1 //===- LLVMContextImpl.h - The LLVMContextImpl opaque class -----*- 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 //  This file declares LLVMContextImpl, the opaque implementation
10 //  of LLVMContext.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_IR_LLVMCONTEXTIMPL_H
15 #define LLVM_LIB_IR_LLVMCONTEXTIMPL_H
16 
17 #include "AttributeImpl.h"
18 #include "ConstantsContext.h"
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/ADT/APInt.h"
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/ADT/DenseMapInfo.h"
24 #include "llvm/ADT/DenseSet.h"
25 #include "llvm/ADT/FoldingSet.h"
26 #include "llvm/ADT/Hashing.h"
27 #include "llvm/ADT/Optional.h"
28 #include "llvm/ADT/STLExtras.h"
29 #include "llvm/ADT/SmallPtrSet.h"
30 #include "llvm/ADT/SmallVector.h"
31 #include "llvm/ADT/StringMap.h"
32 #include "llvm/BinaryFormat/Dwarf.h"
33 #include "llvm/IR/Constants.h"
34 #include "llvm/IR/DebugInfoMetadata.h"
35 #include "llvm/IR/DerivedTypes.h"
36 #include "llvm/IR/LLVMContext.h"
37 #include "llvm/IR/LLVMRemarkStreamer.h"
38 #include "llvm/IR/Metadata.h"
39 #include "llvm/IR/TrackingMDRef.h"
40 #include "llvm/Support/Allocator.h"
41 #include "llvm/Support/Casting.h"
42 #include "llvm/Support/StringSaver.h"
43 #include "llvm/Support/YAMLTraits.h"
44 #include <algorithm>
45 #include <cassert>
46 #include <cstddef>
47 #include <cstdint>
48 #include <memory>
49 #include <string>
50 #include <utility>
51 #include <vector>
52 
53 namespace llvm {
54 
55 class StringRef;
56 class Type;
57 class Value;
58 class ValueHandleBase;
59 
60 using DenseMapAPIntKeyInfo = DenseMapInfo<APInt>;
61 
62 struct DenseMapAPFloatKeyInfo {
getEmptyKeyDenseMapAPFloatKeyInfo63   static inline APFloat getEmptyKey() { return APFloat(APFloat::Bogus(), 1); }
getTombstoneKeyDenseMapAPFloatKeyInfo64   static inline APFloat getTombstoneKey() { return APFloat(APFloat::Bogus(), 2); }
65 
getHashValueDenseMapAPFloatKeyInfo66   static unsigned getHashValue(const APFloat &Key) {
67     return static_cast<unsigned>(hash_value(Key));
68   }
69 
isEqualDenseMapAPFloatKeyInfo70   static bool isEqual(const APFloat &LHS, const APFloat &RHS) {
71     return LHS.bitwiseIsEqual(RHS);
72   }
73 };
74 
75 struct AnonStructTypeKeyInfo {
76   struct KeyTy {
77     ArrayRef<Type*> ETypes;
78     bool isPacked;
79 
KeyTyAnonStructTypeKeyInfo::KeyTy80     KeyTy(const ArrayRef<Type*>& E, bool P) :
81       ETypes(E), isPacked(P) {}
82 
KeyTyAnonStructTypeKeyInfo::KeyTy83     KeyTy(const StructType *ST)
84         : ETypes(ST->elements()), isPacked(ST->isPacked()) {}
85 
86     bool operator==(const KeyTy& that) const {
87       if (isPacked != that.isPacked)
88         return false;
89       if (ETypes != that.ETypes)
90         return false;
91       return true;
92     }
93     bool operator!=(const KeyTy& that) const {
94       return !this->operator==(that);
95     }
96   };
97 
getEmptyKeyAnonStructTypeKeyInfo98   static inline StructType* getEmptyKey() {
99     return DenseMapInfo<StructType*>::getEmptyKey();
100   }
101 
getTombstoneKeyAnonStructTypeKeyInfo102   static inline StructType* getTombstoneKey() {
103     return DenseMapInfo<StructType*>::getTombstoneKey();
104   }
105 
getHashValueAnonStructTypeKeyInfo106   static unsigned getHashValue(const KeyTy& Key) {
107     return hash_combine(hash_combine_range(Key.ETypes.begin(),
108                                            Key.ETypes.end()),
109                         Key.isPacked);
110   }
111 
getHashValueAnonStructTypeKeyInfo112   static unsigned getHashValue(const StructType *ST) {
113     return getHashValue(KeyTy(ST));
114   }
115 
isEqualAnonStructTypeKeyInfo116   static bool isEqual(const KeyTy& LHS, const StructType *RHS) {
117     if (RHS == getEmptyKey() || RHS == getTombstoneKey())
118       return false;
