1 //===-- llvm/Constants.h - Constant class subclass definitions --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This file contains the declarations for the subclasses of Constant,
12 /// which represent the different flavors of constant values that live in LLVM.
13 /// Note that Constants are immutable (once created they never change) and are
14 /// fully shared by structural equivalence. This means that two structurally
15 /// equivalent constants will always have the same address. Constant's are
16 /// created on demand as needed and never deleted: thus clients don't have to
17 /// worry about the lifetime of the objects.
19 //===----------------------------------------------------------------------===//
21 #ifndef LLVM_CONSTANTS_H
22 #define LLVM_CONSTANTS_H
24 #include "llvm/Constant.h"
25 #include "llvm/Type.h"
26 #include "llvm/OperandTraits.h"
27 #include "llvm/ADT/APInt.h"
28 #include "llvm/ADT/APFloat.h"
29 #include "llvm/ADT/SmallVector.h"
38 template<class ConstantClass, class TypeClass, class ValType>
39 struct ConstantCreator;
40 template<class ConstantClass, class TypeClass>
41 struct ConvertConstantType;
43 //===----------------------------------------------------------------------===//
44 /// This is the shared class of boolean and integer constants. This class
45 /// represents both boolean and integral constants.
46 /// @brief Class for constant integers.
47 class ConstantInt : public Constant {
48 static ConstantInt *TheTrueVal, *TheFalseVal;
49 void *operator new(size_t, unsigned); // DO NOT IMPLEMENT
50 ConstantInt(const ConstantInt &); // DO NOT IMPLEMENT
51 ConstantInt(const IntegerType *Ty, const APInt& V);
54 // allocate space for exactly zero operands
55 void *operator new(size_t s) {
56 return User::operator new(s, 0);
59 /// If Ty is a vector type, return a Constant with a splat of the given
60 /// value. Otherwise return a ConstantInt for the given value.
61 static Constant* get(const Type* Ty, uint64_t V, bool isSigned = false);
63 /// Return a ConstantInt with the specified integer value for the specified
64 /// type. If the type is wider than 64 bits, the value will be zero-extended
65 /// to fit the type, unless isSigned is true, in which case the value will
66 /// be interpreted as a 64-bit signed integer and sign-extended to fit
68 /// @brief Get a ConstantInt for a specific value.
69 static ConstantInt* get(const IntegerType* Ty, uint64_t V,
70 bool isSigned = false);
72 /// Return a ConstantInt with the specified value for the specified type. The
73 /// value V will be canonicalized to a an unsigned APInt. Accessing it with
74 /// either getSExtValue() or getZExtValue() will yield a correctly sized and
75 /// signed value for the type Ty.
76 /// @brief Get a ConstantInt for a specific signed value.
77 static ConstantInt* getSigned(const IntegerType* Ty, int64_t V);
78 static Constant *getSigned(const Type *Ty, int64_t V);
80 /// Return a ConstantInt with the specified value and an implied Type. The
81 /// type is the integer type that corresponds to the bit width of the value.
82 static ConstantInt* get(LLVMContext &Context, const APInt& V);
84 /// If Ty is a vector type, return a Constant with a splat of the given
85 /// value. Otherwise return a ConstantInt for the given value.
86 static Constant* get(const Type* Ty, const APInt& V);
88 /// Return the constant as an APInt value reference. This allows clients to
89 /// obtain a copy of the value, with all its precision in tact.
90 /// @brief Return the constant's value.
91 inline const APInt& getValue() const {
95 /// getBitWidth - Return the bitwidth of this constant.
96 unsigned getBitWidth() const { return Val.getBitWidth(); }
98 /// Return the constant as a 64-bit unsigned integer value after it
99 /// has been zero extended as appropriate for the type of this constant. Note
100 /// that this method can assert if the value does not fit in 64 bits.
102 /// @brief Return the zero extended value.
103 inline uint64_t getZExtValue() const {
104 return Val.getZExtValue();
107 /// Return the constant as a 64-bit integer value after it has been sign
108 /// extended as appropriate for the type of this constant. Note that
109 /// this method can assert if the value does not fit in 64 bits.
111 /// @brief Return the sign extended value.
