1 //===-- llvm/DerivedTypes.h - Classes for handling data types ---*- 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 //===----------------------------------------------------------------------===//
10 // This file contains the declarations of classes that represent "derived
11 // types". These are things like "arrays of x" or "structure of x, y, z" or
12 // "function returning x taking (y,z) as parameters", etc...
14 // The implementations of these classes live in the Type.cpp file.
16 //===----------------------------------------------------------------------===//
18 #ifndef LLVM_IR_DERIVEDTYPES_H
19 #define LLVM_IR_DERIVEDTYPES_H
21 #include "llvm/IR/Type.h"
22 #include "llvm/Support/Compiler.h"
23 #include "llvm/Support/DataTypes.h"
30 template<typename T> class ArrayRef;
33 /// Class to represent integer types. Note that this class is also used to
34 /// represent the built-in integer types: Int1Ty, Int8Ty, Int16Ty, Int32Ty and
36 /// @brief Integer representation type
37 class IntegerType : public Type {
38 friend class LLVMContextImpl;
41 explicit IntegerType(LLVMContext &C, unsigned NumBits) : Type(C, IntegerTyID){
42 setSubclassData(NumBits);
46 /// This enum is just used to hold constants we need for IntegerType.
48 MIN_INT_BITS = 1, ///< Minimum number of bits that can be specified
49 MAX_INT_BITS = (1<<23)-1 ///< Maximum number of bits that can be specified
50 ///< Note that bit width is stored in the Type classes SubclassData field
51 ///< which has 23 bits. This yields a maximum bit width of 8,388,607 bits.
54 /// This static method is the primary way of constructing an IntegerType.
55 /// If an IntegerType with the same NumBits value was previously instantiated,
56 /// that instance will be returned. Otherwise a new one will be created. Only
57 /// one instance with a given NumBits value is ever created.
58 /// @brief Get or create an IntegerType instance.
59 static IntegerType *get(LLVMContext &C, unsigned NumBits);
61 /// @brief Get the number of bits in this IntegerType
62 unsigned getBitWidth() const { return getSubclassData(); }
64 /// getBitMask - Return a bitmask with ones set for all of the bits
65 /// that can be set by an unsigned version of this type. This is 0xFF for
66 /// i8, 0xFFFF for i16, etc.
67 uint64_t getBitMask() const {
68 return ~uint64_t(0UL) >> (64-getBitWidth());
71 /// getSignBit - Return a uint64_t with just the most significant bit set (the
72 /// sign bit, if the value is treated as a signed number).
73 uint64_t getSignBit() const {
74 return 1ULL << (getBitWidth()-1);
77 /// For example, this is 0xFF for an 8 bit integer, 0xFFFF for i16, etc.
78 /// @returns a bit mask with ones set for all the bits of this type.
79 /// @brief Get a bit mask for this type.
80 APInt getMask() const;
82 /// This method determines if the width of this IntegerType is a power-of-2
83 /// in terms of 8 bit bytes.
84 /// @returns true if this is a power-of-2 byte width.
85 /// @brief Is this a power-of-2 byte-width IntegerType ?
86 bool isPowerOf2ByteWidth() const;
88 /// Methods for support type inquiry through isa, cast, and dyn_cast.
89 static inline bool classof(const Type *T) {
90 return T->getTypeID() == IntegerTyID;
94 /// FunctionType - Class to represent function types
96 class FunctionType : public Type {
97 FunctionType(const FunctionType &) = delete;
98 const FunctionType &operator=(const FunctionType &) = delete;
99 FunctionType(Type *Result, ArrayRef<Type*> Params, bool IsVarArgs);
102 /// FunctionType::get - This static method is the primary way of constructing
105 static FunctionType *get(Type *Result,
106 ArrayRef<Type*> Params, bool isVarArg);
108 /// FunctionType::get - Create a FunctionType taking no parameters.
110 static FunctionType *get(Type *Result, bool isVarArg);
112 /// isValidReturnType - Return true if the specified type is valid as a return
114 static bool isValidReturnType(Type *RetTy);
116 /// isValidArgumentType - Return true if the specified type is valid as an
118 static bool isValidArgumentType(Type *ArgTy);
120 bool isVarArg() const { return getSubclassData()!=0; }
121 Type *getReturnType() const { return ContainedTys[0]; }
123 typedef Type::subtype_iterator param_iterator;
124 param_iterator param_begin() const { return ContainedTys + 1; }
125 param_iterator param_end() const { return &ContainedTys[NumContainedTys]; }
126 ArrayRef<Type *> params() const {
127 return makeArrayRef(param_begin(), param_end());
130 /// Parameter type accessors.