119     return LHS == KeyTy(RHS);
120   }
121 
isEqualAnonStructTypeKeyInfo122   static bool isEqual(const StructType *LHS, const StructType *RHS) {
123     return LHS == RHS;
124   }
125 };
126 
127 struct FunctionTypeKeyInfo {
128   struct KeyTy {
129     const Type *ReturnType;
130     ArrayRef<Type*> Params;
131     bool isVarArg;
132 
KeyTyFunctionTypeKeyInfo::KeyTy133     KeyTy(const Type* R, const ArrayRef<Type*>& P, bool V) :
134       ReturnType(R), Params(P), isVarArg(V) {}
KeyTyFunctionTypeKeyInfo::KeyTy135     KeyTy(const FunctionType *FT)
136         : ReturnType(FT->getReturnType()), Params(FT->params()),
137           isVarArg(FT->isVarArg()) {}
138 
139     bool operator==(const KeyTy& that) const {
140       if (ReturnType != that.ReturnType)
141         return false;
142       if (isVarArg != that.isVarArg)
143         return false;
144       if (Params != that.Params)
145         return false;
146       return true;
147     }
148     bool operator!=(const KeyTy& that) const {
149       return !this->operator==(that);
150     }
151   };
152 
getEmptyKeyFunctionTypeKeyInfo153   static inline FunctionType* getEmptyKey() {
154     return DenseMapInfo<FunctionType*>::getEmptyKey();
155   }
156 
getTombstoneKeyFunctionTypeKeyInfo157   static inline FunctionType* getTombstoneKey() {
158     return DenseMapInfo<FunctionType*>::getTombstoneKey();
159   }
160 
getHashValueFunctionTypeKeyInfo161   static unsigned getHashValue(const KeyTy& Key) {
162     return hash_combine(Key.ReturnType,
163                         hash_combine_range(Key.Params.begin(),
164                                            Key.Params.end()),
165                         Key.isVarArg);
166   }
167 
getHashValueFunctionTypeKeyInfo168   static unsigned getHashValue(const FunctionType *FT) {
169     return getHashValue(KeyTy(FT));
170   }
171 
isEqualFunctionTypeKeyInfo172   static bool isEqual(const KeyTy& LHS, const FunctionType *RHS) {
173     if (RHS == getEmptyKey() || RHS == getTombstoneKey())
174       return false;
175     return LHS == KeyTy(RHS);
176   }
177 
isEqualFunctionTypeKeyInfo178   static bool isEqual(const FunctionType *LHS, const FunctionType *RHS) {
179     return LHS == RHS;
180   }
181 };
182 
183 /// Structure for hashing arbitrary MDNode operands.
184 class MDNodeOpsKey {
185   ArrayRef<Metadata *> RawOps;
186   ArrayRef<MDOperand> Ops;
187   unsigned Hash;
188 
189 protected:
MDNodeOpsKey(ArrayRef<Metadata * > Ops)190   MDNodeOpsKey(ArrayRef<Metadata *> Ops)
191       : RawOps(Ops), Hash(calculateHash(Ops)) {}
192 
193   template <class NodeTy>
194   MDNodeOpsKey(const NodeTy *N, unsigned Offset = 0)
195       : Ops(N->op_begin() + Offset, N->op_end()), Hash(N->getHash()) {}
196 
197   template <class NodeTy>
198   bool compareOps(const NodeTy *RHS, unsigned Offset = 0) const {
199     if (getHash() != RHS->getHash())
200       return false;
201 
202     assert((RawOps.empty() || Ops.empty()) && "Two sets of operands?");
203     return RawOps.empty() ? compareOps(Ops, RHS, Offset)
204                           : compareOps(RawOps, RHS, Offset);
205   }
206 
207   static unsigned calculateHash(MDNode *N, unsigned Offset = 0);
208 
209 private:
210   template <class T>
compareOps(ArrayRef<T> Ops,const MDNode * RHS,unsigned Offset)211   static bool compareOps(ArrayRef<T> Ops, const MDNode *RHS, unsigned Offset) {
212     if (Ops.size() != RHS->getNumOperands() - Offset)
213       return false;
214     return std::equal(Ops.begin(), Ops.end(), RHS->op_begin() + Offset);
215   }
216 
217   static unsigned calculateHash(ArrayRef<Metadata *> Ops);
218 
219 public:
getHash()220   unsigned getHash() const { return Hash; }
221 };
222 
223 template <class NodeTy> struct MDNodeKeyImpl;
224 
225 /// Configuration point for MDNodeInfo::isEqual().
