1//===- AttributeImpl.h - Attribute Internals --------------------*- 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/// \file
10/// This file defines various helper methods and classes used by
11/// LLVMContextImpl for creating and managing attributes.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_LIB_IR_ATTRIBUTEIMPL_H
16#define LLVM_LIB_IR_ATTRIBUTEIMPL_H
17
18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/FoldingSet.h"
20#include "llvm/ADT/StringRef.h"
21#include "llvm/IR/Attributes.h"
22#include "llvm/Support/TrailingObjects.h"
23#include <cassert>
24#include <cstddef>
25#include <cstdint>
26#include <string>
27#include <utility>
28
29namespace llvm {
30
31class LLVMContext;
32class Type;
33
34//===----------------------------------------------------------------------===//
35/// \class
36/// This class represents a single, uniqued attribute. That attribute
37/// could be a single enum, a tuple, or a string.
38class AttributeImpl : public FoldingSetNode {
39  unsigned char KindID; ///< Holds the AttrEntryKind of the attribute
40
41protected:
42  enum AttrEntryKind {
43    EnumAttrEntry,
44    IntAttrEntry,
45    StringAttrEntry,
46    TypeAttrEntry,
47  };
48
49  AttributeImpl(AttrEntryKind KindID) : KindID(KindID) {}
50
51public:
52  // AttributesImpl is uniqued, these should not be available.
53  AttributeImpl(const AttributeImpl &) = delete;
54  AttributeImpl &operator=(const AttributeImpl &) = delete;
55
56  virtual ~AttributeImpl();
57
58  bool isEnumAttribute() const { return KindID == EnumAttrEntry; }
59  bool isIntAttribute() const { return KindID == IntAttrEntry; }
60  bool isStringAttribute() const { return KindID == StringAttrEntry; }
61  bool isTypeAttribute() const { return KindID == TypeAttrEntry; }
62
63  bool hasAttribute(Attribute::AttrKind A) const;
64  bool hasAttribute(StringRef Kind) const;
65
66  Attribute::AttrKind getKindAsEnum() const;
67  uint64_t getValueAsInt() const;
68
69  StringRef getKindAsString() const;
70  StringRef getValueAsString() const;
71
72  Type *getValueAsType() const;
73
74  /// Used when sorting the attributes.
75  bool operator<(const AttributeImpl &AI) const;
76
77  void Profile(FoldingSetNodeID &ID) const {
78    if (isEnumAttribute())
79      Profile(ID, getKindAsEnum(), static_cast<uint64_t>(0));
80    else if (isIntAttribute())
81      Profile(ID, getKindAsEnum(), getValueAsInt());
82    else if (isStringAttribute())
83      Profile(ID, getKindAsString(), getValueAsString());
84    else
85      Profile(ID, getKindAsEnum(), getValueAsType());
86  }
87
88  static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
89                      uint64_t Val) {
90    ID.AddInteger(Kind);
91    if (Val) ID.AddInteger(Val);
92  }
93
94  static void Profile(FoldingSetNodeID &ID, StringRef Kind, StringRef Values) {
95    ID.AddString(Kind);
96    if (!Values.empty()) ID.AddString(Values);
97  }
98
99  static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
100                      Type *Ty) {
101    ID.AddInteger(Kind);
102    ID.AddPointer(Ty);
103  }
104};
105
106//===----------------------------------------------------------------------===//
107/// \class
108/// A set of classes that contain the value of the
109/// attribute object. There are three main categories: enum attribute entries,
110/// represented by Attribute::AttrKind; alignment attribute entries; and string
111/// attribute enties, which are for target-dependent attributes.
112
113class EnumAttributeImpl : public AttributeImpl {
114  virtual void anchor();
115
116  Attribute::AttrKind Kind;
117
118protected:
119  EnumAttributeImpl(AttrEntryKind ID, Attribute::AttrKind Kind)
120      : AttributeImpl(ID), Kind(Kind) {}
121
122public:
123  EnumAttributeImpl(Attribute::AttrKind Kind)
124      : AttributeImpl(EnumAttrEntry), Kind(Kind) {}
125
126  Attribute::AttrKind getEnumKind() const { return Kind; }
127};
128
129class IntAttributeImpl : public EnumAttributeImpl {
130  uint64_t Val;
131
132  void anchor() override;
133
134public:
135  IntAttributeImpl(Attribute::AttrKind Kind, uint64_t Val)
136      : EnumAttributeImpl(IntAttrEntry, Kind), Val(Val) {
137    assert((Kind == Attribute::Alignment || Kind == Attribute::StackAlignment ||
138            Kind == Attribute::Dereferenceable ||
139            Kind == Attribute::DereferenceableOrNull ||
140            Kind == Attribute::AllocSize) &&
141           "Wrong kind for int attribute!");
142  }
143
144  uint64_t getValue() const { return Val; }
145};
146
147class StringAttributeImpl : public AttributeImpl {
148  virtual void anchor();
149
150  std::string Kind;
151  std::string Val;
152
153public:
154  StringAttributeImpl(StringRef Kind, StringRef Val = StringRef())
155      : AttributeImpl(StringAttrEntry), Kind(Kind), Val(Val) {}
156
157  StringRef getStringKind() const { return Kind; }
158  StringRef getStringValue() const { return Val; }
159};
160
161class TypeAttributeImpl : public EnumAttributeImpl {
162  void anchor() override;
163
164  Type *Ty;
165
166public:
167  TypeAttributeImpl(Attribute::AttrKind Kind, Type *Ty)
168      : EnumAttributeImpl(TypeAttrEntry, Kind), Ty(Ty) {}
169
170  Type *getTypeValue() const { return Ty; }
171};
172
173//===----------------------------------------------------------------------===//
174/// \class
175/// This class represents a group of attributes that apply to one
176/// element: function, return type, or parameter.
