llvm-6502/include/llvm/Constants.h
2007-07-16 14:29:03 +00:00

714 lines
29 KiB
C++

//===-- llvm/Constants.h - Constant class subclass definitions --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// @file This file contains the declarations for the subclasses of Constant,
/// which represent the different flavors of constant values that live in LLVM.
/// Note that Constants are immutable (once created they never change) and are
/// fully shared by structural equivalence. This means that two structurally
/// equivalent constants will always have the same address. Constant's are
/// created on demand as needed and never deleted: thus clients don't have to
/// worry about the lifetime of the objects.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CONSTANTS_H
#define LLVM_CONSTANTS_H
#include "llvm/Constant.h"
#include "llvm/Type.h"
#include "llvm/ADT/APInt.h"
namespace llvm {
class ArrayType;
class StructType;
class PointerType;
class VectorType;
template<class ConstantClass, class TypeClass, class ValType>
struct ConstantCreator;
template<class ConstantClass, class TypeClass>
struct ConvertConstantType;
//===----------------------------------------------------------------------===//
/// This is the shared class of boolean and integer constants. This class
/// represents both boolean and integral constants.
/// @brief Class for constant integers.
class ConstantInt : public Constant {
static ConstantInt *TheTrueVal, *TheFalseVal;
ConstantInt(const ConstantInt &); // DO NOT IMPLEMENT
ConstantInt(const IntegerType *Ty, const APInt& V);
APInt Val;
public:
/// Return the constant as an APInt value reference. This allows clients to
/// obtain a copy of the value, with all its precision in tact.
/// @brief Return the constant's value.
inline const APInt& getValue() const {
return Val;
}
/// getBitWidth - Return the bitwidth of this constant.
unsigned getBitWidth() const { return Val.getBitWidth(); }
/// Return the constant as a 64-bit unsigned integer value after it
/// has been zero extended as appropriate for the type of this constant. Note
/// that this method can assert if the value does not fit in 64 bits.
/// @deprecated
/// @brief Return the zero extended value.
inline uint64_t getZExtValue() const {
return Val.getZExtValue();
}
/// Return the constant as a 64-bit integer value after it has been sign
/// sign extended as appropriate for the type of this constant. Note that
/// this method can assert if the value does not fit in 64 bits.
/// @deprecated
/// @brief Return the sign extended value.
inline int64_t getSExtValue() const {
return Val.getSExtValue();
}
/// A helper method that can be used to determine if the constant contained
/// within is equal to a constant. This only works for very small values,
/// because this is all that can be represented with all types.
/// @brief Determine if this constant's value is same as an unsigned char.
bool equalsInt(uint64_t V) const {
return Val == V;
}
/// getTrue/getFalse - Return the singleton true/false values.
static inline ConstantInt *getTrue() {
if (TheTrueVal) return TheTrueVal;
return CreateTrueFalseVals(true);
}
static inline ConstantInt *getFalse() {
if (TheFalseVal) return TheFalseVal;
return CreateTrueFalseVals(false);
}
/// Return a ConstantInt with the specified value for the specified type. The
/// value V will be canonicalized to a an unsigned APInt. Accessing it with
/// either getSExtValue() or getZExtValue() will yield a correctly sized and
/// signed value for the type Ty.
/// @brief Get a ConstantInt for a specific value.
static ConstantInt *get(const Type *Ty, uint64_t V, bool isSigned = false);
/// Return a ConstantInt with the specified value and an implied Type. The
/// type is the integer type that corresponds to the bit width of the value.
static ConstantInt *get(const APInt &V);
/// getType - Specialize the getType() method to always return an IntegerType,
/// which reduces the amount of casting needed in parts of the compiler.
///
inline const IntegerType *getType() const {
return reinterpret_cast<const IntegerType*>(Value::getType());
}
/// This static method returns true if the type Ty is big enough to
/// represent the value V. This can be used to avoid having the get method
/// assert when V is larger than Ty can represent. Note that there are two
/// versions of this method, one for unsigned and one for signed integers.