112 inline int64_t getSExtValue() const {
113 return Val.getSExtValue();
116 /// A helper method that can be used to determine if the constant contained
117 /// within is equal to a constant. This only works for very small values,
118 /// because this is all that can be represented with all types.
119 /// @brief Determine if this constant's value is same as an unsigned char.
120 bool equalsInt(uint64_t V) const {
124 /// getType - Specialize the getType() method to always return an IntegerType,
125 /// which reduces the amount of casting needed in parts of the compiler.
127 inline const IntegerType *getType() const {
128 return reinterpret_cast<const IntegerType*>(Value::getType());
131 /// This static method returns true if the type Ty is big enough to
132 /// represent the value V. This can be used to avoid having the get method
133 /// assert when V is larger than Ty can represent. Note that there are two
134 /// versions of this method, one for unsigned and one for signed integers.
135 /// Although ConstantInt canonicalizes everything to an unsigned integer,
136 /// the signed version avoids callers having to convert a signed quantity
137 /// to the appropriate unsigned type before calling the method.
138 /// @returns true if V is a valid value for type Ty
139 /// @brief Determine if the value is in range for the given type.
140 static bool isValueValidForType(const Type *Ty, uint64_t V);
141 static bool isValueValidForType(const Type *Ty, int64_t V);
143 /// This function will return true iff this constant represents the "null"
144 /// value that would be returned by the getNullValue method.
145 /// @returns true if this is the null integer value.
146 /// @brief Determine if the value is null.
147 virtual bool isNullValue() const {
151 /// This is just a convenience method to make client code smaller for a
152 /// common code. It also correctly performs the comparison without the
153 /// potential for an assertion from getZExtValue().
154 bool isZero() const {
158 /// This is just a convenience method to make client code smaller for a
159 /// common case. It also correctly performs the comparison without the
160 /// potential for an assertion from getZExtValue().
161 /// @brief Determine if the value is one.
166 /// This function will return true iff every bit in this constant is set
168 /// @returns true iff this constant's bits are all set to true.
169 /// @brief Determine if the value is all ones.
170 bool isAllOnesValue() const {
171 return Val.isAllOnesValue();
174 /// This function will return true iff this constant represents the largest
175 /// value that may be represented by the constant's type.
176 /// @returns true iff this is the largest value that may be represented
178 /// @brief Determine if the value is maximal.
179 bool isMaxValue(bool isSigned) const {
181 return Val.isMaxSignedValue();
183 return Val.isMaxValue();
186 /// This function will return true iff this constant represents the smallest
187 /// value that may be represented by this constant's type.
188 /// @returns true if this is the smallest value that may be represented by
190 /// @brief Determine if the value is minimal.
191 bool isMinValue(bool isSigned) const {
193 return Val.isMinSignedValue();
195 return Val.isMinValue();
198 /// This function will return true iff this constant represents a value with
199 /// active bits bigger than 64 bits or a value greater than the given uint64_t
201 /// @returns true iff this constant is greater or equal to the given number.
202 /// @brief Determine if the value is greater or equal to the given number.
203 bool uge(uint64_t Num) {
204 return Val.getActiveBits() > 64 || Val.getZExtValue() >= Num;
207 /// getLimitedValue - If the value is smaller than the specified limit,
208 /// return it, otherwise return the limit value. This causes the value
209 /// to saturate to the limit.
210 /// @returns the min of the value of the constant and the specified value
211 /// @brief Get the constant's value with a saturation limit
212 uint64_t getLimitedValue(uint64_t Limit = ~0ULL) const {
213 return Val.getLimitedValue(Limit);
216 /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
217 static inline bool classof(const ConstantInt *) { return true; }
218 static bool classof(const Value *V) {
219 return V->getValueID() == ConstantIntVal;
224 //===----------------------------------------------------------------------===//
225 /// ConstantFP - Floating Point Values [float, double]
227 class ConstantFP : public Constant {
229 void *operator new(size_t, unsigned);// DO NOT IMPLEMENT
230 ConstantFP(const ConstantFP &); // DO NOT IMPLEMENT
231 friend class LLVMContextImpl;
233 ConstantFP(const Type *Ty, const APFloat& V);
235 // allocate space for exactly zero operands
236 void *operator new(size_t s) {
237 return User::operator new(s, 0);
240 /// Floating point negation must be implemented with f(x) = -0.0 - x. This
241 /// method returns the negative zero constant for floating point or vector
242 /// floating point types; for all other types, it returns the null value.
