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                              // Note that this should be synchronized with
85                              // MAX_INT_BITS value in IntegerType class.
86
87protected:
88  friend class LLVMContextImpl;
89  explicit Type(LLVMContext &C, TypeID tid)
90    : Context(C), ID(tid), SubclassData(0),
91      NumContainedTys(0), ContainedTys(nullptr) {}
92  ~Type() = default;
93
94  unsigned getSubclassData() const { return SubclassData; }
95
96  void setSubclassData(unsigned val) {
97    SubclassData = val;
98    // Ensure we don't have any accidental truncation.
99    assert(getSubclassData() == val && "Subclass data too large for field");
100  }
101
102  /// Keeps track of how many Type*'s there are in the ContainedTys list.
103  unsigned NumContainedTys;
104
105  /// A pointer to the array of Types contained by this Type. For example, this
106  /// includes the arguments of a function type, the elements of a structure,
107  /// the pointee of a pointer, the element type of an array, etc. This pointer
108  /// may be 0 for types that don't contain other types (Integer, Double,
109  /// Float).
110  Type * const *ContainedTys;
111
112  static bool isSequentialType(TypeID TyID) {
113    return TyID == ArrayTyID || TyID == VectorTyID;
114  }
115
116public:
117  /// Print the current type.
118  /// Omit the type details if \p NoDetails == true.
119  /// E.g., let %st = type { i32, i16 }
120  /// When \p NoDetails is true, we only print %st.
121  /// Put differently, \p NoDetails prints the type as if
122  /// inlined with the operands when printing an instruction.
123  void print(raw_ostream &O, bool IsForDebug = false,
124             bool NoDetails = false) const;
125  void dump() const;
126
127  /// Return the LLVMContext in which this type was uniqued.
128  LLVMContext &getContext() const { return Context; }
129
130  //===--------------------------------------------------------------------===//
131  // Accessors for working with types.
132  //
133
134  /// Return the type id for the type. This will return one of the TypeID enum
135  /// elements defined above.
136  TypeID getTypeID() const { return ID; }
137
138  /// Return true if this is 'void'.
139  bool isVoidTy() const { return getTypeID() == VoidTyID; }
140
141  /// Return true if this is 'half', a 16-bit IEEE fp type.
142  bool isHalfTy() const { return getTypeID() == HalfTyID; }
143
144  /// Return true if this is 'float', a 32-bit IEEE fp type.
145  bool isFloatTy() const { return getTypeID() == FloatTyID; }
146
147  /// Return true if this is 'double', a 64-bit IEEE fp type.
148  bool isDoubleTy() const { return getTypeID() == DoubleTyID; }
149
150  /// Return true if this is x86 long double.
151  bool isX86_FP80Ty() const { return getTypeID() == X86_FP80TyID; }
152
153  /// Return true if this is 'fp128'.
154  bool isFP128Ty() const { return getTypeID() == FP128TyID; }
155
156  /// Return true if this is powerpc long double.
157  bool isPPC_FP128Ty() const { return getTypeID() == PPC_FP128TyID; }
158
159  /// Return true if this is one of the six floating-point types
160  bool isFloatingPointTy() const {
161    return getTypeID() == HalfTyID || getTypeID() == FloatTyID ||
162           getTypeID() == DoubleTyID ||
163           getTypeID() == X86_FP80TyID || getTypeID() == FP128TyID ||
164           getTypeID() == PPC_FP128TyID;
165  }
166
167  const fltSemantics &getFltSemantics() const {
168    switch (getTypeID()) {
169    case HalfTyID: return APFloat::IEEEhalf();
170    case FloatTyID: return APFloat::IEEEsingle();
171    case DoubleTyID: return APFloat::IEEEdouble();
172    case X86_FP80TyID: return APFloat::x87DoubleExtended();
173    case FP128TyID: return APFloat::IEEEquad();
174    case PPC_FP128TyID: return APFloat::PPCDoubleDouble();
175    default: llvm_unreachable("Invalid floating type");
176    }
177  }
178
179  /// Return true if this is X86 MMX.
180  bool isX86_MMXTy() const { return getTypeID() == X86_MMXTyID; }
181
182  /// Return true if this is a FP type or a vector of FP.
183  bool isFPOrFPVectorTy() const { return getScalarType()->isFloatingPointTy(); }
184
185  /// Return true if this is 'label'.
