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 to sort attributes. KindOnly controls if the sort includes the
  90   /// attributes' values or just the kind.
  91   int cmp(const AttributeImpl &AI, bool KindOnly) const;
  92   /// Used when sorting the attributes.
  93   bool operator<(const AttributeImpl &AI) const;
  94
  95   void Profile(FoldingSetNodeID &ID) const {
  96     if (isEnumAttribute())
  97       Profile(ID, getKindAsEnum());
  98     else if (isIntAttribute())
  99       Profile(ID, getKindAsEnum(), getValueAsInt());
 100     else if (isStringAttribute())
 101       Profile(ID, getKindAsString(), getValueAsString());
 102     else if (isTypeAttribute())
 103       Profile(ID, getKindAsEnum(), getValueAsType());
 104     else if (isConstantRangeAttribute())
 105       Profile(ID, getKindAsEnum(), getValueAsConstantRange());
 106     else
 107       Profile(ID, getKindAsEnum(), getValueAsConstantRangeList());
 108   }
 109
 110   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind) {
 111     assert(Attribute::isEnumAttrKind(Kind) && "Expected enum attribute");
 112     ID.AddInteger(Kind);
 113   }
 114
 115   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 116                       uint64_t Val) {
 117     assert(Attribute::isIntAttrKind(Kind) && "Expected int attribute");
 118     ID.AddInteger(Kind);
 119     ID.AddInteger(Val);
 120   }
 121
 122   static void Profile(FoldingSetNodeID &ID, StringRef Kind, StringRef Values) {
 123     ID.AddString(Kind);
 124     if (!Values.empty()) ID.AddString(Values);
 125   }
 126
 127   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 128                       Type *Ty) {
 129     ID.AddInteger(Kind);
 130     ID.AddPointer(Ty);
 131   }
 132
 133   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 134                       const ConstantRange &CR) {
 135     ID.AddInteger(Kind);
 136     CR.getLower().Profile(ID);
 137     CR.getUpper().Profile(ID);
 138   }
 139
 140   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
 141                       ArrayRef<ConstantRange> Val) {
 142     ID.AddInteger(Kind);
 143     ID.AddInteger(Val.size());
 144     for (auto &CR : Val) {
 145       CR.getLower().Profile(ID);
 146       CR.getUpper().Profile(ID);
 147     }
 148   }
 149 };
 150
 151 static_assert(std::is_trivially_destructible<AttributeImpl>::value,
 152               "AttributeImpl should be trivially destructible");
 153
 154 //===----------------------------------------------------------------------===//
 155 /// \class
 156 /// A set of classes that contain the value of the
 157 /// attribute object. There are three main categories: enum attribute entries,
 158 /// represented by Attribute::AttrKind; alignment attribute entries; and string
 159 /// attribute enties, which are for target-dependent attributes.
 160
 161 class EnumAttributeImpl : public AttributeImpl {
 162   Attribute::AttrKind Kind;
 163
 164 protected:
 165   EnumAttributeImpl(AttrEntryKind ID, Attribute::AttrKind Kind)
 166       : AttributeImpl(ID), Kind(Kind) {}
 167
 168 public:
 169   EnumAttributeImpl(Attribute::AttrKind Kind)
 170       : AttributeImpl(EnumAttrEntry), Kind(Kind) {
 171     assert(Kind != Attribute::AttrKind::None &&
 172            "Can't create a None attribute!");
 173   }
 174
 175   Attribute::AttrKind getEnumKind() const { return Kind; }
 176 };
 177
 178 class IntAttributeImpl : public EnumAttributeImpl {
 179   uint64_t Val;
 180
 181 public:
 182   IntAttributeImpl(Attribute::AttrKind Kind, uint64_t Val)
 183       : EnumAttributeImpl(IntAttrEntry, Kind), Val(Val) {
 184     assert(Attribute::isIntAttrKind(Kind) &&
 185            "Wrong kind for int attribute!");
 186   }
 187
 188   uint64_t getValue() const { return Val; }
 189 };
 190
 191 class StringAttributeImpl final
 192     : public AttributeImpl,
 193       private TrailingObjects<StringAttributeImpl, char> {
 194   friend TrailingObjects;
 195
 196   unsigned KindSize;
 197   unsigned ValSize;
 198   size_t numTrailingObjects(OverloadToken<char>) const {
 199     return KindSize + 1 + ValSize + 1;
 200   }
 201
 202 public:
 203   StringAttributeImpl(StringRef Kind, StringRef Val = StringRef())
 204       : AttributeImpl(StringAttrEntry), KindSize(Kind.size()),
 205         ValSize(Val.size()) {
 206     char *TrailingString = getTrailingObjects<char>();
 207     // Some users rely on zero-termination.