/// Although ConstantInt canonicalizes everything to an unsigned integer,
/// the signed version avoids callers having to convert a signed quantity
/// to the appropriate unsigned type before calling the method.
/// @returns true if V is a valid value for type Ty
/// @brief Determine if the value is in range for the given type.
static bool isValueValidForType(const Type *Ty, uint64_t V);
static bool isValueValidForType(const Type *Ty, int64_t V);
/// This function will return true iff this constant represents the "null"
/// value that would be returned by the getNullValue method.
/// @returns true if this is the null integer value.
/// @brief Determine if the value is null.
virtual bool isNullValue() const {
return Val == 0;
}
/// This is just a convenience method to make client code smaller for a
/// common code. It also correctly performs the comparison without the
/// potential for an assertion from getZExtValue().
bool isZero() const {
return Val == 0;
}
/// This is just a convenience method to make client code smaller for a
/// common case. It also correctly performs the comparison without the
/// potential for an assertion from getZExtValue().
/// @brief Determine if the value is one.
bool isOne() const {
return Val == 1;
}
/// This function will return true iff every bit in this constant is set
/// to true.
/// @returns true iff this constant's bits are all set to true.
/// @brief Determine if the value is all ones.
bool isAllOnesValue() const {
return Val.isAllOnesValue();
}
/// This function will return true iff this constant represents the largest
/// value that may be represented by the constant's type.
/// @returns true iff this is the largest value that may be represented
/// by this type.
/// @brief Determine if the value is maximal.
bool isMaxValue(bool isSigned) const {
if (isSigned)
return Val.isMaxSignedValue();
else
return Val.isMaxValue();
}
/// This function will return true iff this constant represents the smallest
/// value that may be represented by this constant's type.
/// @returns true if this is the smallest value that may be represented by
/// this type.
/// @brief Determine if the value is minimal.
bool isMinValue(bool isSigned) const {
if (isSigned)
return Val.isMinSignedValue();
else
return Val.isMinValue();
}
/// This function will return true iff this constant represents a value with
/// active bits bigger than 64 bits or a value greater than the given uint64_t
/// value.
/// @returns true iff this constant is greater or equal to the given number.
/// @brief Determine if the value is greater or equal to the given number.
bool uge(uint64_t Num) {
return Val.getActiveBits() > 64 || Val.getZExtValue() >= Num;
}
/// @returns the 64-bit value of this constant if its active bits number is
/// not greater than 64, otherwise, just return the given uint64_t number.
/// @brief Get the constant's value if possible.
uint64_t getLimitedValue(uint64_t Limit = ~0ULL) const {
return Val.getLimitedValue(Limit);
}
/// @returns the value for an integer constant of the given type that has all
/// its bits set to true.
/// @brief Get the all ones value
static ConstantInt *getAllOnesValue(const Type *Ty);
/// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
static inline bool classof(const ConstantInt *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantIntVal;
}
static void ResetTrueFalse() { TheTrueVal = TheFalseVal = 0; }
private:
static ConstantInt *CreateTrueFalseVals(bool WhichOne);
};
//===----------------------------------------------------------------------===//
/// ConstantFP - Floating Point Values [float, double]
///
class ConstantFP : public Constant {
double Val;
ConstantFP(const ConstantFP &); // DO NOT IMPLEMENT
protected:
ConstantFP(const Type *Ty, double V);
public:
/// get() - Static factory methods - Return objects of the specified value
static ConstantFP *get(const Type *Ty, double V);
/// isValueValidForType - return true if Ty is big enough to represent V.
static bool isValueValidForType(const Type *Ty, double V);
inline double getValue() const { return Val; }
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue. Don't depend on == for doubles to tell us it's zero, it
/// considers -0.0 to be null as well as 0.0. :(
virtual bool isNullValue() const;
/// isExactlyValue - We don't rely on operator== working on double values, as
/// it returns true for things that are clearly not equal, like -0.0 and 0.0.
