include/llvm/IR/Type.h

   1 //===- llvm/Type.h - Classes for handling data types ------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains the declaration of the Type class.  For more "Type"
  10 // stuff, look in DerivedTypes.h.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_IR_TYPE_H
  15 #define LLVM_IR_TYPE_H
  16
  17 #include "llvm/ADT/APFloat.h"
  18 #include "llvm/ADT/ArrayRef.h"
  19 #include "llvm/ADT/SmallPtrSet.h"
  20 #include "llvm/Support/CBindingWrapping.h"
  21 #include "llvm/Support/Casting.h"
  22 #include "llvm/Support/Compiler.h"
  23 #include "llvm/Support/ErrorHandling.h"
  24 #include "llvm/Support/TypeSize.h"
  25 #include <cassert>
  26 #include <cstdint>
  27 #include <iterator>
  28
  29 namespace llvm {
  30
  31 template<class GraphType> struct GraphTraits;
  32 class IntegerType;
  33 class LLVMContext;
  34 class PointerType;
  35 class raw_ostream;
  36 class StringRef;
  37
  38 /// The instances of the Type class are immutable: once they are created,
  39 /// they are never changed.  Also note that only one instance of a particular
  40 /// type is ever created.  Thus seeing if two types are equal is a matter of
  41 /// doing a trivial pointer comparison. To enforce that no two equal instances
  42 /// are created, Type instances can only be created via static factory methods
  43 /// in class Type and in derived classes.  Once allocated, Types are never
  44 /// free'd.
  45 ///
  46 class Type {
  47 public:
  48   //===--------------------------------------------------------------------===//
  49   /// Definitions of all of the base types for the Type system.  Based on this
  50   /// value, you can cast to a class defined in DerivedTypes.h.
  51   /// Note: If you add an element to this, you need to add an element to the
  52   /// Type::getPrimitiveType function, or else things will break!
  53   /// Also update LLVMTypeKind and LLVMGetTypeKind () in the C binding.
  54   ///
  55   enum TypeID {
  56     // PrimitiveTypes - make sure LastPrimitiveTyID stays up to date.
  57     VoidTyID = 0,    ///<  0: type with no size
  58     HalfTyID,        ///<  1: 16-bit floating point type
  59     FloatTyID,       ///<  2: 32-bit floating point type
  60     DoubleTyID,      ///<  3: 64-bit floating point type
  61     X86_FP80TyID,    ///<  4: 80-bit floating point type (X87)
  62     FP128TyID,       ///<  5: 128-bit floating point type (112-bit mantissa)
  63     PPC_FP128TyID,   ///<  6: 128-bit floating point type (two 64-bits, PowerPC)
  64     LabelTyID,       ///<  7: Labels
  65     MetadataTyID,    ///<  8: Metadata
  66     X86_MMXTyID,     ///<  9: MMX vectors (64 bits, X86 specific)
  67     TokenTyID,       ///< 10: Tokens
  68
  69     // Derived types... see DerivedTypes.h file.
  70     // Make sure FirstDerivedTyID stays up to date!
  71     IntegerTyID,     ///< 11: Arbitrary bit width integers
  72     FunctionTyID,    ///< 12: Functions
  73     StructTyID,      ///< 13: Structures
  74     ArrayTyID,       ///< 14: Arrays
  75     PointerTyID,     ///< 15: Pointers
  76     VectorTyID       ///< 16: SIMD 'packed' format, or other vector type
  77   };
  78
  79 private:
  80   /// This refers to the LLVMContext in which this type was uniqued.
  81   LLVMContext &Context;
  82
  83   TypeID   ID : 8;            // The current base type of this type.
  84   unsigned SubclassData : 24; // Space for subclasses to store data.
  85                               // Note that this should be synchronized with
  86                               // MAX_INT_BITS value in IntegerType class.
  87
  88 protected:
  89   friend class LLVMContextImpl;
  90
  91   explicit Type(LLVMContext &C, TypeID tid)
  92     : Context(C), ID(tid), SubclassData(0) {}
  93   ~Type() = default;
  94
  95   unsigned getSubclassData() const { return SubclassData; }
  96
  97   void setSubclassData(unsigned val) {
  98     SubclassData = val;
  99     // Ensure we don't have any accidental truncation.
 100     assert(getSubclassData() == val && "Subclass data too large for field");
 101   }
 102
 103   /// Keeps track of how many Type*'s there are in the ContainedTys list.
 104   unsigned NumContainedTys = 0;
 105
 106   /// A pointer to the array of Types contained by this Type. For example, this
 107   /// includes the arguments of a function type, the elements of a structure,
 108   /// the pointee of a pointer, the element type of an array, etc. This pointer
 109   /// may be 0 for types that don't contain other types (Integer, Double,
 110   /// Float).
