llvm/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/DenseMap.h"
  20 #include "llvm/ADT/FoldingSet.h"
  21 #include "llvm/ADT/StringRef.h"
  22 #include "llvm/IR/Attributes.h"
  23 #include "llvm/IR/ConstantRange.h"
  24 #include "llvm/IR/ConstantRangeList.h"
  25 #include "llvm/Support/TrailingObjects.h"
  26 #include <cassert>
  27 #include <cstddef>
  28 #include <cstdint>
  29 #include <optional>
  30 #include <string>
  31 #include <utility>
  32
  33 namespace llvm {
  34
  35 class LLVMContext;
  36 class Type;
  37
  38 //===----------------------------------------------------------------------===//
  39 /// \class
  40 /// This class represents a single, uniqued attribute. That attribute
  41 /// could be a single enum, a tuple, or a string.
  42 class AttributeImpl : public FoldingSetNode {
  43   unsigned char KindID; ///< Holds the AttrEntryKind of the attribute
  44
  45 protected:
  46   enum AttrEntryKind {
  47     EnumAttrEntry,
  48     IntAttrEntry,
  49     StringAttrEntry,
  50     TypeAttrEntry,
  51     ConstantRangeAttrEntry,
  52     ConstantRangeListAttrEntry,
  53   };
  54
  55   AttributeImpl(AttrEntryKind KindID) : KindID(KindID) {}
  56
  57 public:
  58   // AttributesImpl is uniqued, these should not be available.
  59   AttributeImpl(const AttributeImpl &) = delete;
  60   AttributeImpl &operator=(const AttributeImpl &) = delete;
  61
  62   bool isEnumAttribute() const { return KindID == EnumAttrEntry; }
  63   bool isIntAttribute() const { return KindID == IntAttrEntry; }
  64   bool isStringAttribute() const { return KindID == StringAttrEntry; }
  65   bool isTypeAttribute() const { return KindID == TypeAttrEntry; }
  66   bool isConstantRangeAttribute() const {
  67     return KindID == ConstantRangeAttrEntry;
  68   }
  69   bool isConstantRangeListAttribute() const {
  70     return KindID == ConstantRangeListAttrEntry;
  71   }
  72
  73   bool hasAttribute(Attribute::AttrKind A) const;
  74   bool hasAttribute(StringRef Kind) const;
  75
  76   Attribute::AttrKind getKindAsEnum() const;
  77   uint64_t getValueAsInt() const;
  78   bool getValueAsBool() const;
  79
  80   StringRef getKindAsString() const;
  81   StringRef getValueAsString() const;
  82
  83   Type *getValueAsType() const;
  84
  85   const ConstantRange &getValueAsConstantRange() const;
  86
  87   ArrayRef<ConstantRange> getValueAsConstantRangeList() const;
  88
  89   /// Used when sorting the attributes.
  90   bool operator<(const AttributeImpl &AI) const;
  91
  92   void Profile(FoldingSetNodeID &ID) const {
  93     if (isEnumAttribute())
  94       Profile(ID, getKindAsEnum());
  95     else if (isIntAttribute())
  96       Profile(ID, getKindAsEnum(), getValueAsInt());
  97     else if (isStringAttribute())
  98       Profile(ID, getKindAsString(), getValueAsString());
  99     else if (isTypeAttribute())
 100       Profile(ID, getKindAsEnum(), getValueAsType());
 101     else if (isConstantRangeAttribute())
 102       Profile(ID, getKindAsEnum(), getValueAsConstantRange());
 103     else
 104       Profile(ID, getKindAsEnum(), getValueAsConstantRangeList());
 105   }
 106
 107   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind) {
 108     assert(Attribute::isEnumAttrKind(Kind) && "Expected enum attribute");
 109     ID.AddInteger(Kind);
 110   }
 111
 112   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 113                       uint64_t Val) {
 114     assert(Attribute::isIntAttrKind(Kind) && "Expected int attribute");
 115     ID.AddInteger(Kind);
 116     ID.AddInteger(Val);
 117   }
 118
 119   static void Profile(FoldingSetNodeID &ID, StringRef Kind, StringRef Values) {
 120     ID.AddString(Kind);
 121     if (!Values.empty()) ID.AddString(Values);
 122   }
 123
 124   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 125                       Type *Ty) {
 126     ID.AddInteger(Kind);
 127     ID.AddPointer(Ty);
 128   }
 129
 130   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 131                       const ConstantRange &CR) {
 132     ID.AddInteger(Kind);
 133     CR.getLower().Profile(ID);
 134     CR.getUpper().Profile(ID);
 135   }
 136
 137   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 138                       ArrayRef<ConstantRange> Val) {
 139     ID.AddInteger(Kind);
 140     ID.AddInteger(Val.size());
 141     for (auto &CR : Val) {
 142       CR.getLower().Profile(ID);
 143       CR.getUpper().Profile(ID);
 144     }
 145   }
 146 };
 147
 148 static_assert(std::is_trivially_destructible<AttributeImpl>::value,
 149               "AttributeImpl should be trivially destructible");
 150
 151 //===----------------------------------------------------------------------===//
 152 /// \class
 153 /// A set of classes that contain the value of the
 154 /// attribute object. There are three main categories: enum attribute entries,
 155 /// represented by Attribute::AttrKind; alignment attribute entries; and string
 156 /// attribute enties, which are for target-dependent attributes.