186  bool isLabelTy() const { return getTypeID() == LabelTyID; }
187
188  /// Return true if this is 'metadata'.
189  bool isMetadataTy() const { return getTypeID() == MetadataTyID; }
190
191  /// Return true if this is 'token'.
192  bool isTokenTy() const { return getTypeID() == TokenTyID; }
193
194  /// True if this is an instance of IntegerType.
195  bool isIntegerTy() const { return getTypeID() == IntegerTyID; }
196
197  /// Return true if this is an IntegerType of the given width.
198  bool isIntegerTy(unsigned Bitwidth) const;
199
200  /// Return true if this is an integer type or a vector of integer types.
201  bool isIntOrIntVectorTy() const { return getScalarType()->isIntegerTy(); }
202
203  /// True if this is an instance of FunctionType.
204  bool isFunctionTy() const { return getTypeID() == FunctionTyID; }
205
206  /// True if this is an instance of StructType.
207  bool isStructTy() const { return getTypeID() == StructTyID; }
208
209  /// True if this is an instance of ArrayType.
210  bool isArrayTy() const { return getTypeID() == ArrayTyID; }
211
212  /// True if this is an instance of PointerType.
213  bool isPointerTy() const { return getTypeID() == PointerTyID; }
214
215  /// Return true if this is a pointer type or a vector of pointer types.
216  bool isPtrOrPtrVectorTy() const { return getScalarType()->isPointerTy(); }
217
218  /// True if this is an instance of VectorType.
219  bool isVectorTy() const { return getTypeID() == VectorTyID; }
220
221  /// Return true if this type could be converted with a lossless BitCast to
222  /// type 'Ty'. For example, i8* to i32*. BitCasts are valid for types of the
223  /// same size only where no re-interpretation of the bits is done.
224  /// @brief Determine if this type could be losslessly bitcast to Ty
225  bool canLosslesslyBitCastTo(Type *Ty) const;
226
227  /// Return true if this type is empty, that is, it has no elements or all of
228  /// its elements are empty.
229  bool isEmptyTy() const;
230
231  /// Return true if the type is "first class", meaning it is a valid type for a
232  /// Value.
233  bool isFirstClassType() const {
234    return getTypeID() != FunctionTyID && getTypeID() != VoidTyID;
235  }
236
237  /// Return true if the type is a valid type for a register in codegen. This
238  /// includes all first-class types except struct and array types.
239  bool isSingleValueType() const {
240    return isFloatingPointTy() || isX86_MMXTy() || isIntegerTy() ||
241           isPointerTy() || isVectorTy();
242  }
243
244  /// Return true if the type is an aggregate type. This means it is valid as
245  /// the first operand of an insertvalue or extractvalue instruction. This
246  /// includes struct and array types, but does not include vector types.
247  bool isAggregateType() const {
248    return getTypeID() == StructTyID || getTypeID() == ArrayTyID;
249  }
250
251  /// Return true if it makes sense to take the size of this type. To get the
252  /// actual size for a particular target, it is reasonable to use the
253  /// DataLayout subsystem to do this.
254  bool isSized(SmallPtrSetImpl<Type*> *Visited = nullptr) const {
255    // If it's a primitive, it is always sized.
256    if (getTypeID() == IntegerTyID || isFloatingPointTy() ||
257        getTypeID() == PointerTyID ||
258        getTypeID() == X86_MMXTyID)
259      return true;
260    // If it is not something that can have a size (e.g. a function or label),
261    // it doesn't have a size.
262    if (getTypeID() != StructTyID && getTypeID() != ArrayTyID &&
263        getTypeID() != VectorTyID)
264      return false;
265    // Otherwise we have to try harder to decide.
266    return isSizedDerivedType(Visited);
267  }
268
269  /// Return the basic size of this type if it is a primitive type. These are
270  /// fixed by LLVM and are not target-dependent.
271  /// This will return zero if the type does not have a size or is not a
272  /// primitive type.
273  ///
274  /// Note that this may not reflect the size of memory allocated for an
275  /// instance of the type or the number of bytes that are written when an
276  /// instance of the type is stored to memory. The DataLayout class provides
277  /// additional query functions to provide this information.
278  ///
279  unsigned getPrimitiveSizeInBits() const LLVM_READONLY;
280
281  /// If this is a vector type, return the getPrimitiveSizeInBits value for the
282  /// element type. Otherwise return the getPrimitiveSizeInBits value for this
283  /// type.