243 static Constant* getZeroValueForNegation(const Type* Ty);
245 /// get() - This returns a ConstantFP, or a vector containing a splat of a
246 /// ConstantFP, for the specified value in the specified type. This should
247 /// only be used for simple constant values like 2.0/1.0 etc, that are
248 /// known-valid both as host double and as the target format.
249 static Constant* get(const Type* Ty, double V);
250 static ConstantFP* get(LLVMContext &Context, const APFloat& V);
251 static ConstantFP* getNegativeZero(const Type* Ty);
253 /// isValueValidForType - return true if Ty is big enough to represent V.
254 static bool isValueValidForType(const Type *Ty, const APFloat& V);
255 inline const APFloat& getValueAPF() const { return Val; }
257 /// isNullValue - Return true if this is the value that would be returned by
258 /// getNullValue. Don't depend on == for doubles to tell us it's zero, it
259 /// considers -0.0 to be null as well as 0.0. :(
260 virtual bool isNullValue() const;
262 /// isNegativeZeroValue - Return true if the value is what would be returned
263 /// by getZeroValueForNegation.
264 virtual bool isNegativeZeroValue() const {
265 return Val.isZero() && Val.isNegative();
268 /// isExactlyValue - We don't rely on operator== working on double values, as
269 /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
270 /// As such, this method can be used to do an exact bit-for-bit comparison of
271 /// two floating point values. The version with a double operand is retained
272 /// because it's so convenient to write isExactlyValue(2.0), but please use
273 /// it only for simple constants.
274 bool isExactlyValue(const APFloat& V) const;
276 bool isExactlyValue(double V) const {
278 // convert is not supported on this type
279 if (&Val.getSemantics() == &APFloat::PPCDoubleDouble)
282 FV.convert(Val.getSemantics(), APFloat::rmNearestTiesToEven, &ignored);
283 return isExactlyValue(FV);
285 /// Methods for support type inquiry through isa, cast, and dyn_cast:
286 static inline bool classof(const ConstantFP *) { return true; }
287 static bool classof(const Value *V) {
288 return V->getValueID() == ConstantFPVal;
292 //===----------------------------------------------------------------------===//
293 /// ConstantAggregateZero - All zero aggregate value
295 class ConstantAggregateZero : public Constant {
296 friend struct ConstantCreator<ConstantAggregateZero, Type, char>;
297 void *operator new(size_t, unsigned); // DO NOT IMPLEMENT
298 ConstantAggregateZero(const ConstantAggregateZero &); // DO NOT IMPLEMENT
300 explicit ConstantAggregateZero(const Type *ty)
301 : Constant(ty, ConstantAggregateZeroVal, 0, 0) {}
303 // allocate space for exactly zero operands
304 void *operator new(size_t s) {
305 return User::operator new(s, 0);
308 /// isNullValue - Return true if this is the value that would be returned by
310 virtual bool isNullValue() const { return true; }
312 virtual void destroyConstant();
314 /// Methods for support type inquiry through isa, cast, and dyn_cast:
316 static bool classof(const ConstantAggregateZero *) { return true; }
317 static bool classof(const Value *V) {
318 return V->getValueID() == ConstantAggregateZeroVal;
323 //===----------------------------------------------------------------------===//
324 /// ConstantArray - Constant Array Declarations
326 class ConstantArray : public Constant {
327 friend struct ConstantCreator<ConstantArray, ArrayType,
328 std::vector<Constant*> >;
329 ConstantArray(const ConstantArray &); // DO NOT IMPLEMENT
331 ConstantArray(const ArrayType *T, const std::vector<Constant*> &Val);
333 // ConstantArray accessors
334 static Constant* get(const ArrayType* T, const std::vector<Constant*>& V);
335 static Constant* get(const ArrayType* T, Constant* const* Vals,
338 /// This method constructs a ConstantArray and initializes it with a text
339 /// string. The default behavior (AddNull==true) causes a null terminator to
340 /// be placed at the end of the array. This effectively increases the length
341 /// of the array by one (you've been warned). However, in some situations
342 /// this is not desired so if AddNull==false then the string is copied without
343 /// null termination.
