1//===- llvm/DerivedTypes.h - Classes for handling data types ----*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 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... 13// 14// The implementations of these classes live in the Type.cpp file. 15// 16//===----------------------------------------------------------------------===// 17 18#ifndef LLVM_IR_DERIVEDTYPES_H 19#define LLVM_IR_DERIVEDTYPES_H 20 21#include "llvm/ADT/ArrayRef.h" 22#include "llvm/ADT/STLExtras.h" 23#include "llvm/ADT/StringRef.h" 24#include "llvm/IR/Type.h" 25#include "llvm/Support/Casting.h" 26#include "llvm/Support/Compiler.h" 27#include <cassert> 28#include <cstdint> 29 30namespace llvm { 31 32class Value; 33class APInt; 34class LLVMContext; 35 36/// Class to represent integer types. Note that this class is also used to 37/// represent the built-in integer types: Int1Ty, Int8Ty, Int16Ty, Int32Ty and 38/// Int64Ty. 39/// @brief Integer representation type 40class IntegerType : public Type { 41 friend class LLVMContextImpl; 42 43protected: 44 explicit IntegerType(LLVMContext &C, unsigned NumBits) : Type(C, IntegerTyID){ 45 setSubclassData(NumBits); 46 } 47 48public: 49 /// This enum is just used to hold constants we need for IntegerType. 50 enum { 51 MIN_INT_BITS = 1, ///< Minimum number of bits that can be specified 52 MAX_INT_BITS = (1<<24)-1 ///< Maximum number of bits that can be specified 53 ///< Note that bit width is stored in the Type classes SubclassData field 54 ///< which has 24 bits. This yields a maximum bit width of 16,777,215 55 ///< bits. 56 }; 57 58 /// This static method is the primary way of constructing an IntegerType. 59 /// If an IntegerType with the same NumBits value was previously instantiated, 60 /// that instance will be returned. Otherwise a new one will be created. Only 61 /// one instance with a given NumBits value is ever created. 62 /// @brief Get or create an IntegerType instance. 63 static IntegerType *get(LLVMContext &C, unsigned NumBits); 64 65 /// @brief Get the number of bits in this IntegerType 66 unsigned getBitWidth() const { return getSubclassData(); } 67 68 /// Return a bitmask with ones set for all of the bits that can be set by an 69 /// unsigned version of this type. This is 0xFF for i8, 0xFFFF for i16, etc. 70 uint64_t getBitMask() const { 71 return ~uint64_t(0UL) >> (64-getBitWidth()); 72 } 73 74 /// Return a uint64_t with just the most significant bit set (the sign bit, if 75 /// the value is treated as a signed number). 76 uint64_t getSignBit() const { 77 return 1ULL << (getBitWidth()-1); 78 } 79 80 /// For example, this is 0xFF for an 8 bit integer, 0xFFFF for i16, etc. 81 /// @returns a bit mask with ones set for all the bits of this type. 82 /// @brief Get a bit mask for this type. 83 APInt getMask() const; 84 85 /// This method determines if the width of this IntegerType is a power-of-2 86 /// in terms of 8 bit bytes. 87 /// @returns true if this is a power-of-2 byte width. 88 /// @brief Is this a power-of-2 byte-width IntegerType ? 89 bool isPowerOf2ByteWidth() const; 90 91 /// Methods for support type inquiry through isa, cast, and dyn_cast. 92 static bool classof(const Type *T) { 93 return T->getTypeID() == IntegerTyID; 94 } 95}; 96 97unsigned Type::getIntegerBitWidth() const { 98 return cast<IntegerType>(this)->getBitWidth(); 99} 100 101/// Class to represent function types 102/// 103class FunctionType : public Type { 104 FunctionType(Type *Result, ArrayRef<Type*> Params, bool IsVarArgs); 105 106public: 107 FunctionType(const FunctionType &) = delete; 108 FunctionType &operator=(const FunctionType &) = delete; 109 110 /// This static method is the primary way of constructing a FunctionType. 111 static FunctionType *get(Type *Result, 112 ArrayRef<Type*> Params, bool isVarArg); 113 114 /// Create a FunctionType taking no parameters. 