226 template <class NodeTy> struct MDNodeSubsetEqualImpl {
227   using KeyTy = MDNodeKeyImpl<NodeTy>;
228 
isSubsetEqualMDNodeSubsetEqualImpl229   static bool isSubsetEqual(const KeyTy &LHS, const NodeTy *RHS) {
230     return false;
231   }
232 
isSubsetEqualMDNodeSubsetEqualImpl233   static bool isSubsetEqual(const NodeTy *LHS, const NodeTy *RHS) {
234     return false;
235   }
236 };
237 
238 /// DenseMapInfo for MDTuple.
239 ///
240 /// Note that we don't need the is-function-local bit, since that's implicit in
241 /// the operands.
242 template <> struct MDNodeKeyImpl<MDTuple> : MDNodeOpsKey {
243   MDNodeKeyImpl(ArrayRef<Metadata *> Ops) : MDNodeOpsKey(Ops) {}
244   MDNodeKeyImpl(const MDTuple *N) : MDNodeOpsKey(N) {}
245 
246   bool isKeyOf(const MDTuple *RHS) const { return compareOps(RHS); }
247 
248   unsigned getHashValue() const { return getHash(); }
249 
250   static unsigned calculateHash(MDTuple *N) {
251     return MDNodeOpsKey::calculateHash(N);
252   }
253 };
254 
255 /// DenseMapInfo for DILocation.
256 template <> struct MDNodeKeyImpl<DILocation> {
257   unsigned Line;
258   unsigned Column;
259   Metadata *Scope;
260   Metadata *InlinedAt;
261   bool ImplicitCode;
262 
263   MDNodeKeyImpl(unsigned Line, unsigned Column, Metadata *Scope,
264                 Metadata *InlinedAt, bool ImplicitCode)
265       : Line(Line), Column(Column), Scope(Scope), InlinedAt(InlinedAt),
266         ImplicitCode(ImplicitCode) {}
267   MDNodeKeyImpl(const DILocation *L)
268       : Line(L->getLine()), Column(L->getColumn()), Scope(L->getRawScope()),
269         InlinedAt(L->getRawInlinedAt()), ImplicitCode(L->isImplicitCode()) {}
270 
271   bool isKeyOf(const DILocation *RHS) const {
272     return Line == RHS->getLine() && Column == RHS->getColumn() &&
273            Scope == RHS->getRawScope() && InlinedAt == RHS->getRawInlinedAt() &&
274            ImplicitCode == RHS->isImplicitCode();
275   }
276 
277   unsigned getHashValue() const {
278     return hash_combine(Line, Column, Scope, InlinedAt, ImplicitCode);
279   }
280 };
281 
282 /// DenseMapInfo for GenericDINode.
283 template <> struct MDNodeKeyImpl<GenericDINode> : MDNodeOpsKey {
284   unsigned Tag;
285   MDString *Header;
286 
287   MDNodeKeyImpl(unsigned Tag, MDString *Header, ArrayRef<Metadata *> DwarfOps)
288       : MDNodeOpsKey(DwarfOps), Tag(Tag), Header(Header) {}
289   MDNodeKeyImpl(const GenericDINode *N)
290       : MDNodeOpsKey(N, 1), Tag(N->getTag()), Header(N->getRawHeader()) {}
291 
292   bool isKeyOf(const GenericDINode *RHS) const {
293     return Tag == RHS->getTag() && Header == RHS->getRawHeader() &&
294            compareOps(RHS, 1);
295   }
296 
297   unsigned getHashValue() const { return hash_combine(getHash(), Tag, Header); }
298 
299   static unsigned calculateHash(GenericDINode *N) {
300     return MDNodeOpsKey::calculateHash(N, 1);
301   }
302 };
303 
304 template <> struct MDNodeKeyImpl<DISubrange> {
305   Metadata *CountNode;
306   Metadata *LowerBound;
307   Metadata *UpperBound;
308   Metadata *Stride;
309 
310   MDNodeKeyImpl(Metadata *CountNode, Metadata *LowerBound, Metadata *UpperBound,
311                 Metadata *Stride)
312       : CountNode(CountNode), LowerBound(LowerBound), UpperBound(UpperBound),
313         Stride(Stride) {}
314   MDNodeKeyImpl(const DISubrange *N)
315       : CountNode(N->getRawCountNode()), LowerBound(N->getRawLowerBound()),
316         UpperBound(N->getRawUpperBound()), Stride(N->getRawStride()) {}
317 
318   bool isKeyOf(const DISubrange *RHS) const {
319     auto BoundsEqual = [=](Metadata *Node1, Metadata *Node2) -> bool {
320       if (Node1 == Node2)