177class AttributeSetNode final
178    : public FoldingSetNode,
179      private TrailingObjects<AttributeSetNode, Attribute> {
180  friend TrailingObjects;
181
182  unsigned NumAttrs; ///< Number of attributes in this node.
183  /// Bitset with a bit for each available attribute Attribute::AttrKind.
184  uint8_t AvailableAttrs[12] = {};
185
186  AttributeSetNode(ArrayRef<Attribute> Attrs);
187
188public:
189  // AttributesSetNode is uniqued, these should not be available.
190  AttributeSetNode(const AttributeSetNode &) = delete;
191  AttributeSetNode &operator=(const AttributeSetNode &) = delete;
192
193  void operator delete(void *p) { ::operator delete(p); }
194
195  static AttributeSetNode *get(LLVMContext &C, const AttrBuilder &B);
196
197  static AttributeSetNode *get(LLVMContext &C, ArrayRef<Attribute> Attrs);
198
199  /// Return the number of attributes this AttributeList contains.
200  unsigned getNumAttributes() const { return NumAttrs; }
201
202  bool hasAttribute(Attribute::AttrKind Kind) const {
203    return AvailableAttrs[Kind / 8] & ((uint64_t)1) << (Kind % 8);
204  }
205  bool hasAttribute(StringRef Kind) const;
206  bool hasAttributes() const { return NumAttrs != 0; }
207
208  Attribute getAttribute(Attribute::AttrKind Kind) const;
209  Attribute getAttribute(StringRef Kind) const;
210
211  MaybeAlign getAlignment() const;
212  MaybeAlign getStackAlignment() const;
213  uint64_t getDereferenceableBytes() const;
214  uint64_t getDereferenceableOrNullBytes() const;
215  std::pair<unsigned, Optional<unsigned>> getAllocSizeArgs() const;
216  std::string getAsString(bool InAttrGrp) const;
217  Type *getByValType() const;
218
219  using iterator = const Attribute *;
220
221  iterator begin() const { return getTrailingObjects<Attribute>(); }
222  iterator end() const { return begin() + NumAttrs; }
223
224  void Profile(FoldingSetNodeID &ID) const {
225    Profile(ID, makeArrayRef(begin(), end()));
226  }
227
228  static void Profile(FoldingSetNodeID &ID, ArrayRef<Attribute> AttrList) {
229    for (const auto &Attr : AttrList)
230      Attr.Profile(ID);
231  }
232};
233
234using IndexAttrPair = std::pair<unsigned, AttributeSet>;
235
236//===----------------------------------------------------------------------===//
237/// \class
238/// This class represents a set of attributes that apply to the function,
239/// return type, and parameters.
240class AttributeListImpl final
241    : public FoldingSetNode,
242      private TrailingObjects<AttributeListImpl, AttributeSet> {
243  friend class AttributeList;
244  friend TrailingObjects;
245
246private:
247  LLVMContext &Context;
248  unsigned NumAttrSets; ///< Number of entries in this set.
249  /// Bitset with a bit for each available attribute Attribute::AttrKind.
250  uint8_t AvailableFunctionAttrs[12] = {};
251
252  // Helper fn for TrailingObjects class.
253  size_t numTrailingObjects(OverloadToken<AttributeSet>) { return NumAttrSets; }
254
255public:
256  AttributeListImpl(LLVMContext &C, ArrayRef<AttributeSet> Sets);
257
258  // AttributesSetImpt is uniqued, these should not be available.
259  AttributeListImpl(const AttributeListImpl &) = delete;
260  AttributeListImpl &operator=(const AttributeListImpl &) = delete;
261
262  void operator delete(void *p) { ::operator delete(p); }
263
264  /// Get the context that created this AttributeListImpl.
265  LLVMContext &getContext() { return Context; }
266
267  /// Return true if the AttributeSet or the FunctionIndex has an
268  /// enum attribute of the given kind.
269  bool hasFnAttribute(Attribute::AttrKind Kind) const {
270    return AvailableFunctionAttrs[Kind / 8] & ((uint64_t)1) << (Kind % 8);
271  }
272
273  using iterator = const AttributeSet *;
274
275  iterator begin() const { return getTrailingObjects<AttributeSet>(); }
276  iterator end() const { return begin() + NumAttrSets; }
277
278  void Profile(FoldingSetNodeID &ID) const;
279  static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeSet> Nodes);
280
281  void dump() const;
282};
283
284} // end namespace llvm
285
286#endif // LLVM_LIB_IR_ATTRIBUTEIMPL_H
287