284  unsigned getScalarSizeInBits() const LLVM_READONLY;
285
286  /// Return the width of the mantissa of this type. This is only valid on
287  /// floating-point types. If the FP type does not have a stable mantissa (e.g.
288  /// ppc long double), this method returns -1.
289  int getFPMantissaWidth() const;
290
291  /// If this is a vector type, return the element type, otherwise return
292  /// 'this'.
293  Type *getScalarType() const LLVM_READONLY;
294
295  //===--------------------------------------------------------------------===//
296  // Type Iteration support.
297  //
298  typedef Type * const *subtype_iterator;
299  subtype_iterator subtype_begin() const { return ContainedTys; }
300  subtype_iterator subtype_end() const { return &ContainedTys[NumContainedTys];}
301  ArrayRef<Type*> subtypes() const {
302    return makeArrayRef(subtype_begin(), subtype_end());
303  }
304
305  typedef std::reverse_iterator<subtype_iterator> subtype_reverse_iterator;
306  subtype_reverse_iterator subtype_rbegin() const {
307    return subtype_reverse_iterator(subtype_end());
308  }
309  subtype_reverse_iterator subtype_rend() const {
310    return subtype_reverse_iterator(subtype_begin());
311  }
312
313  /// This method is used to implement the type iterator (defined at the end of
314  /// the file). For derived types, this returns the types 'contained' in the
315  /// derived type.
316  Type *getContainedType(unsigned i) const {
317    assert(i < NumContainedTys && "Index out of range!");
318    return ContainedTys[i];
319  }
320
321  /// Return the number of types in the derived type.
322  unsigned getNumContainedTypes() const { return NumContainedTys; }
323
324  //===--------------------------------------------------------------------===//
325  // Helper methods corresponding to subclass methods.  This forces a cast to
326  // the specified subclass and calls its accessor.  "getVectorNumElements" (for
327  // example) is shorthand for cast<VectorType>(Ty)->getNumElements().  This is
328  // only intended to cover the core methods that are frequently used, helper
329  // methods should not be added here.
330
331  inline unsigned getIntegerBitWidth() const;
332
333  inline Type *getFunctionParamType(unsigned i) const;
334  inline unsigned getFunctionNumParams() const;
335  inline bool isFunctionVarArg() const;
336
337  inline StringRef getStructName() const;
338  inline unsigned getStructNumElements() const;
339  inline Type *getStructElementType(unsigned N) const;
340
341  inline Type *getSequentialElementType() const {
342    assert(isSequentialType(getTypeID()) && "Not a sequential type!");
343    return ContainedTys[0];
344  }
345
346  inline uint64_t getArrayNumElements() const;
347  Type *getArrayElementType() const {
348    assert(getTypeID() == ArrayTyID);
349    return ContainedTys[0];
350  }
351
352  inline unsigned getVectorNumElements() const;
353  Type *getVectorElementType() const {
354    assert(getTypeID() == VectorTyID);
355    return ContainedTys[0];
356  }
357
358  Type *getPointerElementType() const {
359    assert(getTypeID() == PointerTyID);
360    return ContainedTys[0];
361  }
362
363  /// Get the address space of this pointer or pointer vector type.
364  inline unsigned getPointerAddressSpace() const;
365
366  //===--------------------------------------------------------------------===//
367  // Static members exported by the Type class itself.  Useful for getting
368  // instances of Type.
369  //
370
371  /// Return a type based on an identifier.
372  static Type *getPrimitiveType(LLVMContext &C, TypeID IDNumber);
373
374  //===--------------------------------------------------------------------===//
375  // These are the builtin types that are always available.
376  //
377  static Type *getVoidTy(LLVMContext &C);
378  static Type *getLabelTy(LLVMContext &C);
379  static Type *getHalfTy(LLVMContext &C);
380  static Type *getFloatTy(LLVMContext &C);
381  static Type *getDoubleTy(LLVMContext &C);
382  static Type *getMetadataTy(LLVMContext &C);
383  static Type *getX86_FP80Ty(LLVMContext &C);
384  static Type *getFP128Ty(LLVMContext &C);
385  static Type *getPPC_FP128Ty(LLVMContext &C);
386  static Type *getX86_MMXTy(LLVMContext &C);
387  static Type *getTokenTy(LLVMContext &C);
388  static IntegerType *getIntNTy(LLVMContext &C, unsigned N);
389  static IntegerType *getInt1Ty(LLVMContext &C);
390  static IntegerType *getInt8Ty(LLVMContext &C);
391  static IntegerType *getInt16Ty(LLVMContext &C);
392  static IntegerType *getInt32Ty(LLVMContext &C);
393  static IntegerType *getInt64Ty(LLVMContext &C);
394  static IntegerType *getInt128Ty(LLVMContext &C);
395
396  //===--------------------------------------------------------------------===//
397  // Convenience methods for getting pointer types with one of the above builtin
398  // types as pointee.
