Type.h revision de2d8694e25a814696358e95141f4b1aa4d8847e 
1//===-- llvm/Type.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 declaration of the Type class.  For more "Type"
11// stuff, look in DerivedTypes.h.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_IR_TYPE_H
16#define LLVM_IR_TYPE_H
17
18#include "llvm/ADT/APFloat.h"
19#include "llvm/ADT/ArrayRef.h"
20#include "llvm/ADT/SmallPtrSet.h"
21#include "llvm/Support/CBindingWrapping.h"
22#include "llvm/Support/Casting.h"
23#include "llvm/Support/DataTypes.h"
24#include "llvm/Support/ErrorHandling.h"
25
26namespace llvm {
27
28class PointerType;
29class IntegerType;
30class raw_ostream;
31class Module;
32class LLVMContext;
33class LLVMContextImpl;
34class StringRef;
35template<class GraphType> struct GraphTraits;
36
37/// The instances of the Type class are immutable: once they are created,
38/// they are never changed.  Also note that only one instance of a particular
39/// type is ever created.  Thus seeing if two types are equal is a matter of
40/// doing a trivial pointer comparison. To enforce that no two equal instances
41/// are created, Type instances can only be created via static factory methods
42/// in class Type and in derived classes.  Once allocated, Types are never
43/// free'd.
44///
45class Type {
46public:
47  //===--------------------------------------------------------------------===//
48  /// Definitions of all of the base types for the Type system.  Based on this
49  /// value, you can cast to a class defined in DerivedTypes.h.
50  /// Note: If you add an element to this, you need to add an element to the
51  /// Type::getPrimitiveType function, or else things will break!
52  /// Also update LLVMTypeKind and LLVMGetTypeKind () in the C binding.
53  ///
54  enum TypeID {
55    // PrimitiveTypes - make sure LastPrimitiveTyID stays up to date.
56    VoidTyID = 0,    ///<  0: type with no size
57    HalfTyID,        ///<  1: 16-bit floating point type
58    FloatTyID,       ///<  2: 32-bit floating point type
59    DoubleTyID,      ///<  3: 64-bit floating point type
60    X86_FP80TyID,    ///<  4: 80-bit floating point type (X87)
61    FP128TyID,       ///<  5: 128-bit floating point type (112-bit mantissa)
62    PPC_FP128TyID,   ///<  6: 128-bit floating point type (two 64-bits, PowerPC)
63    LabelTyID,       ///<  7: Labels
64    MetadataTyID,    ///<  8: Metadata
65    X86_MMXTyID,     ///<  9: MMX vectors (64 bits, X86 specific)
66    TokenTyID,       ///< 10: Tokens
67
68    // Derived types... see DerivedTypes.h file.
69    // Make sure FirstDerivedTyID stays up to date!
70    IntegerTyID,     ///< 11: Arbitrary bit width integers
71    FunctionTyID,    ///< 12: Functions
72    StructTyID,      ///< 13: Structures
73    ArrayTyID,       ///< 14: Arrays
74    PointerTyID,     ///< 15: Pointers
75    VectorTyID       ///< 16: SIMD 'packed' format, or other vector type
76  };
77
78private:
79  /// This refers to the LLVMContext in which this type was uniqued.
80  LLVMContext &Context;
81
82  TypeID   ID : 8;            // The current base type of this type.
83  unsigned SubclassData : 24; // Space for subclasses to store data.
84
85protected:
86  friend class LLVMContextImpl;
87  explicit Type(LLVMContext &C, TypeID tid)
88    : Context(C), ID(tid), SubclassData(0),
89      NumContainedTys(0), ContainedTys(nullptr) {}
90  ~Type() = default;
91
92  unsigned getSubclassData() const { return SubclassData; }
93
94  void setSubclassData(unsigned val) {
95    SubclassData = val;
96    // Ensure we don't have any accidental truncation.
97    assert(getSubclassData() == val && "Subclass data too large for field");
98  }
99
100  /// Keeps track of how many Type*'s there are in the ContainedTys list.