 111   Type * const *ContainedTys = nullptr;
 112
 113   static bool isSequentialType(TypeID TyID) {
 114     return TyID == ArrayTyID || TyID == VectorTyID;
 115   }
 116
 117 public:
 118   /// Print the current type.
 119   /// Omit the type details if \p NoDetails == true.
 120   /// E.g., let %st = type { i32, i16 }
 121   /// When \p NoDetails is true, we only print %st.
 122   /// Put differently, \p NoDetails prints the type as if
 123   /// inlined with the operands when printing an instruction.
 124   void print(raw_ostream &O, bool IsForDebug = false,
 125              bool NoDetails = false) const;
 126
 127   void dump() const;
 128
 129   /// Return the LLVMContext in which this type was uniqued.
 130   LLVMContext &getContext() const { return Context; }
 131
 132   //===--------------------------------------------------------------------===//
 133   // Accessors for working with types.
 134   //
 135
 136   /// Return the type id for the type. This will return one of the TypeID enum
 137   /// elements defined above.
 138   TypeID getTypeID() const { return ID; }
 139
 140   /// Return true if this is 'void'.
 141   bool isVoidTy() const { return getTypeID() == VoidTyID; }
 142
 143   /// Return true if this is 'half', a 16-bit IEEE fp type.
 144   bool isHalfTy() const { return getTypeID() == HalfTyID; }
 145
 146   /// Return true if this is 'float', a 32-bit IEEE fp type.
 147   bool isFloatTy() const { return getTypeID() == FloatTyID; }
 148
 149   /// Return true if this is 'double', a 64-bit IEEE fp type.
 150   bool isDoubleTy() const { return getTypeID() == DoubleTyID; }
 151
 152   /// Return true if this is x86 long double.
 153   bool isX86_FP80Ty() const { return getTypeID() == X86_FP80TyID; }
 154
 155   /// Return true if this is 'fp128'.
 156   bool isFP128Ty() const { return getTypeID() == FP128TyID; }
 157
 158   /// Return true if this is powerpc long double.
 159   bool isPPC_FP128Ty() const { return getTypeID() == PPC_FP128TyID; }
 160
 161   /// Return true if this is one of the six floating-point types
 162   bool isFloatingPointTy() const {
 163     return getTypeID() == HalfTyID || getTypeID() == FloatTyID ||
 164            getTypeID() == DoubleTyID ||
 165            getTypeID() == X86_FP80TyID || getTypeID() == FP128TyID ||
 166            getTypeID() == PPC_FP128TyID;
 167   }
 168
 169   const fltSemantics &getFltSemantics() const {
 170     switch (getTypeID()) {
 171     case HalfTyID: return APFloat::IEEEhalf();
 172     case FloatTyID: return APFloat::IEEEsingle();
 173     case DoubleTyID: return APFloat::IEEEdouble();
 174     case X86_FP80TyID: return APFloat::x87DoubleExtended();
 175     case FP128TyID: return APFloat::IEEEquad();
 176     case PPC_FP128TyID: return APFloat::PPCDoubleDouble();
 177     default: llvm_unreachable("Invalid floating type");
 178     }
 179   }
 180
 181   /// Return true if this is X86 MMX.
 182   bool isX86_MMXTy() const { return getTypeID() == X86_MMXTyID; }
 183
 184   /// Return true if this is a FP type or a vector of FP.
 185   bool isFPOrFPVectorTy() const { return getScalarType()->isFloatingPointTy(); }
 186
 187   /// Return true if this is 'label'.
 188   bool isLabelTy() const { return getTypeID() == LabelTyID; }
 189
 190   /// Return true if this is 'metadata'.
 191   bool isMetadataTy() const { return getTypeID() == MetadataTyID; }
 192
 193   /// Return true if this is 'token'.
 194   bool isTokenTy() const { return getTypeID() == TokenTyID; }
 195
 196   /// True if this is an instance of IntegerType.
 197   bool isIntegerTy() const { return getTypeID() == IntegerTyID; }
 198
 199   /// Return true if this is an IntegerType of the given width.
 200   bool isIntegerTy(unsigned Bitwidth) const;
 201
 202   /// Return true if this is an integer type or a vector of integer types.
 203   bool isIntOrIntVectorTy() const { return getScalarType()->isIntegerTy(); }
 204
 205   /// Return true if this is an integer type or a vector of integer types of
 206   /// the given width.