115 static FunctionType *get(Type *Result, bool isVarArg); 116 117 /// Return true if the specified type is valid as a return type. 118 static bool isValidReturnType(Type *RetTy); 119 120 /// Return true if the specified type is valid as an argument type. 121 static bool isValidArgumentType(Type *ArgTy); 122 123 bool isVarArg() const { return getSubclassData()!=0; } 124 Type *getReturnType() const { return ContainedTys[0]; } 125 126 using param_iterator = Type::subtype_iterator; 127 128 param_iterator param_begin() const { return ContainedTys + 1; } 129 param_iterator param_end() const { return &ContainedTys[NumContainedTys]; } 130 ArrayRef<Type *> params() const { 131 return makeArrayRef(param_begin(), param_end()); 132 } 133 134 /// Parameter type accessors. 135 Type *getParamType(unsigned i) const { return ContainedTys[i+1]; } 136 137 /// Return the number of fixed parameters this function type requires. 138 /// This does not consider varargs. 139 unsigned getNumParams() const { return NumContainedTys - 1; } 140 141 /// Methods for support type inquiry through isa, cast, and dyn_cast. 142 static bool classof(const Type *T) { 143 return T->getTypeID() == FunctionTyID; 144 } 145}; 146static_assert(alignof(FunctionType) >= alignof(Type *), 147 "Alignment sufficient for objects appended to FunctionType"); 148 149bool Type::isFunctionVarArg() const { 150 return cast<FunctionType>(this)->isVarArg(); 151} 152 153Type *Type::getFunctionParamType(unsigned i) const { 154 return cast<FunctionType>(this)->getParamType(i); 155} 156 157unsigned Type::getFunctionNumParams() const { 158 return cast<FunctionType>(this)->getNumParams(); 159} 160 161/// Common super class of ArrayType, StructType and VectorType. 162class CompositeType : public Type { 163protected: 164 explicit CompositeType(LLVMContext &C, TypeID tid) : Type(C, tid) {} 165 166public: 167 /// Given an index value into the type, return the type of the element. 168 Type *getTypeAtIndex(const Value *V) const; 169 Type *getTypeAtIndex(unsigned Idx) const; 170 bool indexValid(const Value *V) const; 171 bool indexValid(unsigned Idx) const; 172 173 /// Methods for support type inquiry through isa, cast, and dyn_cast. 174 static bool classof(const Type *T) { 175 return T->getTypeID() == ArrayTyID || 176 T->getTypeID() == StructTyID || 177 T->getTypeID() == VectorTyID; 178 } 179}; 180 181/// Class to represent struct types. There are two different kinds of struct 182/// types: Literal structs and Identified structs. 183/// 184/// Literal struct types (e.g. { i32, i32 }) are uniqued structurally, and must 185/// always have a body when created. You can get one of these by using one of 186/// the StructType::get() forms. 187/// 188/// Identified structs (e.g. %foo or %42) may optionally have a name and are not 189/// uniqued. The names for identified structs are managed at the LLVMContext 190/// level, so there can only be a single identified struct with a given name in 191/// a particular LLVMContext. Identified structs may also optionally be opaque 192/// (have no body specified). You get one of these by using one of the 193/// StructType::create() forms. 194/// 195/// Independent of what kind of struct you have, the body of a struct type are 196/// laid out in memory consequtively with the elements directly one after the 197/// other (if the struct is packed) or (if not packed) with padding between the 198/// elements as defined by DataLayout (which is required to match what the code 199/// generator for a target expects). 200/// 201class StructType : public CompositeType { 202 StructType(LLVMContext &C) : CompositeType(C, StructTyID) {} 203 204 enum { 205 /// This is the contents of the SubClassData field. 206 SCDB_HasBody = 1, 207 SCDB_Packed = 2, 208 SCDB_IsLiteral = 4, 209 SCDB_IsSized = 8 210 }; 211 212 /// For a named struct that actually has a name, this is a pointer to the 213 /// symbol table entry (maintained by LLVMContext) for the struct. 