101  unsigned NumContainedTys;
102
103  /// A pointer to the array of Types contained by this Type. For example, this
104  /// includes the arguments of a function type, the elements of a structure,
105  /// the pointee of a pointer, the element type of an array, etc. This pointer
106  /// may be 0 for types that don't contain other types (Integer, Double,
107  /// Float).
108  Type * const *ContainedTys;
109
110  static bool isSequentialType(TypeID TyID) {
111    return TyID == ArrayTyID || TyID == PointerTyID || TyID == VectorTyID;
112  }
113
114public:
115  /// Print the current type.
116  /// Omit the type details if \p NoDetails == true.
117  /// E.g., let %st = type { i32, i16 }
118  /// When \p NoDetails is true, we only print %st.
119  /// Put differently, \p NoDetails prints the type as if
120  /// inlined with the operands when printing an instruction.
121  void print(raw_ostream &O, bool IsForDebug = false,
122             bool NoDetails = false) const;
123  void dump() const;
124
125  /// Return the LLVMContext in which this type was uniqued.
126  LLVMContext &getContext() const { return Context; }
127
128  //===--------------------------------------------------------------------===//
129  // Accessors for working with types.
130  //
131
132  /// Return the type id for the type. This will return one of the TypeID enum
133  /// elements defined above.
134  TypeID getTypeID() const { return ID; }
135
136  /// Return true if this is 'void'.
137  bool isVoidTy() const { return getTypeID() == VoidTyID; }
138
139  /// Return true if this is 'half', a 16-bit IEEE fp type.
140  bool isHalfTy() const { return getTypeID() == HalfTyID; }
141
142  /// Return true if this is 'float', a 32-bit IEEE fp type.
143  bool isFloatTy() const { return getTypeID() == FloatTyID; }
144
145  /// Return true if this is 'double', a 64-bit IEEE fp type.
146  bool isDoubleTy() const { return getTypeID() == DoubleTyID; }
147
148  /// Return true if this is x86 long double.
149  bool isX86_FP80Ty() const { return getTypeID() == X86_FP80TyID; }
150
151  /// Return true if this is 'fp128'.
152  bool isFP128Ty() const { return getTypeID() == FP128TyID; }
153
154  /// Return true if this is powerpc long double.
155  bool isPPC_FP128Ty() const { return getTypeID() == PPC_FP128TyID; }
156
157  /// Return true if this is one of the six floating-point types
158  bool isFloatingPointTy() const {
159    return getTypeID() == HalfTyID || getTypeID() == FloatTyID ||
160           getTypeID() == DoubleTyID ||
161           getTypeID() == X86_FP80TyID || getTypeID() == FP128TyID ||
162           getTypeID() == PPC_FP128TyID;
163  }
164
165  const fltSemantics &getFltSemantics() const {
166    switch (getTypeID()) {
167    case HalfTyID: return APFloat::IEEEhalf;
168    case FloatTyID: return APFloat::IEEEsingle;
169    case DoubleTyID: return APFloat::IEEEdouble;
170    case X86_FP80TyID: return APFloat::x87DoubleExtended;
171    case FP128TyID: return APFloat::IEEEquad;
172    case PPC_FP128TyID: return APFloat::PPCDoubleDouble;
173    default: llvm_unreachable("Invalid floating type");
174    }
175  }
176
177  /// Return true if this is X86 MMX.
178  bool isX86_MMXTy() const { return getTypeID() == X86_MMXTyID; }
179
180  /// Return true if this is a FP type or a vector of FP.
181  bool isFPOrFPVectorTy() const { return getScalarType()->isFloatingPointTy(); }
182
183  /// Return true if this is 'label'.
184  bool isLabelTy() const { return getTypeID() == LabelTyID; }
185
186  /// Return true if this is 'metadata'.
187  bool isMetadataTy() const { return getTypeID() == MetadataTyID; }
188
189  /// Return true if this is 'token'.
190  bool isTokenTy() const { return getTypeID() == TokenTyID; }
191
192  /// True if this is an instance of IntegerType.
193  bool isIntegerTy() const { return getTypeID() == IntegerTyID; }
194
195  /// Return true if this is an IntegerType of the given width.
196  bool isIntegerTy(unsigned Bitwidth) const;
197
198  /// Return true if this is an integer type or a vector of integer types.