 157
 158 class EnumAttributeImpl : public AttributeImpl {
 159   Attribute::AttrKind Kind;
 160
 161 protected:
 162   EnumAttributeImpl(AttrEntryKind ID, Attribute::AttrKind Kind)
 163       : AttributeImpl(ID), Kind(Kind) {}
 164
 165 public:
 166   EnumAttributeImpl(Attribute::AttrKind Kind)
 167       : AttributeImpl(EnumAttrEntry), Kind(Kind) {
 168     assert(Kind != Attribute::AttrKind::None &&
 169            "Can't create a None attribute!");
 170   }
 171
 172   Attribute::AttrKind getEnumKind() const { return Kind; }
 173 };
 174
 175 class IntAttributeImpl : public EnumAttributeImpl {
 176   uint64_t Val;
 177
 178 public:
 179   IntAttributeImpl(Attribute::AttrKind Kind, uint64_t Val)
 180       : EnumAttributeImpl(IntAttrEntry, Kind), Val(Val) {
 181     assert(Attribute::isIntAttrKind(Kind) &&
 182            "Wrong kind for int attribute!");
 183   }
 184
 185   uint64_t getValue() const { return Val; }
 186 };
 187
 188 class StringAttributeImpl final
 189     : public AttributeImpl,
 190       private TrailingObjects<StringAttributeImpl, char> {
 191   friend TrailingObjects;
 192
 193   unsigned KindSize;
 194   unsigned ValSize;
 195   size_t numTrailingObjects(OverloadToken<char>) const {
 196     return KindSize + 1 + ValSize + 1;
 197   }
 198
 199 public:
 200   StringAttributeImpl(StringRef Kind, StringRef Val = StringRef())
 201       : AttributeImpl(StringAttrEntry), KindSize(Kind.size()),
 202         ValSize(Val.size()) {
 203     char *TrailingString = getTrailingObjects<char>();
 204     // Some users rely on zero-termination.