 208     llvm::copy(Kind, TrailingString);
 209     TrailingString[KindSize] = '\0';
 210     llvm::copy(Val, &TrailingString[KindSize + 1]);
 211     TrailingString[KindSize + 1 + ValSize] = '\0';
 212   }
 213
 214   StringRef getStringKind() const {
 215     return StringRef(getTrailingObjects<char>(), KindSize);
 216   }
 217   StringRef getStringValue() const {
 218     return StringRef(getTrailingObjects<char>() + KindSize + 1, ValSize);
 219   }
 220
 221   static size_t totalSizeToAlloc(StringRef Kind, StringRef Val) {
 222     return TrailingObjects::totalSizeToAlloc<char>(Kind.size() + 1 +
 223                                                    Val.size() + 1);
 224   }
 225 };
 226
 227 class TypeAttributeImpl : public EnumAttributeImpl {
 228   Type *Ty;
 229
 230 public:
 231   TypeAttributeImpl(Attribute::AttrKind Kind, Type *Ty)
 232       : EnumAttributeImpl(TypeAttrEntry, Kind), Ty(Ty) {}
 233
 234   Type *getTypeValue() const { return Ty; }
 235 };
 236
 237 class ConstantRangeAttributeImpl : public EnumAttributeImpl {
 238   ConstantRange CR;
 239
 240 public:
 241   ConstantRangeAttributeImpl(Attribute::AttrKind Kind, const ConstantRange &CR)
 242       : EnumAttributeImpl(ConstantRangeAttrEntry, Kind), CR(CR) {}
 243
 244   const ConstantRange &getConstantRangeValue() const { return CR; }
 245 };
 246
 247 class ConstantRangeListAttributeImpl final
 248     : public EnumAttributeImpl,
 249       private TrailingObjects<ConstantRangeListAttributeImpl, ConstantRange> {
 250   friend TrailingObjects;
 251
 252   unsigned Size;
 253   size_t numTrailingObjects(OverloadToken<ConstantRange>) const { return Size; }
 254
 255 public:
 256   ConstantRangeListAttributeImpl(Attribute::AttrKind Kind,
 257                                  ArrayRef<ConstantRange> Val)
 258       : EnumAttributeImpl(ConstantRangeListAttrEntry, Kind), Size(Val.size()) {
 259     assert(Size > 0);
 260     ConstantRange *TrailingCR = getTrailingObjects<ConstantRange>();
 261     std::uninitialized_copy(Val.begin(), Val.end(), TrailingCR);
 262   }
 263
 264   ~ConstantRangeListAttributeImpl() {
 265     ConstantRange *TrailingCR = getTrailingObjects<ConstantRange>();
 266     for (unsigned I = 0; I != Size; ++I)
 267       TrailingCR[I].~ConstantRange();
 268   }
 269
 270   ArrayRef<ConstantRange> getConstantRangeListValue() const {
 271     return ArrayRef(getTrailingObjects<ConstantRange>(), Size);
 272   }
 273
 274   static size_t totalSizeToAlloc(ArrayRef<ConstantRange> Val) {
 275     return TrailingObjects::totalSizeToAlloc<ConstantRange>(Val.size());
 276   }
 277 };
 278
 279 class AttributeBitSet {
 280   /// Bitset with a bit for each available attribute Attribute::AttrKind.
 281   uint8_t AvailableAttrs[16] = {};
 282   static_assert(Attribute::EndAttrKinds <= sizeof(AvailableAttrs) * CHAR_BIT,
 283                 "Too many attributes");
 284
 285 public:
 286   bool hasAttribute(Attribute::AttrKind Kind) const {
 287     return AvailableAttrs[Kind / 8] & (1 << (Kind % 8));
 288   }
 289
 290   void addAttribute(Attribute::AttrKind Kind) {
 291     AvailableAttrs[Kind / 8] |= 1 << (Kind % 8);
 292   }
 293 };
 294
 295 //===----------------------------------------------------------------------===//
 296 /// \class
 297 /// This class represents a group of attributes that apply to one
 298 /// element: function, return type, or parameter.
 299 class AttributeSetNode final
 300     : public FoldingSetNode,
 301       private TrailingObjects<AttributeSetNode, Attribute> {
 302   friend TrailingObjects;
 303
 304   unsigned NumAttrs; ///< Number of attributes in this node.
 305   AttributeBitSet AvailableAttrs; ///< Available enum attributes.
 306
 307   DenseMap<StringRef, Attribute> StringAttrs;
 308
 309   AttributeSetNode(ArrayRef<Attribute> Attrs);
 310
 311   static AttributeSetNode *getSorted(LLVMContext &C,
 312                                      ArrayRef<Attribute> SortedAttrs);
 313   std::optional<Attribute> findEnumAttribute(Attribute::AttrKind Kind) const;
 314
 315 public:
 316   // AttributesSetNode is uniqued, these should not be available.