199  bool isIntOrIntVectorTy() const { return getScalarType()->isIntegerTy(); }
200
201  /// True if this is an instance of FunctionType.
202  bool isFunctionTy() const { return getTypeID() == FunctionTyID; }
203
204  /// True if this is an instance of StructType.
205  bool isStructTy() const { return getTypeID() == StructTyID; }
206
207  /// True if this is an instance of ArrayType.
208  bool isArrayTy() const { return getTypeID() == ArrayTyID; }
209
210  /// True if this is an instance of PointerType.
211  bool isPointerTy() const { return getTypeID() == PointerTyID; }
212
213  /// Return true if this is a pointer type or a vector of pointer types.
214  bool isPtrOrPtrVectorTy() const { return getScalarType()->isPointerTy(); }
215
216  /// True if this is an instance of VectorType.
217  bool isVectorTy() const { return getTypeID() == VectorTyID; }
218
219  /// Return true if this type could be converted with a lossless BitCast to
220  /// type 'Ty'. For example, i8* to i32*. BitCasts are valid for types of the
221  /// same size only where no re-interpretation of the bits is done.
222  /// @brief Determine if this type could be losslessly bitcast to Ty
223  bool canLosslesslyBitCastTo(Type *Ty) const;
224
225  /// Return true if this type is empty, that is, it has no elements or all of
226  /// its elements are empty.
227  bool isEmptyTy() const;
228
229  /// Return true if the type is "first class", meaning it is a valid type for a
230  /// Value.
231  bool isFirstClassType() const {
232    return getTypeID() != FunctionTyID && getTypeID() != VoidTyID;
233  }
234
235  /// Return true if the type is a valid type for a register in codegen. This
236  /// includes all first-class types except struct and array types.
237  bool isSingleValueType() const {
238    return isFloatingPointTy() || isX86_MMXTy() || isIntegerTy() ||
239           isPointerTy() || isVectorTy();
240  }
241
242  /// Return true if the type is an aggregate type. This means it is valid as
243  /// the first operand of an insertvalue or extractvalue instruction. This
244  /// includes struct and array types, but does not include vector types.
245  bool isAggregateType() const {
246    return getTypeID() == StructTyID || getTypeID() == ArrayTyID;
247  }
248
249  /// Return true if it makes sense to take the size of this type. To get the
250  /// actual size for a particular target, it is reasonable to use the
251  /// DataLayout subsystem to do this.
252  bool isSized(SmallPtrSetImpl<Type*> *Visited = nullptr) const {
253    // If it's a primitive, it is always sized.
254    if (getTypeID() == IntegerTyID || isFloatingPointTy() ||
255        getTypeID() == PointerTyID ||
256        getTypeID() == X86_MMXTyID)
257      return true;
258    // If it is not something that can have a size (e.g. a function or label),
259    // it doesn't have a size.
260    if (getTypeID() != StructTyID && getTypeID() != ArrayTyID &&
261        getTypeID() != VectorTyID)
262      return false;
263    // Otherwise we have to try harder to decide.
264    return isSizedDerivedType(Visited);
265  }
266
267  /// Return the basic size of this type if it is a primitive type. These are
268  /// fixed by LLVM and are not target-dependent.
269  /// This will return zero if the type does not have a size or is not a
270  /// primitive type.
271  ///
272  /// Note that this may not reflect the size of memory allocated for an
273  /// instance of the type or the number of bytes that are written when an
274  /// instance of the type is stored to memory. The DataLayout class provides
275  /// additional query functions to provide this information.
276  ///
277  unsigned getPrimitiveSizeInBits() const LLVM_READONLY;
278
279  /// If this is a vector type, return the getPrimitiveSizeInBits value for the
280  /// element type. Otherwise return the getPrimitiveSizeInBits value for this
281  /// type.
282  unsigned getScalarSizeInBits() const LLVM_READONLY;
283
284  /// Return the width of the mantissa of this type. This is only valid on
285  /// floating-point types. If the FP type does not have a stable mantissa (e.g.
286  /// ppc long double), this method returns -1.