321         return true;
322 
323       ConstantAsMetadata *MD1 = dyn_cast_or_null<ConstantAsMetadata>(Node1);
324       ConstantAsMetadata *MD2 = dyn_cast_or_null<ConstantAsMetadata>(Node2);
325       if (MD1 && MD2) {
326         ConstantInt *CV1 = cast<ConstantInt>(MD1->getValue());
327         ConstantInt *CV2 = cast<ConstantInt>(MD2->getValue());
328         if (CV1->getSExtValue() == CV2->getSExtValue())
329           return true;
330       }
331       return false;
332     };
333 
334     return BoundsEqual(CountNode, RHS->getRawCountNode()) &&
335            BoundsEqual(LowerBound, RHS->getRawLowerBound()) &&
336            BoundsEqual(UpperBound, RHS->getRawUpperBound()) &&
337            BoundsEqual(Stride, RHS->getRawStride());
338   }
339 
340   unsigned getHashValue() const {
341     if (CountNode)
342       if (auto *MD = dyn_cast<ConstantAsMetadata>(CountNode))
343         return hash_combine(cast<ConstantInt>(MD->getValue())->getSExtValue(),
344                             LowerBound, UpperBound, Stride);
345     return hash_combine(CountNode, LowerBound, UpperBound, Stride);
346   }
347 };
348 
349 template <> struct MDNodeKeyImpl<DIGenericSubrange> {
350   Metadata *CountNode;
351   Metadata *LowerBound;
352   Metadata *UpperBound;
353   Metadata *Stride;
354 
355   MDNodeKeyImpl(Metadata *CountNode, Metadata *LowerBound, Metadata *UpperBound,
356                 Metadata *Stride)
357       : CountNode(CountNode), LowerBound(LowerBound), UpperBound(UpperBound),
358         Stride(Stride) {}
359   MDNodeKeyImpl(const DIGenericSubrange *N)
360       : CountNode(N->getRawCountNode()), LowerBound(N->getRawLowerBound()),
361         UpperBound(N->getRawUpperBound()), Stride(N->getRawStride()) {}
362 
363   bool isKeyOf(const DIGenericSubrange *RHS) const {
364     return (CountNode == RHS->getRawCountNode()) &&
365            (LowerBound == RHS->getRawLowerBound()) &&
366            (UpperBound == RHS->getRawUpperBound()) &&
367            (Stride == RHS->getRawStride());
368   }
369 
370   unsigned getHashValue() const {
371     auto *MD = dyn_cast_or_null<ConstantAsMetadata>(CountNode);
372     if (CountNode && MD)
373       return hash_combine(cast<ConstantInt>(MD->getValue())->getSExtValue(),
374                           LowerBound, UpperBound, Stride);
375     return hash_combine(CountNode, LowerBound, UpperBound, Stride);
376   }
377 };
378 
379 template <> struct MDNodeKeyImpl<DIEnumerator> {
380   APInt Value;
381   MDString *Name;
382   bool IsUnsigned;
383 
384   MDNodeKeyImpl(APInt Value, bool IsUnsigned, MDString *Name)
385       : Value(Value), Name(Name), IsUnsigned(IsUnsigned) {}
386   MDNodeKeyImpl(int64_t Value, bool IsUnsigned, MDString *Name)
387       : Value(APInt(64, Value, !IsUnsigned)), Name(Name),
388         IsUnsigned(IsUnsigned) {}
389   MDNodeKeyImpl(const DIEnumerator *N)
390       : Value(N->getValue()), Name(N->getRawName()),
391         IsUnsigned(N->isUnsigned()) {}
392 
393   bool isKeyOf(const DIEnumerator *RHS) const {
394     return Value.getBitWidth() == RHS->getValue().getBitWidth() &&
395            Value == RHS->getValue() && IsUnsigned == RHS->isUnsigned() &&
396            Name == RHS->getRawName();
397   }
398 
399   unsigned getHashValue() const { return hash_combine(Value, Name); }
400 };
401 
402 template <> struct MDNodeKeyImpl<DIBasicType> {
403   unsigned Tag;
404   MDString *Name;
405   uint64_t SizeInBits;
406   uint32_t AlignInBits;
407   unsigned Encoding;
408   unsigned Flags;
409 
410   MDNodeKeyImpl(unsigned Tag, MDString *Name, uint64_t SizeInBits,
411                 uint32_t AlignInBits, unsigned Encoding, unsigned Flags)