 207   bool isIntOrIntVectorTy(unsigned BitWidth) const {
 208     return getScalarType()->isIntegerTy(BitWidth);
 209   }
 210
 211   /// Return true if this is an integer type or a pointer type.
 212   bool isIntOrPtrTy() const { return isIntegerTy() || isPointerTy(); }
 213
 214   /// True if this is an instance of FunctionType.
 215   bool isFunctionTy() const { return getTypeID() == FunctionTyID; }
 216
 217   /// True if this is an instance of StructType.
 218   bool isStructTy() const { return getTypeID() == StructTyID; }
 219
 220   /// True if this is an instance of ArrayType.
 221   bool isArrayTy() const { return getTypeID() == ArrayTyID; }
 222
 223   /// True if this is an instance of PointerType.
 224   bool isPointerTy() const { return getTypeID() == PointerTyID; }
 225
 226   /// Return true if this is a pointer type or a vector of pointer types.
 227   bool isPtrOrPtrVectorTy() const { return getScalarType()->isPointerTy(); }
 228
 229   /// True if this is an instance of VectorType.
 230   bool isVectorTy() const { return getTypeID() == VectorTyID; }
 231
 232   /// Return true if this type could be converted with a lossless BitCast to
 233   /// type 'Ty'. For example, i8* to i32*. BitCasts are valid for types of the
 234   /// same size only where no re-interpretation of the bits is done.
 235   /// Determine if this type could be losslessly bitcast to Ty
 236   bool canLosslesslyBitCastTo(Type *Ty) const;
 237
 238   /// Return true if this type is empty, that is, it has no elements or all of
 239   /// its elements are empty.
 240   bool isEmptyTy() const;
 241
 242   /// Return true if the type is "first class", meaning it is a valid type for a
 243   /// Value.
 244   bool isFirstClassType() const {
 245     return getTypeID() != FunctionTyID && getTypeID() != VoidTyID;
 246   }
 247
 248   /// Return true if the type is a valid type for a register in codegen. This
 249   /// includes all first-class types except struct and array types.
 250   bool isSingleValueType() const {
 251     return isFloatingPointTy() || isX86_MMXTy() || isIntegerTy() ||
 252            isPointerTy() || isVectorTy();
 253   }
 254
 255   /// Return true if the type is an aggregate type. This means it is valid as
 256   /// the first operand of an insertvalue or extractvalue instruction. This
 257   /// includes struct and array types, but does not include vector types.
 258   bool isAggregateType() const {
 259     return getTypeID() == StructTyID || getTypeID() == ArrayTyID;
 260   }
 261
 262   /// Return true if it makes sense to take the size of this type. To get the
 263   /// actual size for a particular target, it is reasonable to use the
 264   /// DataLayout subsystem to do this.
 265   bool isSized(SmallPtrSetImpl<Type*> *Visited = nullptr) const {
 266     // If it's a primitive, it is always sized.
 267     if (getTypeID() == IntegerTyID || isFloatingPointTy() ||
 268         getTypeID() == PointerTyID ||
 269         getTypeID() == X86_MMXTyID)
 270       return true;
 271     // If it is not something that can have a size (e.g. a function or label),
 272     // it doesn't have a size.
 273     if (getTypeID() != StructTyID && getTypeID() != ArrayTyID &&
 274         getTypeID() != VectorTyID)
 275       return false;
 276     // Otherwise we have to try harder to decide.
 277     return isSizedDerivedType(Visited);
 278   }
 279
 280   /// Return the basic size of this type if it is a primitive type. These are
 281   /// fixed by LLVM and are not target-dependent.
 282   /// This will return zero if the type does not have a size or is not a
 283   /// primitive type.
 284   ///
 285   /// If this is a scalable vector type, the scalable property will be set and
 286   /// the runtime size will be a positive integer multiple of the base size.
 287   ///
 288   /// Note that this may not reflect the size of memory allocated for an
 289   /// instance of the type or the number of bytes that are written when an
 290   /// instance of the type is stored to memory. The DataLayout class provides
 291   /// additional query functions to provide this information.
 292   ///
 293   TypeSize getPrimitiveSizeInBits() const LLVM_READONLY;
 294
 295   /// If this is a vector type, return the getPrimitiveSizeInBits value for the
 296   /// element type. Otherwise return the getPrimitiveSizeInBits value for this
 297   /// type.
 298   unsigned getScalarSizeInBits() const LLVM_READONLY;
 299
 300   /// Return the width of the mantissa of this type. This is only valid on
 301   /// floating-point types. If the FP type does not have a stable mantissa (e.g.
 302   /// ppc long double), this method returns -1.