214 /// This is null if the type is an literal struct or if it is a identified 215 /// type that has an empty name. 216 void *SymbolTableEntry = nullptr; 217 218public: 219 StructType(const StructType &) = delete; 220 StructType &operator=(const StructType &) = delete; 221 222 /// This creates an identified struct. 223 static StructType *create(LLVMContext &Context, StringRef Name); 224 static StructType *create(LLVMContext &Context); 225 226 static StructType *create(ArrayRef<Type *> Elements, StringRef Name, 227 bool isPacked = false); 228 static StructType *create(ArrayRef<Type *> Elements); 229 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements, 230 StringRef Name, bool isPacked = false); 231 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements); 232 template <class... Tys> 233 static typename std::enable_if<are_base_of<Type, Tys...>::value, 234 StructType *>::type 235 create(StringRef Name, Type *elt1, Tys *... elts) { 236 assert(elt1 && "Cannot create a struct type with no elements with this"); 237 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...}); 238 return create(StructFields, Name); 239 } 240 241 /// This static method is the primary way to create a literal StructType. 242 static StructType *get(LLVMContext &Context, ArrayRef<Type*> Elements, 243 bool isPacked = false); 244 245 /// Create an empty structure type. 246 static StructType *get(LLVMContext &Context, bool isPacked = false); 247 248 /// This static method is a convenience method for creating structure types by 249 /// specifying the elements as arguments. Note that this method always returns 250 /// a non-packed struct, and requires at least one element type. 251 template <class... Tys> 252 static typename std::enable_if<are_base_of<Type, Tys...>::value, 253 StructType *>::type 254 get(Type *elt1, Tys *... elts) { 255 assert(elt1 && "Cannot create a struct type with no elements with this"); 256 LLVMContext &Ctx = elt1->getContext(); 257 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...}); 258 return llvm::StructType::get(Ctx, StructFields); 259 } 260 261 bool isPacked() const { return (getSubclassData() & SCDB_Packed) != 0; } 262 263 /// Return true if this type is uniqued by structural equivalence, false if it 264 /// is a struct definition. 265 bool isLiteral() const { return (getSubclassData() & SCDB_IsLiteral) != 0; } 266 267 /// Return true if this is a type with an identity that has no body specified 268 /// yet. These prints as 'opaque' in .ll files. 269 bool isOpaque() const { return (getSubclassData() & SCDB_HasBody) == 0; } 270 271 /// isSized - Return true if this is a sized type. 272 bool isSized(SmallPtrSetImpl<Type *> *Visited = nullptr) const; 273 274 /// Return true if this is a named struct that has a non-empty name. 275 bool hasName() const { return SymbolTableEntry != nullptr; } 276 277 /// Return the name for this struct type if it has an identity. 278 /// This may return an empty string for an unnamed struct type. Do not call 279 /// this on an literal type. 280 StringRef getName() const; 281 282 /// Change the name of this type to the specified name, or to a name with a 283 /// suffix if there is a collision. Do not call this on an literal type. 284 void setName(StringRef Name); 285 286 /// Specify a body for an opaque identified type. 287 void setBody(ArrayRef<Type*> Elements, bool isPacked = false); 288 289 template <typename... Tys> 290 typename std::enable_if<are_base_of<Type, Tys...>::value, void>::type 291 setBody(Type *elt1, Tys *... elts) { 292 assert(elt1 && "Cannot create a struct type with no elements with this"); 293 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...}); 294 setBody(StructFields); 295 } 296 297 /// Return true if the specified type is valid as a element type. 298 static bool isValidElementType(Type *ElemTy); 299 300 // Iterator access to the elements. 