344 static Constant* get(const StringRef &Initializer, bool AddNull = true);
346 /// Transparently provide more efficient getOperand methods.
347 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
349 /// getType - Specialize the getType() method to always return an ArrayType,
350 /// which reduces the amount of casting needed in parts of the compiler.
352 inline const ArrayType *getType() const {
353 return reinterpret_cast<const ArrayType*>(Value::getType());
356 /// isString - This method returns true if the array is an array of i8 and
357 /// the elements of the array are all ConstantInt's.
358 bool isString() const;
360 /// isCString - This method returns true if the array is a string (see
362 /// isString) and it ends in a null byte \0 and does not contains any other
364 /// null bytes except its terminator.
365 bool isCString() const;
367 /// getAsString - If this array is isString(), then this method converts the
368 /// array to an std::string and returns it. Otherwise, it asserts out.
370 std::string getAsString() const;
372 /// isNullValue - Return true if this is the value that would be returned by
373 /// getNullValue. This always returns false because zero arrays are always
374 /// created as ConstantAggregateZero objects.
375 virtual bool isNullValue() const { return false; }
377 virtual void destroyConstant();
378 virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
380 /// Methods for support type inquiry through isa, cast, and dyn_cast:
381 static inline bool classof(const ConstantArray *) { return true; }
382 static bool classof(const Value *V) {
383 return V->getValueID() == ConstantArrayVal;
388 struct OperandTraits<ConstantArray> : VariadicOperandTraits<> {
391 DEFINE_TRANSPARENT_CASTED_OPERAND_ACCESSORS(ConstantArray, Constant)
393 //===----------------------------------------------------------------------===//
394 // ConstantStruct - Constant Struct Declarations
396 class ConstantStruct : public Constant {
397 friend struct ConstantCreator<ConstantStruct, StructType,
398 std::vector<Constant*> >;
399 ConstantStruct(const ConstantStruct &); // DO NOT IMPLEMENT
401 ConstantStruct(const StructType *T, const std::vector<Constant*> &Val);
403 // ConstantStruct accessors
404 static Constant* get(const StructType* T, const std::vector<Constant*>& V);
405 static Constant* get(const std::vector<Constant*>& V, bool Packed = false);
406 static Constant* get(Constant* const *Vals, unsigned NumVals,
407 bool Packed = false);
409 /// Transparently provide more efficient getOperand methods.
410 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
412 /// getType() specialization - Reduce amount of casting...
414 inline const StructType *getType() const {
415 return reinterpret_cast<const StructType*>(Value::getType());
418 /// isNullValue - Return true if this is the value that would be returned by
419 /// getNullValue. This always returns false because zero structs are always
420 /// created as ConstantAggregateZero objects.
421 virtual bool isNullValue() const {
425 virtual void destroyConstant();
426 virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
428 /// Methods for support type inquiry through isa, cast, and dyn_cast:
429 static inline bool classof(const ConstantStruct *) { return true; }
430 static bool classof(const Value *V) {
431 return V->getValueID() == ConstantStructVal;
436 struct OperandTraits<ConstantStruct> : VariadicOperandTraits<> {
439 DEFINE_TRANSPARENT_CASTED_OPERAND_ACCESSORS(ConstantStruct, Constant)
441 //===----------------------------------------------------------------------===//
442 /// ConstantVector - Constant Vector Declarations
444 class ConstantVector : public Constant {
445 friend struct ConstantCreator<ConstantVector, VectorType,
446 std::vector<Constant*> >;
447 ConstantVector(const ConstantVector &); // DO NOT IMPLEMENT
449 ConstantVector(const VectorType *T, const std::vector<Constant*> &Val);
451 /// Transparently provide more efficient getOperand methods.
452 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
454 /// getType - Specialize the getType() method to always return a VectorType,
455 /// which reduces the amount of casting needed in parts of the compiler.