/// As such, this method can be used to do an exact bit-for-bit comparison of
/// two floating point values.
bool isExactlyValue(double V) const;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantFP *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantFPVal;
}
};
//===----------------------------------------------------------------------===//
/// ConstantAggregateZero - All zero aggregate value
///
class ConstantAggregateZero : public Constant {
friend struct ConstantCreator<ConstantAggregateZero, Type, char>;
ConstantAggregateZero(const ConstantAggregateZero &); // DO NOT IMPLEMENT
protected:
explicit ConstantAggregateZero(const Type *Ty)
: Constant(Ty, ConstantAggregateZeroVal, 0, 0) {}
public:
/// get() - static factory method for creating a null aggregate. It is
/// illegal to call this method with a non-aggregate type.
static Constant *get(const Type *Ty);
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue.
virtual bool isNullValue() const { return true; }
virtual void destroyConstant();
/// Methods for support type inquiry through isa, cast, and dyn_cast:
///
static bool classof(const ConstantAggregateZero *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantAggregateZeroVal;
}
};
//===----------------------------------------------------------------------===//
/// ConstantArray - Constant Array Declarations
///
class ConstantArray : public Constant {
friend struct ConstantCreator<ConstantArray, ArrayType,
std::vector<Constant*> >;
ConstantArray(const ConstantArray &); // DO NOT IMPLEMENT
protected:
ConstantArray(const ArrayType *T, const std::vector<Constant*> &Val);
~ConstantArray();
public:
/// get() - Static factory methods - Return objects of the specified value
static Constant *get(const ArrayType *T, const std::vector<Constant*> &);
static Constant *get(const ArrayType *T,
Constant*const*Vals, unsigned NumVals) {
// FIXME: make this the primary ctor method.
return get(T, std::vector<Constant*>(Vals, Vals+NumVals));
}
/// This method constructs a ConstantArray and initializes it with a text
/// string. The default behavior (AddNull==true) causes a null terminator to
/// be placed at the end of the array. This effectively increases the length
/// of the array by one (you've been warned). However, in some situations
/// this is not desired so if AddNull==false then the string is copied without
/// null termination.
static Constant *get(const std::string &Initializer, bool AddNull = true);
/// getType - Specialize the getType() method to always return an ArrayType,
/// which reduces the amount of casting needed in parts of the compiler.
///
inline const ArrayType *getType() const {
return reinterpret_cast<const ArrayType*>(Value::getType());
}
/// isString - This method returns true if the array is an array of sbyte or
/// ubyte, and if the elements of the array are all ConstantInt's.
bool isString() const;
/// isCString - This method returns true if the array is a string (see
/// isString) and it ends in a null byte \0 and does not contains any other
/// null bytes except its terminator.
bool isCString() const;
/// getAsString - If this array is isString(), then this method converts the
/// array to an std::string and returns it. Otherwise, it asserts out.
///
std::string getAsString() const;
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue. This always returns false because zero arrays are always
/// created as ConstantAggregateZero objects.
virtual bool isNullValue() const { return false; }
virtual void destroyConstant();
virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantArray *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantArrayVal;
}
};
//===----------------------------------------------------------------------===//
// ConstantStruct - Constant Struct Declarations
//
class ConstantStruct : public Constant {
friend struct ConstantCreator<ConstantStruct, StructType,
std::vector<Constant*> >;
ConstantStruct(const ConstantStruct &); // DO NOT IMPLEMENT
protected:
ConstantStruct(const StructType *T, const std::vector<Constant*> &Val);
~ConstantStruct();
public:
/// get() - Static factory methods - Return objects of the specified value
///
static Constant *get(const StructType *T, const std::vector<Constant*> &V);
static Constant *get(const std::vector<Constant*> &V, bool Packed = false);
static Constant *get(Constant*const* Vals, unsigned NumVals,
bool Packed = false) {
// FIXME: make this the primary ctor method.
return get(std::vector<Constant*>(Vals, Vals+NumVals), Packed);
}
/// getType() specialization - Reduce amount of casting...