 303   int getFPMantissaWidth() const;
 304
 305   /// If this is a vector type, return the element type, otherwise return
 306   /// 'this'.
 307   Type *getScalarType() const {
 308     if (isVectorTy())
 309       return getVectorElementType();
 310     return const_cast<Type*>(this);
 311   }
 312
 313   //===--------------------------------------------------------------------===//
 314   // Type Iteration support.
 315   //
 316   using subtype_iterator = Type * const *;
 317
 318   subtype_iterator subtype_begin() const { return ContainedTys; }
 319   subtype_iterator subtype_end() const { return &ContainedTys[NumContainedTys];}
 320   ArrayRef<Type*> subtypes() const {
 321     return makeArrayRef(subtype_begin(), subtype_end());
 322   }
 323
 324   using subtype_reverse_iterator = std::reverse_iterator<subtype_iterator>;
 325
 326   subtype_reverse_iterator subtype_rbegin() const {
 327     return subtype_reverse_iterator(subtype_end());
 328   }
 329   subtype_reverse_iterator subtype_rend() const {
 330     return subtype_reverse_iterator(subtype_begin());
 331   }
 332
 333   /// This method is used to implement the type iterator (defined at the end of
 334   /// the file). For derived types, this returns the types 'contained' in the
 335   /// derived type.
 336   Type *getContainedType(unsigned i) const {
 337     assert(i < NumContainedTys && "Index out of range!");
 338     return ContainedTys[i];
 339   }
 340
 341   /// Return the number of types in the derived type.
 342   unsigned getNumContainedTypes() const { return NumContainedTys; }
 343
 344   //===--------------------------------------------------------------------===//
 345   // Helper methods corresponding to subclass methods.  This forces a cast to
 346   // the specified subclass and calls its accessor.  "getVectorNumElements" (for
 347   // example) is shorthand for cast<VectorType>(Ty)->getNumElements().  This is
 348   // only intended to cover the core methods that are frequently used, helper
 349   // methods should not be added here.
 350
 351   inline unsigned getIntegerBitWidth() const;
 352
 353   inline Type *getFunctionParamType(unsigned i) const;
 354   inline unsigned getFunctionNumParams() const;
 355   inline bool isFunctionVarArg() const;
 356
 357   inline StringRef getStructName() const;
 358   inline unsigned getStructNumElements() const;
 359   inline Type *getStructElementType(unsigned N) const;
 360
 361   inline Type *getSequentialElementType() const {
 362     assert(isSequentialType(getTypeID()) && "Not a sequential type!");
 363     return ContainedTys[0];
 364   }
 365
 366   inline uint64_t getArrayNumElements() const;
 367
 368   Type *getArrayElementType() const {
 369     assert(getTypeID() == ArrayTyID);
 370     return ContainedTys[0];
 371   }
 372
 373   inline bool getVectorIsScalable() const;
 374   inline unsigned getVectorNumElements() const;
 375   inline ElementCount getVectorElementCount() const;
 376   Type *getVectorElementType() const {
 377     assert(getTypeID() == VectorTyID);
 378     return ContainedTys[0];
 379   }
 380
 381   Type *getPointerElementType() const {
 382     assert(getTypeID() == PointerTyID);
 383     return ContainedTys[0];
 384   }
 385
 386   /// Given an integer or vector type, change the lane bitwidth to NewBitwidth,
 387   /// whilst keeping the old number of lanes.
 388   inline Type *getWithNewBitWidth(unsigned NewBitWidth) const;
 389
 390   /// Given scalar/vector integer type, returns a type with elements twice as
 391   /// wide as in the original type. For vectors, preserves element count.
 392   inline Type *getExtendedType() const;
 393
 394   /// Get the address space of this pointer or pointer vector type.
 395   inline unsigned getPointerAddressSpace() const;
 396
 397   //===--------------------------------------------------------------------===//
 398   // Static members exported by the Type class itself.  Useful for getting
 399   // instances of Type.
 400   //
 401
 402   /// Return a type based on an identifier.
 403   static Type *getPrimitiveType(LLVMContext &C, TypeID IDNumber);
 404
 405   //===--------------------------------------------------------------------===//
 406   // These are the builtin types that are always available.