287  int getFPMantissaWidth() const;
288
289  /// If this is a vector type, return the element type, otherwise return
290  /// 'this'.
291  Type *getScalarType() const LLVM_READONLY;
292
293  //===--------------------------------------------------------------------===//
294  // Type Iteration support.
295  //
296  typedef Type * const *subtype_iterator;
297  subtype_iterator subtype_begin() const { return ContainedTys; }
298  subtype_iterator subtype_end() const { return &ContainedTys[NumContainedTys];}
299  ArrayRef<Type*> subtypes() const {
300    return makeArrayRef(subtype_begin(), subtype_end());
301  }
302
303  typedef std::reverse_iterator<subtype_iterator> subtype_reverse_iterator;
304  subtype_reverse_iterator subtype_rbegin() const {
305    return subtype_reverse_iterator(subtype_end());
306  }
307  subtype_reverse_iterator subtype_rend() const {
308    return subtype_reverse_iterator(subtype_begin());
309  }
310
311  /// This method is used to implement the type iterator (defined at the end of
312  /// the file). For derived types, this returns the types 'contained' in the
313  /// derived type.
314  Type *getContainedType(unsigned i) const {
315    assert(i < NumContainedTys && "Index out of range!");
316    return ContainedTys[i];
317  }
318
319  /// Return the number of types in the derived type.
320  unsigned getNumContainedTypes() const { return NumContainedTys; }
321
322  //===--------------------------------------------------------------------===//
323  // Helper methods corresponding to subclass methods.  This forces a cast to
324  // the specified subclass and calls its accessor.  "getVectorNumElements" (for
325  // example) is shorthand for cast<VectorType>(Ty)->getNumElements().  This is
326  // only intended to cover the core methods that are frequently used, helper
327  // methods should not be added here.
328
329  inline unsigned getIntegerBitWidth() const;
330
331  inline Type *getFunctionParamType(unsigned i) const;
332  inline unsigned getFunctionNumParams() const;
333  inline bool isFunctionVarArg() const;
334
335  inline StringRef getStructName() const;
336  inline unsigned getStructNumElements() const;
337  inline Type *getStructElementType(unsigned N) const;
338
339  inline Type *getSequentialElementType() const {
340    assert(isSequentialType(getTypeID()) && "Not a sequential type!");
341    return ContainedTys[0];
342  }
343
344  inline uint64_t getArrayNumElements() const;
345  Type *getArrayElementType() const { return getSequentialElementType(); }
346
347  inline unsigned getVectorNumElements() const;
348  Type *getVectorElementType() const { return getSequentialElementType(); }
349
350  Type *getPointerElementType() const { return getSequentialElementType(); }
351
352  /// Get the address space of this pointer or pointer vector type.
353  inline unsigned getPointerAddressSpace() const;
354
355  //===--------------------------------------------------------------------===//
356  // Static members exported by the Type class itself.  Useful for getting
357  // instances of Type.
358  //
359
360  /// Return a type based on an identifier.
361  static Type *getPrimitiveType(LLVMContext &C, TypeID IDNumber);
362
363  //===--------------------------------------------------------------------===//
364  // These are the builtin types that are always available.
365  //
366  static Type *getVoidTy(LLVMContext &C);
367  static Type *getLabelTy(LLVMContext &C);
368  static Type *getHalfTy(LLVMContext &C);
369  static Type *getFloatTy(LLVMContext &C);
370  static Type *getDoubleTy(LLVMContext &C);
371  static Type *getMetadataTy(LLVMContext &C);
372  static Type *getX86_FP80Ty(LLVMContext &C);
373  static Type *getFP128Ty(LLVMContext &C);
374  static Type *getPPC_FP128Ty(LLVMContext &C);
375  static Type *getX86_MMXTy(LLVMContext &C);
376  static Type *getTokenTy(LLVMContext &C);
377  static IntegerType *getIntNTy(LLVMContext &C, unsigned N);
378  static IntegerType *getInt1Ty(LLVMContext &C);
379  static IntegerType *getInt8Ty(LLVMContext &C);
380  static IntegerType *getInt16Ty(LLVMContext &C);
381  static IntegerType *getInt32Ty(LLVMContext &C);
382  static IntegerType *getInt64Ty(LLVMContext &C);
383  static IntegerType *getInt128Ty(LLVMContext &C);
384
385  //===--------------------------------------------------------------------===//
386  // Convenience methods for getting pointer types with one of the above builtin
387  // types as pointee.