 205     llvm::copy(Kind, TrailingString);
 206     TrailingString[KindSize] = '\0';
 207     llvm::copy(Val, &TrailingString[KindSize + 1]);
 208     TrailingString[KindSize + 1 + ValSize] = '\0';
 209   }
 210
 211   StringRef getStringKind() const {
 212     return StringRef(getTrailingObjects<char>(), KindSize);
 213   }
 214   StringRef getStringValue() const {
 215     return StringRef(getTrailingObjects<char>() + KindSize + 1, ValSize);
 216   }
 217
 218   static size_t totalSizeToAlloc(StringRef Kind, StringRef Val) {
 219     return TrailingObjects::totalSizeToAlloc<char>(Kind.size() + 1 +
 220                                                    Val.size() + 1);
 221   }
 222 };
 223
 224 class TypeAttributeImpl : public EnumAttributeImpl {
 225   Type *Ty;
 226
 227 public:
 228   TypeAttributeImpl(Attribute::AttrKind Kind, Type *Ty)
 229       : EnumAttributeImpl(TypeAttrEntry, Kind), Ty(Ty) {}
 230
 231   Type *getTypeValue() const { return Ty; }
 232 };
 233
 234 class ConstantRangeAttributeImpl : public EnumAttributeImpl {
 235   ConstantRange CR;
 236
 237 public:
 238   ConstantRangeAttributeImpl(Attribute::AttrKind Kind, const ConstantRange &CR)
 239       : EnumAttributeImpl(ConstantRangeAttrEntry, Kind), CR(CR) {}
 240
 241   const ConstantRange &getConstantRangeValue() const { return CR; }
 242 };
 243
 244 class ConstantRangeListAttributeImpl final
 245     : public EnumAttributeImpl,
 246       private TrailingObjects<ConstantRangeListAttributeImpl, ConstantRange> {
 247   friend TrailingObjects;
 248
 249   unsigned Size;
 250   size_t numTrailingObjects(OverloadToken<ConstantRange>) const { return Size; }
 251
 252 public:
 253   ConstantRangeListAttributeImpl(Attribute::AttrKind Kind,
 254                                  ArrayRef<ConstantRange> Val)
 255       : EnumAttributeImpl(ConstantRangeListAttrEntry, Kind), Size(Val.size()) {
 256     assert(Size > 0);
 257     ConstantRange *TrailingCR = getTrailingObjects<ConstantRange>();
 258     std::uninitialized_copy(Val.begin(), Val.end(), TrailingCR);
 259   }
 260
 261   ~ConstantRangeListAttributeImpl() {
 262     ConstantRange *TrailingCR = getTrailingObjects<ConstantRange>();
 263     for (unsigned I = 0; I != Size; ++I)
 264       TrailingCR[I].~ConstantRange();
 265   }
 266
 267   ArrayRef<ConstantRange> getConstantRangeListValue() const {
 268     return ArrayRef(getTrailingObjects<ConstantRange>(), Size);
 269   }
 270
 271   static size_t totalSizeToAlloc(ArrayRef<ConstantRange> Val) {
 272     return TrailingObjects::totalSizeToAlloc<ConstantRange>(Val.size());
 273   }
 274 };
 275
 276 class AttributeBitSet {
 277   /// Bitset with a bit for each available attribute Attribute::AttrKind.
 278   uint8_t AvailableAttrs[12] = {};
 279   static_assert(Attribute::EndAttrKinds <= sizeof(AvailableAttrs) * CHAR_BIT,
 280                 "Too many attributes");
 281
 282 public:
 283   bool hasAttribute(Attribute::AttrKind Kind) const {
 284     return AvailableAttrs[Kind / 8] & (1 << (Kind % 8));
 285   }
 286
 287   void addAttribute(Attribute::AttrKind Kind) {
 288     AvailableAttrs[Kind / 8] |= 1 << (Kind % 8);
 289   }
 290 };
 291
 292 //===----------------------------------------------------------------------===//
 293 /// \class
 294 /// This class represents a group of attributes that apply to one
 295 /// element: function, return type, or parameter.
 296 class AttributeSetNode final
 297     : public FoldingSetNode,
 298       private TrailingObjects<AttributeSetNode, Attribute> {
 299   friend TrailingObjects;
 300
 301   unsigned NumAttrs; ///< Number of attributes in this node.
 302   AttributeBitSet AvailableAttrs; ///< Available enum attributes.
 303
 304   DenseMap<StringRef, Attribute> StringAttrs;
 305
 306   AttributeSetNode(ArrayRef<Attribute> Attrs);
 307
 308   static AttributeSetNode *getSorted(LLVMContext &C,
 309                                      ArrayRef<Attribute> SortedAttrs);
 310   std::optional<Attribute> findEnumAttribute(Attribute::AttrKind Kind) const;
 311
 312 public:
 313   // AttributesSetNode is uniqued, these should not be available.
 314   AttributeSetNode(const AttributeSetNode &) = delete;
 315   AttributeSetNode &operator=(const AttributeSetNode &) = delete;
 316
 317   void operator delete(void *p) { ::operator delete(p); }
 318
 319   static AttributeSetNode *get(LLVMContext &C, const AttrBuilder &B);
 320
 321   static AttributeSetNode *get(LLVMContext &C, ArrayRef<Attribute> Attrs);
 322
 323   /// Return the number of attributes this AttributeList contains.