///
inline const StructType *getType() const {
return reinterpret_cast<const StructType*>(Value::getType());
}
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue. This always returns false because zero structs are always
/// created as ConstantAggregateZero objects.
virtual bool isNullValue() const {
return false;
}
virtual void destroyConstant();
virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantStruct *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantStructVal;
}
};
//===----------------------------------------------------------------------===//
/// ConstantVector - Constant Vector Declarations
///
class ConstantVector : public Constant {
friend struct ConstantCreator<ConstantVector, VectorType,
std::vector<Constant*> >;
ConstantVector(const ConstantVector &); // DO NOT IMPLEMENT
protected:
ConstantVector(const VectorType *T, const std::vector<Constant*> &Val);
~ConstantVector();
public:
/// get() - Static factory methods - Return objects of the specified value
static Constant *get(const VectorType *T, const std::vector<Constant*> &);
static Constant *get(const std::vector<Constant*> &V);
static Constant *get(Constant*const* Vals, unsigned NumVals) {
// FIXME: make this the primary ctor method.
return get(std::vector<Constant*>(Vals, Vals+NumVals));
}
/// getType - Specialize the getType() method to always return a VectorType,
/// which reduces the amount of casting needed in parts of the compiler.
///
inline const VectorType *getType() const {
return reinterpret_cast<const VectorType*>(Value::getType());
}
/// @returns the value for a vector integer constant of the given type that
/// has all its bits set to true.
/// @brief Get the all ones value
static ConstantVector *getAllOnesValue(const VectorType *Ty);
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue. This always returns false because zero vectors are always
/// created as ConstantAggregateZero objects.
virtual bool isNullValue() const { return false; }
/// This function will return true iff every element in this vector constant
/// is set to all ones.
/// @returns true iff this constant's emements are all set to all ones.
/// @brief Determine if the value is all ones.
bool isAllOnesValue() const;
virtual void destroyConstant();
virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantVector *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantVectorVal;
}
};
//===----------------------------------------------------------------------===//
/// ConstantPointerNull - a constant pointer value that points to null
///
class ConstantPointerNull : public Constant {
friend struct ConstantCreator<ConstantPointerNull, PointerType, char>;
ConstantPointerNull(const ConstantPointerNull &); // DO NOT IMPLEMENT
protected:
explicit ConstantPointerNull(const PointerType *T)
: Constant(reinterpret_cast<const Type*>(T),
Value::ConstantPointerNullVal, 0, 0) {}
public:
/// get() - Static factory methods - Return objects of the specified value
static ConstantPointerNull *get(const PointerType *T);
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue.
virtual bool isNullValue() const { return true; }
virtual void destroyConstant();
/// getType - Specialize the getType() method to always return an PointerType,
/// which reduces the amount of casting needed in parts of the compiler.
///
inline const PointerType *getType() const {
return reinterpret_cast<const PointerType*>(Value::getType());
}
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantPointerNull *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == ConstantPointerNullVal;
}
};
/// ConstantExpr - a constant value that is initialized with an expression using
/// other constant values.
///
/// This class uses the standard Instruction opcodes to define the various
/// constant expressions. The Opcode field for the ConstantExpr class is
/// maintained in the Value::SubclassData field.
class ConstantExpr : public Constant {
friend struct ConstantCreator<ConstantExpr,Type,
std::pair<unsigned, std::vector<Constant*> > >;
friend struct ConvertConstantType<ConstantExpr, Type>;
protected:
ConstantExpr(const Type *Ty, unsigned Opcode, Use *Ops, unsigned NumOps)
: Constant(Ty, ConstantExprVal, Ops, NumOps) {
// Operation type (an Instruction opcode) is stored as the SubclassData.