388  //
389  static PointerType *getHalfPtrTy(LLVMContext &C, unsigned AS = 0);
390  static PointerType *getFloatPtrTy(LLVMContext &C, unsigned AS = 0);
391  static PointerType *getDoublePtrTy(LLVMContext &C, unsigned AS = 0);
392  static PointerType *getX86_FP80PtrTy(LLVMContext &C, unsigned AS = 0);
393  static PointerType *getFP128PtrTy(LLVMContext &C, unsigned AS = 0);
394  static PointerType *getPPC_FP128PtrTy(LLVMContext &C, unsigned AS = 0);
395  static PointerType *getX86_MMXPtrTy(LLVMContext &C, unsigned AS = 0);
396  static PointerType *getIntNPtrTy(LLVMContext &C, unsigned N, unsigned AS = 0);
397  static PointerType *getInt1PtrTy(LLVMContext &C, unsigned AS = 0);
398  static PointerType *getInt8PtrTy(LLVMContext &C, unsigned AS = 0);
399  static PointerType *getInt16PtrTy(LLVMContext &C, unsigned AS = 0);
400  static PointerType *getInt32PtrTy(LLVMContext &C, unsigned AS = 0);
401  static PointerType *getInt64PtrTy(LLVMContext &C, unsigned AS = 0);
402
403  /// Return a pointer to the current type. This is equivalent to
404  /// PointerType::get(Foo, AddrSpace).
405  PointerType *getPointerTo(unsigned AddrSpace = 0) const;
406
407private:
408  /// Derived types like structures and arrays are sized iff all of the members
409  /// of the type are sized as well. Since asking for their size is relatively
410  /// uncommon, move this operation out-of-line.
411  bool isSizedDerivedType(SmallPtrSetImpl<Type*> *Visited = nullptr) const;
412};
413
414// Printing of types.
415static inline raw_ostream &operator<<(raw_ostream &OS, Type &T) {
416  T.print(OS);
417  return OS;
418}
419
420// allow isa<PointerType>(x) to work without DerivedTypes.h included.
421template <> struct isa_impl<PointerType, Type> {
422  static inline bool doit(const Type &Ty) {
423    return Ty.getTypeID() == Type::PointerTyID;
424  }
425};
426
427//===----------------------------------------------------------------------===//
428// Provide specializations of GraphTraits to be able to treat a type as a
429// graph of sub types.
430
431template <> struct GraphTraits<Type *> {
432  typedef Type NodeType;
433  typedef Type::subtype_iterator ChildIteratorType;
434
435  static inline NodeType *getEntryNode(Type *T) { return T; }
436  static inline ChildIteratorType child_begin(NodeType *N) {
437    return N->subtype_begin();
438  }
439  static inline ChildIteratorType child_end(NodeType *N) {
440    return N->subtype_end();
441  }
442};
443
444template <> struct GraphTraits<const Type*> {
445  typedef const Type NodeType;
446  typedef Type::subtype_iterator ChildIteratorType;
447
448  static inline NodeType *getEntryNode(NodeType *T) { return T; }
449  static inline ChildIteratorType child_begin(NodeType *N) {
450    return N->subtype_begin();
451  }
452  static inline ChildIteratorType child_end(NodeType *N) {
453    return N->subtype_end();
454  }
455};
456
457// Create wrappers for C Binding types (see CBindingWrapping.h).
458DEFINE_ISA_CONVERSION_FUNCTIONS(Type, LLVMTypeRef)
459
460/* Specialized opaque type conversions.
461 */
462inline Type **unwrap(LLVMTypeRef* Tys) {
463  return reinterpret_cast<Type**>(Tys);
464}
465
466inline LLVMTypeRef *wrap(Type **Tys) {
467  return reinterpret_cast<LLVMTypeRef*>(const_cast<Type**>(Tys));
468}
469
470} // End llvm namespace
471
472#endif
473