457 inline const VectorType *getType() const {
458 return reinterpret_cast<const VectorType*>(Value::getType());
461 /// isNullValue - Return true if this is the value that would be returned by
462 /// getNullValue. This always returns false because zero vectors are always
463 /// created as ConstantAggregateZero objects.
464 virtual bool isNullValue() const { return false; }
466 /// This function will return true iff every element in this vector constant
467 /// is set to all ones.
468 /// @returns true iff this constant's emements are all set to all ones.
469 /// @brief Determine if the value is all ones.
470 bool isAllOnesValue() const;
472 /// getSplatValue - If this is a splat constant, meaning that all of the
473 /// elements have the same value, return that value. Otherwise return NULL.
474 Constant *getSplatValue();
476 virtual void destroyConstant();
477 virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
479 /// Methods for support type inquiry through isa, cast, and dyn_cast:
480 static inline bool classof(const ConstantVector *) { return true; }
481 static bool classof(const Value *V) {
482 return V->getValueID() == ConstantVectorVal;
487 struct OperandTraits<ConstantVector> : VariadicOperandTraits<> {
490 DEFINE_TRANSPARENT_CASTED_OPERAND_ACCESSORS(ConstantVector, Constant)
492 //===----------------------------------------------------------------------===//
493 /// ConstantPointerNull - a constant pointer value that points to null
495 class ConstantPointerNull : public Constant {
496 friend struct ConstantCreator<ConstantPointerNull, PointerType, char>;
497 void *operator new(size_t, unsigned); // DO NOT IMPLEMENT
498 ConstantPointerNull(const ConstantPointerNull &); // DO NOT IMPLEMENT
500 explicit ConstantPointerNull(const PointerType *T)
501 : Constant(reinterpret_cast<const Type*>(T),
502 Value::ConstantPointerNullVal, 0, 0) {}
505 // allocate space for exactly zero operands
506 void *operator new(size_t s) {
507 return User::operator new(s, 0);
510 /// get() - Static factory methods - Return objects of the specified value
511 static ConstantPointerNull *get(const PointerType *T);
513 /// isNullValue - Return true if this is the value that would be returned by
515 virtual bool isNullValue() const { return true; }
517 virtual void destroyConstant();
519 /// getType - Specialize the getType() method to always return an PointerType,
520 /// which reduces the amount of casting needed in parts of the compiler.
522 inline const PointerType *getType() const {
523 return reinterpret_cast<const PointerType*>(Value::getType());
526 /// Methods for support type inquiry through isa, cast, and dyn_cast:
527 static inline bool classof(const ConstantPointerNull *) { return true; }
528 static bool classof(const Value *V) {
529 return V->getValueID() == ConstantPointerNullVal;
534 /// ConstantExpr - a constant value that is initialized with an expression using
535 /// other constant values.
537 /// This class uses the standard Instruction opcodes to define the various
538 /// constant expressions. The Opcode field for the ConstantExpr class is
539 /// maintained in the Value::SubclassData field.
540 class ConstantExpr : public Constant {
541 friend struct ConstantCreator<ConstantExpr,Type,
542 std::pair<unsigned, std::vector<Constant*> > >;
543 friend struct ConvertConstantType<ConstantExpr, Type>;
546 ConstantExpr(const Type *ty, unsigned Opcode, Use *Ops, unsigned NumOps)
547 : Constant(ty, ConstantExprVal, Ops, NumOps) {
548 // Operation type (an Instruction opcode) is stored as the SubclassData.
549 SubclassData = Opcode;
552 // These private methods are used by the type resolution code to create
553 // ConstantExprs in intermediate forms.
554 static Constant *getTy(const Type *Ty, unsigned Opcode,
555 Constant *C1, Constant *C2);
556 static Constant *getCompareTy(unsigned short pred, Constant *C1,
558 static Constant *getSelectTy(const Type *Ty,
559 Constant *C1, Constant *C2, Constant *C3);
560 static Constant *getGetElementPtrTy(const Type *Ty, Constant *C,
561 Value* const *Idxs, unsigned NumIdxs);
562 static Constant *getExtractElementTy(const Type *Ty, Constant *Val,
564 static Constant *getInsertElementTy(const Type *Ty, Constant *Val,
565 Constant *Elt, Constant *Idx);
566 static Constant *getShuffleVectorTy(const Type *Ty, Constant *V1,
567 Constant *V2, Constant *Mask);
568 static Constant *getExtractValueTy(const Type *Ty, Constant *Agg,
569 const unsigned *Idxs, unsigned NumIdxs);
570 static Constant *getInsertValueTy(const Type *Ty, Constant *Agg,
572 const unsigned *Idxs, unsigned NumIdxs);
575 // Static methods to construct a ConstantExpr of different kinds. Note that
576 // these methods may return a object that is not an instance of the
577 // ConstantExpr class, because they will attempt to fold the constant
578 // expression into something simpler if possible.