SubclassData = Opcode;
}
// These private methods are used by the type resolution code to create
// ConstantExprs in intermediate forms.
static Constant *getTy(const Type *Ty, unsigned Opcode,
Constant *C1, Constant *C2);
static Constant *getCompareTy(unsigned short pred, Constant *C1,
Constant *C2);
static Constant *getSelectTy(const Type *Ty,
Constant *C1, Constant *C2, Constant *C3);
static Constant *getGetElementPtrTy(const Type *Ty, Constant *C,
Value* const *Idxs, unsigned NumIdxs);
static Constant *getExtractElementTy(const Type *Ty, Constant *Val,
Constant *Idx);
static Constant *getInsertElementTy(const Type *Ty, Constant *Val,
Constant *Elt, Constant *Idx);
static Constant *getShuffleVectorTy(const Type *Ty, Constant *V1,
Constant *V2, Constant *Mask);
public:
// Static methods to construct a ConstantExpr of different kinds. Note that
// these methods may return a object that is not an instance of the
// ConstantExpr class, because they will attempt to fold the constant
// expression into something simpler if possible.
/// Cast constant expr
///
static Constant *getTrunc (Constant *C, const Type *Ty);
static Constant *getSExt (Constant *C, const Type *Ty);
static Constant *getZExt (Constant *C, const Type *Ty);
static Constant *getFPTrunc (Constant *C, const Type *Ty);
static Constant *getFPExtend(Constant *C, const Type *Ty);
static Constant *getUIToFP (Constant *C, const Type *Ty);
static Constant *getSIToFP (Constant *C, const Type *Ty);
static Constant *getFPToUI (Constant *C, const Type *Ty);
static Constant *getFPToSI (Constant *C, const Type *Ty);
static Constant *getPtrToInt(Constant *C, const Type *Ty);
static Constant *getIntToPtr(Constant *C, const Type *Ty);
static Constant *getBitCast (Constant *C, const Type *Ty);
// @brief Convenience function for getting one of the casting operations
// using a CastOps opcode.
static Constant *getCast(
unsigned ops, ///< The opcode for the conversion
Constant *C, ///< The constant to be converted
const Type *Ty ///< The type to which the constant is converted
);
// @brief Create a ZExt or BitCast cast constant expression
static Constant *getZExtOrBitCast(
Constant *C, ///< The constant to zext or bitcast
const Type *Ty ///< The type to zext or bitcast C to
);
// @brief Create a SExt or BitCast cast constant expression
static Constant *getSExtOrBitCast(
Constant *C, ///< The constant to sext or bitcast
const Type *Ty ///< The type to sext or bitcast C to
);
// @brief Create a Trunc or BitCast cast constant expression
static Constant *getTruncOrBitCast(
Constant *C, ///< The constant to trunc or bitcast
const Type *Ty ///< The type to trunc or bitcast C to
);
/// @brief Create a BitCast or a PtrToInt cast constant expression
static Constant *getPointerCast(
Constant *C, ///< The pointer value to be casted (operand 0)
const Type *Ty ///< The type to which cast should be made
);
/// @brief Create a ZExt, Bitcast or Trunc for integer -> integer casts
static Constant *getIntegerCast(
Constant *C, ///< The integer constant to be casted
const Type *Ty, ///< The integer type to cast to
bool isSigned ///< Whether C should be treated as signed or not
);
/// @brief Create a FPExt, Bitcast or FPTrunc for fp -> fp casts
static Constant *getFPCast(
Constant *C, ///< The integer constant to be casted
const Type *Ty ///< The integer type to cast to
);
/// @brief Return true if this is a convert constant expression
bool isCast() const;
/// @brief Return true if this is a compare constant expression
bool isCompare() const;
/// Select constant expr
///
static Constant *getSelect(Constant *C, Constant *V1, Constant *V2) {
return getSelectTy(V1->getType(), C, V1, V2);
}
/// getSizeOf constant expr - computes the size of a type in a target
/// independent way (Note: the return type is a ULong).
///
static Constant *getSizeOf(const Type *Ty);
/// ConstantExpr::get - Return a binary or shift operator constant expression,
/// folding if possible.
///
static Constant *get(unsigned Opcode, Constant *C1, Constant *C2);
/// @brief Return an ICmp or FCmp comparison operator constant expression.
static Constant *getCompare(unsigned short pred, Constant *C1, Constant *C2);
/// ConstantExpr::get* - Return some common constants without having to
/// specify the full Instruction::OPCODE identifier.