 407   //
 408   static Type *getVoidTy(LLVMContext &C);
 409   static Type *getLabelTy(LLVMContext &C);
 410   static Type *getHalfTy(LLVMContext &C);
 411   static Type *getFloatTy(LLVMContext &C);
 412   static Type *getDoubleTy(LLVMContext &C);
 413   static Type *getMetadataTy(LLVMContext &C);
 414   static Type *getX86_FP80Ty(LLVMContext &C);
 415   static Type *getFP128Ty(LLVMContext &C);
 416   static Type *getPPC_FP128Ty(LLVMContext &C);
 417   static Type *getX86_MMXTy(LLVMContext &C);
 418   static Type *getTokenTy(LLVMContext &C);
 419   static IntegerType *getIntNTy(LLVMContext &C, unsigned N);
 420   static IntegerType *getInt1Ty(LLVMContext &C);
 421   static IntegerType *getInt8Ty(LLVMContext &C);
 422   static IntegerType *getInt16Ty(LLVMContext &C);
 423   static IntegerType *getInt32Ty(LLVMContext &C);
 424   static IntegerType *getInt64Ty(LLVMContext &C);
 425   static IntegerType *getInt128Ty(LLVMContext &C);
 426   template <typename ScalarTy> static Type *getScalarTy(LLVMContext &C) {
 427     int noOfBits = sizeof(ScalarTy) * CHAR_BIT;
 428     if (std::is_integral<ScalarTy>::value) {
 429       return (Type*) Type::getIntNTy(C, noOfBits);
 430     } else if (std::is_floating_point<ScalarTy>::value) {
 431       switch (noOfBits) {
 432       case 32:
 433         return Type::getFloatTy(C);
 434       case 64:
 435         return Type::getDoubleTy(C);
 436       }
 437     }
 438     llvm_unreachable("Unsupported type in Type::getScalarTy");
 439   }
 440
 441   //===--------------------------------------------------------------------===//
 442   // Convenience methods for getting pointer types with one of the above builtin
 443   // types as pointee.
 444   //
 445   static PointerType *getHalfPtrTy(LLVMContext &C, unsigned AS = 0);
 446   static PointerType *getFloatPtrTy(LLVMContext &C, unsigned AS = 0);
 447   static PointerType *getDoublePtrTy(LLVMContext &C, unsigned AS = 0);
 448   static PointerType *getX86_FP80PtrTy(LLVMContext &C, unsigned AS = 0);
 449   static PointerType *getFP128PtrTy(LLVMContext &C, unsigned AS = 0);
 450   static PointerType *getPPC_FP128PtrTy(LLVMContext &C, unsigned AS = 0);
 451   static PointerType *getX86_MMXPtrTy(LLVMContext &C, unsigned AS = 0);
 452   static PointerType *getIntNPtrTy(LLVMContext &C, unsigned N, unsigned AS = 0);
 453   static PointerType *getInt1PtrTy(LLVMContext &C, unsigned AS = 0);
 454   static PointerType *getInt8PtrTy(LLVMContext &C, unsigned AS = 0);
 455   static PointerType *getInt16PtrTy(LLVMContext &C, unsigned AS = 0);
 456   static PointerType *getInt32PtrTy(LLVMContext &C, unsigned AS = 0);
 457   static PointerType *getInt64PtrTy(LLVMContext &C, unsigned AS = 0);
 458
 459   /// Return a pointer to the current type. This is equivalent to
 460   /// PointerType::get(Foo, AddrSpace).
 461   PointerType *getPointerTo(unsigned AddrSpace = 0) const;
 462
 463 private:
 464   /// Derived types like structures and arrays are sized iff all of the members
 465   /// of the type are sized as well. Since asking for their size is relatively
 466   /// uncommon, move this operation out-of-line.
 467   bool isSizedDerivedType(SmallPtrSetImpl<Type*> *Visited = nullptr) const;
 468 };
 469
 470 // Printing of types.
 471 inline raw_ostream &operator<<(raw_ostream &OS, const Type &T) {
 472   T.print(OS);
 473   return OS;
 474 }
 475
 476 // allow isa<PointerType>(x) to work without DerivedTypes.h included.
 477 template <> struct isa_impl<PointerType, Type> {
 478   static inline bool doit(const Type &Ty) {
 479     return Ty.getTypeID() == Type::PointerTyID;
 480   }
 481 };
 482
 483 // Create wrappers for C Binding types (see CBindingWrapping.h).
 484 DEFINE_ISA_CONVERSION_FUNCTIONS(Type, LLVMTypeRef)
 485
 486 /* Specialized opaque type conversions.
 487  */
 488 inline Type **unwrap(LLVMTypeRef* Tys) {
 489   return reinterpret_cast<Type**>(Tys);
 490 }
 491
 492 inline LLVMTypeRef *wrap(Type **Tys) {
 493   return reinterpret_cast<LLVMTypeRef*>(const_cast<Type**>(Tys));
 494 }
 495
 496 } // end namespace llvm
 497
 498 #endif // LLVM_IR_TYPE_H