580 /// Cast constant expr
582 static Constant *getTrunc (Constant *C, const Type *Ty);
583 static Constant *getSExt (Constant *C, const Type *Ty);
584 static Constant *getZExt (Constant *C, const Type *Ty);
585 static Constant *getFPTrunc (Constant *C, const Type *Ty);
586 static Constant *getFPExtend(Constant *C, const Type *Ty);
587 static Constant *getUIToFP (Constant *C, const Type *Ty);
588 static Constant *getSIToFP (Constant *C, const Type *Ty);
589 static Constant *getFPToUI (Constant *C, const Type *Ty);
590 static Constant *getFPToSI (Constant *C, const Type *Ty);
591 static Constant *getPtrToInt(Constant *C, const Type *Ty);
592 static Constant *getIntToPtr(Constant *C, const Type *Ty);
593 static Constant *getBitCast (Constant *C, const Type *Ty);
595 /// Transparently provide more efficient getOperand methods.
596 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
598 // @brief Convenience function for getting one of the casting operations
599 // using a CastOps opcode.
600 static Constant *getCast(
601 unsigned ops, ///< The opcode for the conversion
602 Constant *C, ///< The constant to be converted
603 const Type *Ty ///< The type to which the constant is converted
606 // @brief Create a ZExt or BitCast cast constant expression
607 static Constant *getZExtOrBitCast(
608 Constant *C, ///< The constant to zext or bitcast
609 const Type *Ty ///< The type to zext or bitcast C to
612 // @brief Create a SExt or BitCast cast constant expression
613 static Constant *getSExtOrBitCast(
614 Constant *C, ///< The constant to sext or bitcast
615 const Type *Ty ///< The type to sext or bitcast C to
618 // @brief Create a Trunc or BitCast cast constant expression
619 static Constant *getTruncOrBitCast(
620 Constant *C, ///< The constant to trunc or bitcast
621 const Type *Ty ///< The type to trunc or bitcast C to
624 /// @brief Create a BitCast or a PtrToInt cast constant expression
625 static Constant *getPointerCast(
626 Constant *C, ///< The pointer value to be casted (operand 0)
627 const Type *Ty ///< The type to which cast should be made
630 /// @brief Create a ZExt, Bitcast or Trunc for integer -> integer casts
631 static Constant *getIntegerCast(
632 Constant *C, ///< The integer constant to be casted
633 const Type *Ty, ///< The integer type to cast to
634 bool isSigned ///< Whether C should be treated as signed or not
637 /// @brief Create a FPExt, Bitcast or FPTrunc for fp -> fp casts
638 static Constant *getFPCast(
639 Constant *C, ///< The integer constant to be casted
640 const Type *Ty ///< The integer type to cast to
643 /// @brief Return true if this is a convert constant expression
646 /// @brief Return true if this is a compare constant expression
647 bool isCompare() const;
649 /// @brief Return true if this is an insertvalue or extractvalue expression,
650 /// and the getIndices() method may be used.
651 bool hasIndices() const;
653 /// Select constant expr
655 static Constant *getSelect(Constant *C, Constant *V1, Constant *V2) {
656 return getSelectTy(V1->getType(), C, V1, V2);
659 /// ConstantExpr::get - Return a binary or shift operator constant expression,
660 /// folding if possible.
662 static Constant *get(unsigned Opcode, Constant *C1, Constant *C2);
664 /// @brief Return an ICmp or FCmp comparison operator constant expression.
665 static Constant *getCompare(unsigned short pred, Constant *C1, Constant *C2);
667 /// ConstantExpr::get* - Return some common constants without having to
668 /// specify the full Instruction::OPCODE identifier.