301 using element_iterator = Type::subtype_iterator; 302 303 element_iterator element_begin() const { return ContainedTys; } 304 element_iterator element_end() const { return &ContainedTys[NumContainedTys];} 305 ArrayRef<Type *> const elements() const { 306 return makeArrayRef(element_begin(), element_end()); 307 } 308 309 /// Return true if this is layout identical to the specified struct. 310 bool isLayoutIdentical(StructType *Other) const; 311 312 /// Random access to the elements 313 unsigned getNumElements() const { return NumContainedTys; } 314 Type *getElementType(unsigned N) const { 315 assert(N < NumContainedTys && "Element number out of range!"); 316 return ContainedTys[N]; 317 } 318 319 /// Methods for support type inquiry through isa, cast, and dyn_cast. 320 static bool classof(const Type *T) { 321 return T->getTypeID() == StructTyID; 322 } 323}; 324 325StringRef Type::getStructName() const { 326 return cast<StructType>(this)->getName(); 327} 328 329unsigned Type::getStructNumElements() const { 330 return cast<StructType>(this)->getNumElements(); 331} 332 333Type *Type::getStructElementType(unsigned N) const { 334 return cast<StructType>(this)->getElementType(N); 335} 336 337/// This is the superclass of the array and vector type classes. Both of these 338/// represent "arrays" in memory. The array type represents a specifically sized 339/// array, and the vector type represents a specifically sized array that allows 340/// for use of SIMD instructions. SequentialType holds the common features of 341/// both, which stem from the fact that both lay their components out in memory 342/// identically. 343class SequentialType : public CompositeType { 344 Type *ContainedType; ///< Storage for the single contained type. 345 uint64_t NumElements; 346 347protected: 348 SequentialType(TypeID TID, Type *ElType, uint64_t NumElements) 349 : CompositeType(ElType->getContext(), TID), ContainedType(ElType), 350 NumElements(NumElements) { 351 ContainedTys = &ContainedType; 352 NumContainedTys = 1; 353 } 354 355public: 356 SequentialType(const SequentialType &) = delete; 357 SequentialType &operator=(const SequentialType &) = delete; 358 359 uint64_t getNumElements() const { return NumElements; } 360 Type *getElementType() const { return ContainedType; } 361 362 /// Methods for support type inquiry through isa, cast, and dyn_cast. 363 static bool classof(const Type *T) { 364 return T->getTypeID() == ArrayTyID || T->getTypeID() == VectorTyID; 365 } 366}; 367 368/// Class to represent array types. 369class ArrayType : public SequentialType { 370 ArrayType(Type *ElType, uint64_t NumEl); 371 372public: 373 ArrayType(const ArrayType &) = delete; 374 ArrayType &operator=(const ArrayType &) = delete; 375 376 /// This static method is the primary way to construct an ArrayType 377 static ArrayType *get(Type *ElementType, uint64_t NumElements); 378 379 /// Return true if the specified type is valid as a element type. 380 static bool isValidElementType(Type *ElemTy); 381 382 /// Methods for support type inquiry through isa, cast, and dyn_cast. 383 static bool classof(const Type *T) { 384 return T->getTypeID() == ArrayTyID; 385 } 386}; 387 388uint64_t Type::getArrayNumElements() const { 389 return cast<ArrayType>(this)->getNumElements(); 390} 391 392/// Class to represent vector types. 393class VectorType : public SequentialType { 394 VectorType(Type *ElType, unsigned NumEl); 395 396public: 397 VectorType(const VectorType &) = delete; 398 VectorType &operator=(const VectorType &) = delete; 399 400 /// This static method is the primary way to construct an VectorType. 