///
static Constant *getNeg(Constant *C);
static Constant *getNot(Constant *C);
static Constant *getAdd(Constant *C1, Constant *C2);
static Constant *getSub(Constant *C1, Constant *C2);
static Constant *getMul(Constant *C1, Constant *C2);
static Constant *getUDiv(Constant *C1, Constant *C2);
static Constant *getSDiv(Constant *C1, Constant *C2);
static Constant *getFDiv(Constant *C1, Constant *C2);
static Constant *getURem(Constant *C1, Constant *C2); // unsigned rem
static Constant *getSRem(Constant *C1, Constant *C2); // signed rem
static Constant *getFRem(Constant *C1, Constant *C2);
static Constant *getAnd(Constant *C1, Constant *C2);
static Constant *getOr(Constant *C1, Constant *C2);
static Constant *getXor(Constant *C1, Constant *C2);
static Constant* getICmp(unsigned short pred, Constant* LHS, Constant* RHS);
static Constant* getFCmp(unsigned short pred, Constant* LHS, Constant* RHS);
static Constant *getShl(Constant *C1, Constant *C2);
static Constant *getLShr(Constant *C1, Constant *C2);
static Constant *getAShr(Constant *C1, Constant *C2);
/// Getelementptr form. std::vector<Value*> is only accepted for convenience:
/// all elements must be Constant's.
///
static Constant *getGetElementPtr(Constant *C,
Constant* const *IdxList, unsigned NumIdx);
static Constant *getGetElementPtr(Constant *C,
Value* const *IdxList, unsigned NumIdx);
static Constant *getExtractElement(Constant *Vec, Constant *Idx);
static Constant *getInsertElement(Constant *Vec, Constant *Elt,Constant *Idx);
static Constant *getShuffleVector(Constant *V1, Constant *V2, Constant *Mask);
/// Floating point negation must be implemented with f(x) = -0.0 - x. This
/// method returns the negative zero constant for floating point or vector
/// floating point types; for all other types, it returns the null value.
static Constant *getZeroValueForNegationExpr(const Type *Ty);
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue.
virtual bool isNullValue() const { return false; }
/// getOpcode - Return the opcode at the root of this constant expression
unsigned getOpcode() const { return SubclassData; }
/// getPredicate - Return the ICMP or FCMP predicate value. Assert if this is
/// not an ICMP or FCMP constant expression.
unsigned getPredicate() const;
/// getOpcodeName - Return a string representation for an opcode.
const char *getOpcodeName() const;
/// getWithOperandReplaced - Return a constant expression identical to this
/// one, but with the specified operand set to the specified value.
Constant *getWithOperandReplaced(unsigned OpNo, Constant *Op) const;
/// getWithOperands - This returns the current constant expression with the
/// operands replaced with the specified values. The specified operands must
/// match count and type with the existing ones.
Constant *getWithOperands(const std::vector<Constant*> &Ops) const;
virtual void destroyConstant();
virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
/// Override methods to provide more type information...
inline Constant *getOperand(unsigned i) {
return cast<Constant>(User::getOperand(i));
}
inline Constant *getOperand(unsigned i) const {
return const_cast<Constant*>(cast<Constant>(User::getOperand(i)));
}
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantExpr *) { return true; }
static inline bool classof(const Value *V) {
return V->getValueID() == ConstantExprVal;
}
};
//===----------------------------------------------------------------------===//
/// UndefValue - 'undef' values are things that do not have specified contents.
/// These are used for a variety of purposes, including global variable
/// initializers and operands to instructions. 'undef' values can occur with
/// any type.
///
class UndefValue : public Constant {
friend struct ConstantCreator<UndefValue, Type, char>;
UndefValue(const UndefValue &); // DO NOT IMPLEMENT
protected:
explicit UndefValue(const Type *T) : Constant(T, UndefValueVal, 0, 0) {}
public:
/// get() - Static factory methods - Return an 'undef' object of the specified
/// type.
///
static UndefValue *get(const Type *T);
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue.
virtual bool isNullValue() const { return false; }
virtual void destroyConstant();
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const UndefValue *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == UndefValueVal;
}
};
} // End llvm namespace
#endif