131 Type *getParamType(unsigned i) const { return ContainedTys[i+1]; }
133 /// getNumParams - Return the number of fixed parameters this function type
134 /// requires. This does not consider varargs.
136 unsigned getNumParams() const { return NumContainedTys - 1; }
138 /// Methods for support type inquiry through isa, cast, and dyn_cast.
139 static inline bool classof(const Type *T) {
140 return T->getTypeID() == FunctionTyID;
143 static_assert(AlignOf<FunctionType>::Alignment >= AlignOf<Type *>::Alignment,
144 "Alignment sufficient for objects appended to FunctionType");
146 /// CompositeType - Common super class of ArrayType, StructType, PointerType
148 class CompositeType : public Type {
150 explicit CompositeType(LLVMContext &C, TypeID tid) : Type(C, tid) {}
153 /// getTypeAtIndex - Given an index value into the type, return the type of
156 Type *getTypeAtIndex(const Value *V) const;
157 Type *getTypeAtIndex(unsigned Idx) const;
158 bool indexValid(const Value *V) const;
159 bool indexValid(unsigned Idx) const;
161 /// Methods for support type inquiry through isa, cast, and dyn_cast.
162 static inline bool classof(const Type *T) {
163 return T->getTypeID() == ArrayTyID ||
164 T->getTypeID() == StructTyID ||
165 T->getTypeID() == PointerTyID ||
166 T->getTypeID() == VectorTyID;
170 /// StructType - Class to represent struct types. There are two different kinds
171 /// of struct types: Literal structs and Identified structs.
173 /// Literal struct types (e.g. { i32, i32 }) are uniqued structurally, and must
174 /// always have a body when created. You can get one of these by using one of
175 /// the StructType::get() forms.
177 /// Identified structs (e.g. %foo or %42) may optionally have a name and are not
178 /// uniqued. The names for identified structs are managed at the LLVMContext
179 /// level, so there can only be a single identified struct with a given name in
180 /// a particular LLVMContext. Identified structs may also optionally be opaque
181 /// (have no body specified). You get one of these by using one of the
182 /// StructType::create() forms.
184 /// Independent of what kind of struct you have, the body of a struct type are
185 /// laid out in memory consequtively with the elements directly one after the
186 /// other (if the struct is packed) or (if not packed) with padding between the
187 /// elements as defined by DataLayout (which is required to match what the code
188 /// generator for a target expects).
190 class StructType : public CompositeType {
191 StructType(const StructType &) = delete;
192 const StructType &operator=(const StructType &) = delete;
193 StructType(LLVMContext &C)
194 : CompositeType(C, StructTyID), SymbolTableEntry(nullptr) {}
196 /// This is the contents of the SubClassData field.
203 /// SymbolTableEntry - For a named struct that actually has a name, this is a
204 /// pointer to the symbol table entry (maintained by LLVMContext) for the
205 /// struct. This is null if the type is an literal struct or if it is
206 /// a identified type that has an empty name.
208 void *SymbolTableEntry;
211 /// StructType::create - This creates an identified struct.
212 static StructType *create(LLVMContext &Context, StringRef Name);
213 static StructType *create(LLVMContext &Context);
215 static StructType *create(ArrayRef<Type *> Elements, StringRef Name,
216 bool isPacked = false);
217 static StructType *create(ArrayRef<Type *> Elements);
218 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements,
219 StringRef Name, bool isPacked = false);
220 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements);
221 static StructType *create(StringRef Name, Type *elt1, ...) LLVM_END_WITH_NULL;
223 /// StructType::get - This static method is the primary way to create a
224 /// literal StructType.
225 static StructType *get(LLVMContext &Context, ArrayRef<Type*> Elements,
226 bool isPacked = false);
228 /// StructType::get - Create an empty structure type.