670 static Constant *getICmp(unsigned short pred, Constant *LHS, Constant *RHS);
671 static Constant *getFCmp(unsigned short pred, Constant *LHS, Constant *RHS);
673 /// Getelementptr form. std::vector<Value*> is only accepted for convenience:
674 /// all elements must be Constant's.
676 static Constant *getGetElementPtr(Constant *C,
677 Constant* const *IdxList, unsigned NumIdx);
678 static Constant *getGetElementPtr(Constant *C,
679 Value* const *IdxList, unsigned NumIdx);
681 static Constant *getExtractElement(Constant *Vec, Constant *Idx);
682 static Constant *getInsertElement(Constant *Vec, Constant *Elt,Constant *Idx);
683 static Constant *getShuffleVector(Constant *V1, Constant *V2, Constant *Mask);
684 static Constant *getExtractValue(Constant *Agg,
685 const unsigned *IdxList, unsigned NumIdx);
686 static Constant *getInsertValue(Constant *Agg, Constant *Val,
687 const unsigned *IdxList, unsigned NumIdx);
689 /// isNullValue - Return true if this is the value that would be returned by
691 virtual bool isNullValue() const { return false; }
693 /// getOpcode - Return the opcode at the root of this constant expression
694 unsigned getOpcode() const { return SubclassData; }
696 /// getPredicate - Return the ICMP or FCMP predicate value. Assert if this is
697 /// not an ICMP or FCMP constant expression.
698 unsigned getPredicate() const;
700 /// getIndices - Assert that this is an insertvalue or exactvalue
701 /// expression and return the list of indices.
702 const SmallVector<unsigned, 4> &getIndices() const;
704 /// getOpcodeName - Return a string representation for an opcode.
705 const char *getOpcodeName() const;
707 /// getWithOperandReplaced - Return a constant expression identical to this
708 /// one, but with the specified operand set to the specified value.
709 Constant *getWithOperandReplaced(unsigned OpNo, Constant *Op) const;
711 /// getWithOperands - This returns the current constant expression with the
712 /// operands replaced with the specified values. The specified operands must
713 /// match count and type with the existing ones.
714 Constant *getWithOperands(const std::vector<Constant*> &Ops) const {
715 return getWithOperands(&Ops[0], (unsigned)Ops.size());
717 Constant *getWithOperands(Constant* const *Ops, unsigned NumOps) const;
719 virtual void destroyConstant();
720 virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);
722 /// Methods for support type inquiry through isa, cast, and dyn_cast:
723 static inline bool classof(const ConstantExpr *) { return true; }
724 static inline bool classof(const Value *V) {
725 return V->getValueID() == ConstantExprVal;
730 struct OperandTraits<ConstantExpr> : VariadicOperandTraits<1> {
733 DEFINE_TRANSPARENT_CASTED_OPERAND_ACCESSORS(ConstantExpr, Constant)
735 //===----------------------------------------------------------------------===//
736 /// UndefValue - 'undef' values are things that do not have specified contents.
737 /// These are used for a variety of purposes, including global variable
738 /// initializers and operands to instructions. 'undef' values can occur with
741 class UndefValue : public Constant {
742 friend struct ConstantCreator<UndefValue, Type, char>;
743 void *operator new(size_t, unsigned); // DO NOT IMPLEMENT
744 UndefValue(const UndefValue &); // DO NOT IMPLEMENT
746 explicit UndefValue(const Type *T) : Constant(T, UndefValueVal, 0, 0) {}
748 // allocate space for exactly zero operands
749 void *operator new(size_t s) {
750 return User::operator new(s, 0);
753 /// get() - Static factory methods - Return an 'undef' object of the specified
756 static UndefValue *get(const Type *T);
758 /// isNullValue - Return true if this is the value that would be returned by
760 virtual bool isNullValue() const { return false; }
762 virtual void destroyConstant();
764 /// Methods for support type inquiry through isa, cast, and dyn_cast:
765 static inline bool classof(const UndefValue *) { return true; }
766 static bool classof(const Value *V) {
767 return V->getValueID() == UndefValueVal;
770 } // End llvm namespace