 317   AttributeSetNode(const AttributeSetNode &) = delete;
 318   AttributeSetNode &operator=(const AttributeSetNode &) = delete;
 319
 320   void operator delete(void *p) { ::operator delete(p); }
 321
 322   static AttributeSetNode *get(LLVMContext &C, const AttrBuilder &B);
 323
 324   static AttributeSetNode *get(LLVMContext &C, ArrayRef<Attribute> Attrs);
 325
 326   /// Return the number of attributes this AttributeList contains.
 327   unsigned getNumAttributes() const { return NumAttrs; }
 328
 329   bool hasAttribute(Attribute::AttrKind Kind) const {
 330     return AvailableAttrs.hasAttribute(Kind);
 331   }
 332   bool hasAttribute(StringRef Kind) const;
 333   bool hasAttributes() const { return NumAttrs != 0; }
 334
 335   Attribute getAttribute(Attribute::AttrKind Kind) const;
 336   Attribute getAttribute(StringRef Kind) const;
 337
 338   MaybeAlign getAlignment() const;
 339   MaybeAlign getStackAlignment() const;
 340   uint64_t getDereferenceableBytes() const;
 341   uint64_t getDereferenceableOrNullBytes() const;
 342   std::optional<std::pair<unsigned, std::optional<unsigned>>> getAllocSizeArgs()
 343       const;
 344   unsigned getVScaleRangeMin() const;
 345   std::optional<unsigned> getVScaleRangeMax() const;
 346   UWTableKind getUWTableKind() const;
 347   AllocFnKind getAllocKind() const;
 348   MemoryEffects getMemoryEffects() const;
 349   CaptureInfo getCaptureInfo() const;
 350   FPClassTest getNoFPClass() const;
 351   std::string getAsString(bool InAttrGrp) const;
 352   Type *getAttributeType(Attribute::AttrKind Kind) const;
 353
 354   using iterator = const Attribute *;
 355
 356   iterator begin() const { return getTrailingObjects<Attribute>(); }
 357   iterator end() const { return begin() + NumAttrs; }
 358
 359   void Profile(FoldingSetNodeID &ID) const {
 360     Profile(ID, ArrayRef(begin(), end()));
 361   }
 362
 363   static void Profile(FoldingSetNodeID &ID, ArrayRef<Attribute> AttrList) {
 364     for (const auto &Attr : AttrList)
 365       Attr.Profile(ID);
 366   }
 367 };
 368
 369 //===----------------------------------------------------------------------===//
 370 /// \class
 371 /// This class represents a set of attributes that apply to the function,
 372 /// return type, and parameters.
 373 class AttributeListImpl final
 374     : public FoldingSetNode,
 375       private TrailingObjects<AttributeListImpl, AttributeSet> {
 376   friend class AttributeList;
 377   friend TrailingObjects;
 378
 379 private:
 380   unsigned NumAttrSets; ///< Number of entries in this set.
 381   /// Available enum function attributes.
 382   AttributeBitSet AvailableFunctionAttrs;
 383   /// Union of enum attributes available at any index.
 384   AttributeBitSet AvailableSomewhereAttrs;
 385
 386   // Helper fn for TrailingObjects class.
 387   size_t numTrailingObjects(OverloadToken<AttributeSet>) { return NumAttrSets; }
 388
 389 public:
 390   AttributeListImpl(ArrayRef<AttributeSet> Sets);
 391
 392   // AttributesSetImpt is uniqued, these should not be available.
 393   AttributeListImpl(const AttributeListImpl &) = delete;
 394   AttributeListImpl &operator=(const AttributeListImpl &) = delete;
 395
 396   /// Return true if the AttributeSet or the FunctionIndex has an
 397   /// enum attribute of the given kind.
 398   bool hasFnAttribute(Attribute::AttrKind Kind) const {
 399     return AvailableFunctionAttrs.hasAttribute(Kind);
 400   }
 401
 402   /// Return true if the specified attribute is set for at least one
 403   /// parameter or for the return value. If Index is not nullptr, the index
 404   /// of a parameter with the specified attribute is provided.
 405   bool hasAttrSomewhere(Attribute::AttrKind Kind,
 406                         unsigned *Index = nullptr) const;
 407
 408   using iterator = const AttributeSet *;
 409
 410   iterator begin() const { return getTrailingObjects<AttributeSet>(); }
 411   iterator end() const { return begin() + NumAttrSets; }
 412
 413   void Profile(FoldingSetNodeID &ID) const;
 414   static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeSet> Nodes);
 415
 416   void dump() const;
 417 };
 418
 419 static_assert(std::is_trivially_destructible<AttributeListImpl>::value,
 420               "AttributeListImpl should be trivially destructible");
 421
 422 } // end namespace llvm
 423
 424 #endif // LLVM_LIB_IR_ATTRIBUTEIMPL_H