 324   unsigned getNumAttributes() const { return NumAttrs; }
 325
 326   bool hasAttribute(Attribute::AttrKind Kind) const {
 327     return AvailableAttrs.hasAttribute(Kind);
 328   }
 329   bool hasAttribute(StringRef Kind) const;
 330   bool hasAttributes() const { return NumAttrs != 0; }
 331
 332   Attribute getAttribute(Attribute::AttrKind Kind) const;
 333   Attribute getAttribute(StringRef Kind) const;
 334
 335   MaybeAlign getAlignment() const;
 336   MaybeAlign getStackAlignment() const;
 337   uint64_t getDereferenceableBytes() const;
 338   uint64_t getDereferenceableOrNullBytes() const;
 339   std::optional<std::pair<unsigned, std::optional<unsigned>>> getAllocSizeArgs()
 340       const;
 341   unsigned getVScaleRangeMin() const;
 342   std::optional<unsigned> getVScaleRangeMax() const;
 343   UWTableKind getUWTableKind() const;
 344   AllocFnKind getAllocKind() const;
 345   MemoryEffects getMemoryEffects() const;
 346   FPClassTest getNoFPClass() const;
 347   std::string getAsString(bool InAttrGrp) const;
 348   Type *getAttributeType(Attribute::AttrKind Kind) const;
 349
 350   using iterator = const Attribute *;
 351
 352   iterator begin() const { return getTrailingObjects<Attribute>(); }
 353   iterator end() const { return begin() + NumAttrs; }
 354
 355   void Profile(FoldingSetNodeID &ID) const {
 356     Profile(ID, ArrayRef(begin(), end()));
 357   }
 358
 359   static void Profile(FoldingSetNodeID &ID, ArrayRef<Attribute> AttrList) {
 360     for (const auto &Attr : AttrList)
 361       Attr.Profile(ID);
 362   }
 363 };
 364
 365 //===----------------------------------------------------------------------===//
 366 /// \class
 367 /// This class represents a set of attributes that apply to the function,
 368 /// return type, and parameters.
 369 class AttributeListImpl final
 370     : public FoldingSetNode,
 371       private TrailingObjects<AttributeListImpl, AttributeSet> {
 372   friend class AttributeList;
 373   friend TrailingObjects;
 374
 375 private:
 376   unsigned NumAttrSets; ///< Number of entries in this set.
 377   /// Available enum function attributes.
 378   AttributeBitSet AvailableFunctionAttrs;
 379   /// Union of enum attributes available at any index.
 380   AttributeBitSet AvailableSomewhereAttrs;
 381
 382   // Helper fn for TrailingObjects class.
 383   size_t numTrailingObjects(OverloadToken<AttributeSet>) { return NumAttrSets; }
 384
 385 public:
 386   AttributeListImpl(ArrayRef<AttributeSet> Sets);
 387
 388   // AttributesSetImpt is uniqued, these should not be available.
 389   AttributeListImpl(const AttributeListImpl &) = delete;
 390   AttributeListImpl &operator=(const AttributeListImpl &) = delete;
 391
 392   /// Return true if the AttributeSet or the FunctionIndex has an
 393   /// enum attribute of the given kind.
 394   bool hasFnAttribute(Attribute::AttrKind Kind) const {
 395     return AvailableFunctionAttrs.hasAttribute(Kind);
 396   }
 397
 398   /// Return true if the specified attribute is set for at least one
 399   /// parameter or for the return value. If Index is not nullptr, the index
 400   /// of a parameter with the specified attribute is provided.
 401   bool hasAttrSomewhere(Attribute::AttrKind Kind,
 402                         unsigned *Index = nullptr) const;
 403
 404   using iterator = const AttributeSet *;
 405
 406   iterator begin() const { return getTrailingObjects<AttributeSet>(); }
 407   iterator end() const { return begin() + NumAttrSets; }
 408
 409   void Profile(FoldingSetNodeID &ID) const;
 410   static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeSet> Nodes);
 411
 412   void dump() const;
 413 };
 414
 415 static_assert(std::is_trivially_destructible<AttributeListImpl>::value,
 416               "AttributeListImpl should be trivially destructible");
 417
 418 } // end namespace llvm
 419
 420 #endif // LLVM_LIB_IR_ATTRIBUTEIMPL_H