399  //
400  static PointerType *getHalfPtrTy(LLVMContext &C, unsigned AS = 0);
401  static PointerType *getFloatPtrTy(LLVMContext &C, unsigned AS = 0);
402  static PointerType *getDoublePtrTy(LLVMContext &C, unsigned AS = 0);
403  static PointerType *getX86_FP80PtrTy(LLVMContext &C, unsigned AS = 0);
404  static PointerType *getFP128PtrTy(LLVMContext &C, unsigned AS = 0);
405  static PointerType *getPPC_FP128PtrTy(LLVMContext &C, unsigned AS = 0);
406  static PointerType *getX86_MMXPtrTy(LLVMContext &C, unsigned AS = 0);
407  static PointerType *getIntNPtrTy(LLVMContext &C, unsigned N, unsigned AS = 0);
408  static PointerType *getInt1PtrTy(LLVMContext &C, unsigned AS = 0);
409  static PointerType *getInt8PtrTy(LLVMContext &C, unsigned AS = 0);
410  static PointerType *getInt16PtrTy(LLVMContext &C, unsigned AS = 0);
411  static PointerType *getInt32PtrTy(LLVMContext &C, unsigned AS = 0);
412  static PointerType *getInt64PtrTy(LLVMContext &C, unsigned AS = 0);
413
414  /// Return a pointer to the current type. This is equivalent to
415  /// PointerType::get(Foo, AddrSpace).
416  PointerType *getPointerTo(unsigned AddrSpace = 0) const;
417
418private:
419  /// Derived types like structures and arrays are sized iff all of the members
420  /// of the type are sized as well. Since asking for their size is relatively
421  /// uncommon, move this operation out-of-line.
422  bool isSizedDerivedType(SmallPtrSetImpl<Type*> *Visited = nullptr) const;
423};
424
425// Printing of types.
426static inline raw_ostream &operator<<(raw_ostream &OS, Type &T) {
427  T.print(OS);
428  return OS;
429}
430
431// allow isa<PointerType>(x) to work without DerivedTypes.h included.
432template <> struct isa_impl<PointerType, Type> {
433  static inline bool doit(const Type &Ty) {
434    return Ty.getTypeID() == Type::PointerTyID;
435  }
436};
437
438//===----------------------------------------------------------------------===//
439// Provide specializations of GraphTraits to be able to treat a type as a
440// graph of sub types.
441
442template <> struct GraphTraits<Type *> {
443  typedef Type *NodeRef;
444  typedef Type::subtype_iterator ChildIteratorType;
445
446  static NodeRef getEntryNode(Type *T) { return T; }
447  static ChildIteratorType child_begin(NodeRef N) { return N->subtype_begin(); }
448  static ChildIteratorType child_end(NodeRef N) { return N->subtype_end(); }
449};
450
451template <> struct GraphTraits<const Type*> {
452  typedef const Type *NodeRef;
453  typedef Type::subtype_iterator ChildIteratorType;
454
455  static NodeRef getEntryNode(NodeRef T) { return T; }
456  static ChildIteratorType child_begin(NodeRef N) { return N->subtype_begin(); }
457  static ChildIteratorType child_end(NodeRef N) { return N->subtype_end(); }
458};
459
460// Create wrappers for C Binding types (see CBindingWrapping.h).
461DEFINE_ISA_CONVERSION_FUNCTIONS(Type, LLVMTypeRef)
462
463/* Specialized opaque type conversions.
464 */
465inline Type **unwrap(LLVMTypeRef* Tys) {
466  return reinterpret_cast<Type**>(Tys);
467}
468
469inline LLVMTypeRef *wrap(Type **Tys) {
470  return reinterpret_cast<LLVMTypeRef*>(const_cast<Type**>(Tys));
471}
472
473} // End llvm namespace
474
475#endif
476