230 static StructType *get(LLVMContext &Context, bool isPacked = false);
232 /// StructType::get - This static method is a convenience method for creating
233 /// structure types by specifying the elements as arguments. Note that this
234 /// method always returns a non-packed struct, and requires at least one
236 static StructType *get(Type *elt1, ...) LLVM_END_WITH_NULL;
238 bool isPacked() const { return (getSubclassData() & SCDB_Packed) != 0; }
240 /// isLiteral - Return true if this type is uniqued by structural
241 /// equivalence, false if it is a struct definition.
242 bool isLiteral() const { return (getSubclassData() & SCDB_IsLiteral) != 0; }
244 /// isOpaque - Return true if this is a type with an identity that has no body
245 /// specified yet. These prints as 'opaque' in .ll files.
246 bool isOpaque() const { return (getSubclassData() & SCDB_HasBody) == 0; }
248 /// isSized - Return true if this is a sized type.
249 bool isSized(SmallPtrSetImpl<Type *> *Visited = nullptr) const;
251 /// hasName - Return true if this is a named struct that has a non-empty name.
252 bool hasName() const { return SymbolTableEntry != nullptr; }
254 /// getName - Return the name for this struct type if it has an identity.
255 /// This may return an empty string for an unnamed struct type. Do not call
256 /// this on an literal type.
257 StringRef getName() const;
259 /// setName - Change the name of this type to the specified name, or to a name
260 /// with a suffix if there is a collision. Do not call this on an literal
262 void setName(StringRef Name);
264 /// setBody - Specify a body for an opaque identified type.
265 void setBody(ArrayRef<Type*> Elements, bool isPacked = false);
266 void setBody(Type *elt1, ...) LLVM_END_WITH_NULL;
268 /// isValidElementType - Return true if the specified type is valid as a
270 static bool isValidElementType(Type *ElemTy);
272 // Iterator access to the elements.
273 typedef Type::subtype_iterator element_iterator;
274 element_iterator element_begin() const { return ContainedTys; }
275 element_iterator element_end() const { return &ContainedTys[NumContainedTys];}
276 ArrayRef<Type *> const elements() const {
277 return makeArrayRef(element_begin(), element_end());
280 /// isLayoutIdentical - Return true if this is layout identical to the
281 /// specified struct.
282 bool isLayoutIdentical(StructType *Other) const;
284 /// Random access to the elements
285 unsigned getNumElements() const { return NumContainedTys; }
286 Type *getElementType(unsigned N) const {
287 assert(N < NumContainedTys && "Element number out of range!");
288 return ContainedTys[N];
291 /// Methods for support type inquiry through isa, cast, and dyn_cast.
292 static inline bool classof(const Type *T) {
293 return T->getTypeID() == StructTyID;
297 /// SequentialType - This is the superclass of the array, pointer and vector
298 /// type classes. All of these represent "arrays" in memory. The array type
299 /// represents a specifically sized array, pointer types are unsized/unknown
300 /// size arrays, vector types represent specifically sized arrays that
301 /// allow for use of SIMD instructions. SequentialType holds the common
302 /// features of all, which stem from the fact that all three lay their
303 /// components out in memory identically.
305 class SequentialType : public CompositeType {
306 Type *ContainedType; ///< Storage for the single contained type.
307 SequentialType(const SequentialType &) = delete;
308 const SequentialType &operator=(const SequentialType &) = delete;
311 SequentialType(TypeID TID, Type *ElType)
312 : CompositeType(ElType->getContext(), TID), ContainedType(ElType) {
313 ContainedTys = &ContainedType;
318 Type *getElementType() const { return ContainedTys[0]; }
320 /// Methods for support type inquiry through isa, cast, and dyn_cast.
321 static inline bool classof(const Type *T) {
322 return T->getTypeID() == ArrayTyID ||
323 T->getTypeID() == PointerTyID ||
324 T->getTypeID() == VectorTyID;
328 /// ArrayType - Class to represent array types.
330 class ArrayType : public SequentialType {
331 uint64_t NumElements;
333 ArrayType(const ArrayType &) = delete;
334 const ArrayType &operator=(const ArrayType &) = delete;
335 ArrayType(Type *ElType, uint64_t NumEl);
338 /// ArrayType::get - This static method is the primary way to construct an
341 static ArrayType *get(Type *ElementType, uint64_t NumElements);
343 /// isValidElementType - Return true if the specified type is valid as a
345 static bool isValidElementType(Type *ElemTy);
347 uint64_t getNumElements() const { return NumElements; }
349 /// Methods for support type inquiry through isa, cast, and dyn_cast.
