lib/IR/AttributeImpl.h

   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
  29 namespace llvm {
  30
  31 class LLVMContext;
  32 class 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.
  38 class AttributeImpl : public FoldingSetNode {
  39   unsigned char KindID; ///< Holds the AttrEntryKind of the attribute
  40
  41 protected:
  42   enum AttrEntryKind {
  43     EnumAttrEntry,
  44     IntAttrEntry,
  45     StringAttrEntry,
  46     TypeAttrEntry,
  47   };
  48
  49   AttributeImpl(AttrEntryKind KindID) : KindID(KindID) {}
  50
  51 public:
  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
 113 class EnumAttributeImpl : public AttributeImpl {
 114   virtual void anchor();
 115
 116   Attribute::AttrKind Kind;
 117
 118 protected:
 119   EnumAttributeImpl(AttrEntryKind ID, Attribute::AttrKind Kind)
 120       : AttributeImpl(ID), Kind(Kind) {}
 121
 122 public:
 123   EnumAttributeImpl(Attribute::AttrKind Kind)
 124       : AttributeImpl(EnumAttrEntry), Kind(Kind) {}
 125
 126   Attribute::AttrKind getEnumKind() const { return Kind; }
 127 };
 128
 129 class IntAttributeImpl : public EnumAttributeImpl {
 130   uint64_t Val;
 131
 132   void anchor() override;
 133
 134 public:
 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
 147 class StringAttributeImpl : public AttributeImpl {
 148   virtual void anchor();
 149
 150   std::string Kind;
 151   std::string Val;
 152
 153 public:
 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
 161 class TypeAttributeImpl : public EnumAttributeImpl {
 162   void anchor() override;
 163
 164   Type *Ty;
 165
 166 public:
 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.
 177 class 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
 188 public:
 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
 234 using 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.
 240 class AttributeListImpl final
 241     : public FoldingSetNode,
 242       private TrailingObjects<AttributeListImpl, AttributeSet> {
 243   friend class AttributeList;
 244   friend TrailingObjects;
 245
 246 private:
 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
 255 public:
 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