; }
/// getDescription - Return the string representation of the type...
const std::string &getDescription() const;
/// isSigned - Return whether an integral numeric type is signed. This is
/// true for SByteTy, ShortTy, IntTy, LongTy. Note that this is not true for
/// Float and Double.
//
virtual bool isSigned() const { return 0; }
/// isUnsigned - Return whether a numeric type is unsigned. This is not quite
/// the complement of isSigned... nonnumeric types return false as they do
/// with isSigned. This returns true for UByteTy, UShortTy, UIntTy, and
/// ULongTy
///
virtual bool isUnsigned() const { return 0; }
/// isInteger - Equilivent to isSigned() || isUnsigned(), but with only a
/// single virtual function invocation.
///
virtual bool isInteger() const { return 0; }
/// isIntegral - Returns true if this is an integral type, which is either
/// BoolTy or one of the Integer types.
///
bool isIntegral() const { return isInteger() || this == BoolTy; }
/// isFloatingPoint - Return true if this is one of the two floating point
/// types
bool isFloatingPoint() const { return ID == FloatTyID || ID == DoubleTyID; }
/// isAbstract - True if the type is either an Opaque type, or is a derived
/// type that includes an opaque type somewhere in it.
///
inline bool isAbstract() const { return Abstract; }
/// isLosslesslyConvertibleTo - Return true if this type can be converted to
/// 'Ty' without any reinterpretation of bits. For example, uint to int.
///
bool isLosslesslyConvertibleTo(const Type *Ty) const;
/// Here are some useful little methods to query what type derived types are
/// Note that all other types can just compare to see if this == Type::xxxTy;
///
inline bool isPrimitiveType() const { return ID < FirstDerivedTyID; }
inline bool isDerivedType() const { return ID >= FirstDerivedTyID; }
/// isFirstClassType - Return true if the value is holdable in a register.
inline bool isFirstClassType() const {
return isPrimitiveType() || ID == PointerTyID;
}
/// isSized - Return true if it makes sense to take the size of this type. To
/// get the actual size for a particular target, it is reasonable to use the
/// TargetData subsystem to do this.
///
bool isSized() const {
return ID != VoidTyID && ID != TypeTyID &&
ID != FunctionTyID && ID != LabelTyID && ID != OpaqueTyID;
}
/// getPrimitiveSize - Return the basic size of this type if it is a primative
/// type. These are fixed by LLVM and are not target dependent. This will
/// return zero if the type does not have a size or is not a primitive type.
///
unsigned getPrimitiveSize() const;
/// getForwaredType - Return the type that this type has been resolved to if
/// it has been resolved to anything. This is used to implement the
/// union-find algorithm for type resolution.
const Type *getForwardedType() const {
if (!ForwardType) return 0;
return getForwardedTypeInternal();
}
//===--------------------------------------------------------------------===//
// Type Iteration support
//
class TypeIterator;
typedef TypeIterator subtype_iterator;
inline subtype_iterator subtype_begin() const; // DEFINED BELOW
inline subtype_iterator subtype_end() const; // DEFINED BELOW
/// getContainedType - This method is used to implement the type iterator
/// (defined a the end of the file). For derived types, this returns the
/// types 'contained' in the derived type.
///
virtual const Type *getContainedType(unsigned i) const {
assert(0 && "No contained types!");
return 0;
}
/// getNumContainedTypes - Return the number of types in the derived type
virtual unsigned getNumContainedTypes() const { return 0; }
//===--------------------------------------------------------------------===//
// Static members exported by the Type class itself. Useful for getting
// instances of Type.
//
/// getPrimitiveType/getUniqueIDType - Return a type based on an identifier.
static const Type *getPrimitiveType(PrimitiveID IDNumber);
static const Type *getUniqueIDType(unsigned UID);
//===--------------------------------------------------------------------===//
// These are the builtin types that are always available...
//
static Type *VoidTy , *BoolTy;
static Type *SByteTy, *UByteTy,
*ShortTy, *UShortTy,
*IntTy , *UIntTy,
*LongTy , *ULongTy;
static Type *FloatTy, *DoubleTy;
static Type *TypeTy , *LabelTy;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Type *T) { return true; }
static inline bool classof(const Value *V) {
return V->getValueType() == Value::TypeVal;
}
#include "llvm/Type.def"
private:
class TypeIterator : public bidirectional_iterator<const Type, ptrdiff_t> {
const Type * const Ty;
unsigned Idx;
typedef TypeIterator _Self;
public:
inline TypeIterator(const Type *ty, unsigned idx) : Ty(ty), Idx(idx) {}
inline ~TypeIterator() {}
inline bool operator==(const _Self& x) const { return Idx == x.Idx; }
inline bool operator!=(const _Self& x) const { return !operator==(x); }
inline pointer operator*() const { return Ty->getContainedType(Idx); }
inline pointer operator->() const { return operator*(); }
inline _Self& operator++() { ++Idx; return *this; } // Preincrement
inline _Self operator++(int) { // Postincrement
_Self tmp = *this; ++*this; return tmp;
}
inline _Self& operator--() { --Idx; return *this; } // Predecrement
inline _Self operator--(int) { // Postdecrement
_Self tmp = *this; --*this; return tmp;
}
};
};
inline Type::TypeIterator Type::subtype_begin() const {
return TypeIterator(this, 0);
}
inline Type::TypeIterator Type::subtype_end() const {
return TypeIterator(this, getNumContainedTypes());
}
// Provide specializations of GraphTraits to be able to treat a type as a
// graph of sub types...
template <> struct GraphTraits<Type*> {
typedef Type NodeType;
typedef Type::subtype_iterator ChildIteratorType;
static inline NodeType *getEntryNode(Type *T) { return T; }
static inline ChildIteratorType child_begin(NodeType *N) {
return N->subtype_begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->subtype_end();
}
};
template <> struct GraphTraits<const Type*> {
typedef const Type NodeType;
typedef Type::subtype_iterator ChildIteratorType;
static inline NodeType *getEntryNode(const Type *T) { return T; }
static inline ChildIteratorType child_begin(NodeType *N) {
return N->subtype_begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->subtype_end();
}
};
template <> inline bool isa_impl<PointerType, Type>(const Type &Ty) {
return Ty.getPrimitiveID() == Type::PointerTyID;
}
#endif