350 static inline bool classof(const Type *T) {
351 return T->getTypeID() == ArrayTyID;
355 /// VectorType - Class to represent vector types.
357 class VectorType : public SequentialType {
358 unsigned NumElements;
360 VectorType(const VectorType &) = delete;
361 const VectorType &operator=(const VectorType &) = delete;
362 VectorType(Type *ElType, unsigned NumEl);
365 /// VectorType::get - This static method is the primary way to construct an
368 static VectorType *get(Type *ElementType, unsigned NumElements);
370 /// VectorType::getInteger - This static method gets a VectorType with the
371 /// same number of elements as the input type, and the element type is an
372 /// integer type of the same width as the input element type.
374 static VectorType *getInteger(VectorType *VTy) {
375 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
376 assert(EltBits && "Element size must be of a non-zero size");
377 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits);
378 return VectorType::get(EltTy, VTy->getNumElements());
381 /// VectorType::getExtendedElementVectorType - This static method is like
382 /// getInteger except that the element types are twice as wide as the
383 /// elements in the input type.
385 static VectorType *getExtendedElementVectorType(VectorType *VTy) {
386 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
387 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits * 2);
388 return VectorType::get(EltTy, VTy->getNumElements());
391 /// VectorType::getTruncatedElementVectorType - This static method is like
392 /// getInteger except that the element types are half as wide as the
393 /// elements in the input type.
395 static VectorType *getTruncatedElementVectorType(VectorType *VTy) {
396 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
397 assert((EltBits & 1) == 0 &&
398 "Cannot truncate vector element with odd bit-width");
399 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits / 2);
400 return VectorType::get(EltTy, VTy->getNumElements());
403 /// VectorType::getHalfElementsVectorType - This static method returns
404 /// a VectorType with half as many elements as the input type and the
405 /// same element type.
407 static VectorType *getHalfElementsVectorType(VectorType *VTy) {
408 unsigned NumElts = VTy->getNumElements();
409 assert ((NumElts & 1) == 0 &&
410 "Cannot halve vector with odd number of elements.");
411 return VectorType::get(VTy->getElementType(), NumElts/2);
414 /// VectorType::getDoubleElementsVectorType - This static method returns
415 /// a VectorType with twice as many elements as the input type and the
416 /// same element type.
418 static VectorType *getDoubleElementsVectorType(VectorType *VTy) {
419 unsigned NumElts = VTy->getNumElements();
420 return VectorType::get(VTy->getElementType(), NumElts*2);
423 /// isValidElementType - Return true if the specified type is valid as a
425 static bool isValidElementType(Type *ElemTy);
427 /// @brief Return the number of elements in the Vector type.
428 unsigned getNumElements() const { return NumElements; }
430 /// @brief Return the number of bits in the Vector type.
431 /// Returns zero when the vector is a vector of pointers.
432 unsigned getBitWidth() const {
433 return NumElements * getElementType()->getPrimitiveSizeInBits();
436 /// Methods for support type inquiry through isa, cast, and dyn_cast.
437 static inline bool classof(const Type *T) {
438 return T->getTypeID() == VectorTyID;
442 /// PointerType - Class to represent pointers.
444 class PointerType : public SequentialType {
445 PointerType(const PointerType &) = delete;
446 const PointerType &operator=(const PointerType &) = delete;
447 explicit PointerType(Type *ElType, unsigned AddrSpace);
450 /// PointerType::get - This constructs a pointer to an object of the specified
451 /// type in a numbered address space.
452 static PointerType *get(Type *ElementType, unsigned AddressSpace);
454 /// PointerType::getUnqual - This constructs a pointer to an object of the
455 /// specified type in the generic address space (address space zero).
456 static PointerType *getUnqual(Type *ElementType) {
457 return PointerType::get(ElementType, 0);
460 /// isValidElementType - Return true if the specified type is valid as a
462 static bool isValidElementType(Type *ElemTy);
464 /// Return true if we can load or store from a pointer to this type.
465 static bool isLoadableOrStorableType(Type *ElemTy);
467 /// @brief Return the address space of the Pointer type.
468 inline unsigned getAddressSpace() const { return getSubclassData(); }
470 /// Implement support type inquiry through isa, cast, and dyn_cast.
471 static inline bool classof(const Type *T) {
472 return T->getTypeID() == PointerTyID;
476 } // End llvm namespace