401 static VectorType *get(Type *ElementType, unsigned NumElements); 402 403 /// This static method gets a VectorType with the same number of elements as 404 /// the input type, and the element type is an integer type of the same width 405 /// as the input element type. 406 static VectorType *getInteger(VectorType *VTy) { 407 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits(); 408 assert(EltBits && "Element size must be of a non-zero size"); 409 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits); 410 return VectorType::get(EltTy, VTy->getNumElements()); 411 } 412 413 /// This static method is like getInteger except that the element types are 414 /// twice as wide as the elements in the input type. 415 static VectorType *getExtendedElementVectorType(VectorType *VTy) { 416 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits(); 417 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits * 2); 418 return VectorType::get(EltTy, VTy->getNumElements()); 419 } 420 421 /// This static method is like getInteger except that the element types are 422 /// half as wide as the elements in the input type. 423 static VectorType *getTruncatedElementVectorType(VectorType *VTy) { 424 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits(); 425 assert((EltBits & 1) == 0 && 426 "Cannot truncate vector element with odd bit-width"); 427 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits / 2); 428 return VectorType::get(EltTy, VTy->getNumElements()); 429 } 430 431 /// This static method returns a VectorType with half as many elements as the 432 /// input type and the same element type. 433 static VectorType *getHalfElementsVectorType(VectorType *VTy) { 434 unsigned NumElts = VTy->getNumElements(); 435 assert ((NumElts & 1) == 0 && 436 "Cannot halve vector with odd number of elements."); 437 return VectorType::get(VTy->getElementType(), NumElts/2); 438 } 439 440 /// This static method returns a VectorType with twice as many elements as the 441 /// input type and the same element type. 442 static VectorType *getDoubleElementsVectorType(VectorType *VTy) { 443 unsigned NumElts = VTy->getNumElements(); 444 return VectorType::get(VTy->getElementType(), NumElts*2); 445 } 446 447 /// Return true if the specified type is valid as a element type. 448 static bool isValidElementType(Type *ElemTy); 449 450 /// Return the number of bits in the Vector type. 451 /// Returns zero when the vector is a vector of pointers. 452 unsigned getBitWidth() const { 453 return getNumElements() * getElementType()->getPrimitiveSizeInBits(); 454 } 455 456 /// Methods for support type inquiry through isa, cast, and dyn_cast. 457 static bool classof(const Type *T) { 458 return T->getTypeID() == VectorTyID; 459 } 460}; 461 462unsigned Type::getVectorNumElements() const { 463 return cast<VectorType>(this)->getNumElements(); 464} 465 466/// Class to represent pointers. 467class PointerType : public Type { 468 explicit PointerType(Type *ElType, unsigned AddrSpace); 469 470 Type *PointeeTy; 471 472public: 473 PointerType(const PointerType &) = delete; 474 PointerType &operator=(const PointerType &) = delete; 475 476 /// This constructs a pointer to an object of the specified type in a numbered 477 /// address space. 478 static PointerType *get(Type *ElementType, unsigned AddressSpace); 479 480 /// This constructs a pointer to an object of the specified type in the 481 /// generic address space (address space zero). 482 static PointerType *getUnqual(Type *ElementType) { 483 return PointerType::get(ElementType, 0); 484 } 485 486 Type *getElementType() const { return PointeeTy; } 487 488 /// Return true if the specified type is valid as a element type. 489 static bool isValidElementType(Type *ElemTy); 490 491 /// Return true if we can load or store from a pointer to this type. 492 static bool isLoadableOrStorableType(Type *ElemTy); 493 494 /// Return the address space of the Pointer type. 495 inline unsigned getAddressSpace() const { return getSubclassData(); } 496 497 /// Implement support type inquiry through isa, cast, and dyn_cast. 498 static bool classof(const Type *T) { 499 return T->getTypeID() == PointerTyID; 500 } 501}; 502 503unsigned Type::getPointerAddressSpace() const { 504 return cast<PointerType>(getScalarType())->getAddressSpace(); 505} 506 507} // end namespace llvm 508 509#endif // LLVM_IR_DERIVEDTYPES_H 510