412       : Tag(Tag), Name(Name), SizeInBits(SizeInBits), AlignInBits(AlignInBits),
413         Encoding(Encoding), Flags(Flags) {}
414   MDNodeKeyImpl(const DIBasicType *N)
415       : Tag(N->getTag()), Name(N->getRawName()), SizeInBits(N->getSizeInBits()),
416         AlignInBits(N->getAlignInBits()), Encoding(N->getEncoding()), Flags(N->getFlags()) {}
417 
418   bool isKeyOf(const DIBasicType *RHS) const {
419     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
420            SizeInBits == RHS->getSizeInBits() &&
421            AlignInBits == RHS->getAlignInBits() &&
422            Encoding == RHS->getEncoding() &&
423            Flags == RHS->getFlags();
424   }
425 
426   unsigned getHashValue() const {
427     return hash_combine(Tag, Name, SizeInBits, AlignInBits, Encoding);
428   }
429 };
430 
431 template <> struct MDNodeKeyImpl<DIStringType> {
432   unsigned Tag;
433   MDString *Name;
434   Metadata *StringLength;
435   Metadata *StringLengthExp;
436   uint64_t SizeInBits;
437   uint32_t AlignInBits;
438   unsigned Encoding;
439 
440   MDNodeKeyImpl(unsigned Tag, MDString *Name, Metadata *StringLength,
441                 Metadata *StringLengthExp, uint64_t SizeInBits,
442                 uint32_t AlignInBits, unsigned Encoding)
443       : Tag(Tag), Name(Name), StringLength(StringLength),
444         StringLengthExp(StringLengthExp), SizeInBits(SizeInBits),
445         AlignInBits(AlignInBits), Encoding(Encoding) {}
446   MDNodeKeyImpl(const DIStringType *N)
447       : Tag(N->getTag()), Name(N->getRawName()),
448         StringLength(N->getRawStringLength()),
449         StringLengthExp(N->getRawStringLengthExp()),
450         SizeInBits(N->getSizeInBits()), AlignInBits(N->getAlignInBits()),
451         Encoding(N->getEncoding()) {}
452 
453   bool isKeyOf(const DIStringType *RHS) const {
454     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
455            SizeInBits == RHS->getSizeInBits() &&
456            AlignInBits == RHS->getAlignInBits() &&
457            Encoding == RHS->getEncoding();
458   }
459   unsigned getHashValue() const { return hash_combine(Tag, Name, Encoding); }
460 };
461 
462 template <> struct MDNodeKeyImpl<DIDerivedType> {
463   unsigned Tag;
464   MDString *Name;
465   Metadata *File;
466   unsigned Line;
467   Metadata *Scope;
468   Metadata *BaseType;
469   uint64_t SizeInBits;
470   uint64_t OffsetInBits;
471   uint32_t AlignInBits;
472   Optional<unsigned> DWARFAddressSpace;
473   unsigned Flags;
474   Metadata *ExtraData;
475 
476   MDNodeKeyImpl(unsigned Tag, MDString *Name, Metadata *File, unsigned Line,
477                 Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
478                 uint32_t AlignInBits, uint64_t OffsetInBits,
479                 Optional<unsigned> DWARFAddressSpace, unsigned Flags,
480                 Metadata *ExtraData)
481       : Tag(Tag), Name(Name), File(File), Line(Line), Scope(Scope),
482         BaseType(BaseType), SizeInBits(SizeInBits), OffsetInBits(OffsetInBits),
483         AlignInBits(AlignInBits), DWARFAddressSpace(DWARFAddressSpace),
484         Flags(Flags), ExtraData(ExtraData) {}
485   MDNodeKeyImpl(const DIDerivedType *N)
486       : Tag(N->getTag()), Name(N->getRawName()), File(N->getRawFile()),
487         Line(N->getLine()), Scope(N->getRawScope()),
488         BaseType(N->getRawBaseType()), SizeInBits(N->getSizeInBits()),
489         OffsetInBits(N->getOffsetInBits()), AlignInBits(N->getAlignInBits()),
490         DWARFAddressSpace(N->getDWARFAddressSpace()), Flags(N->getFlags()),
491         ExtraData(N->getRawExtraData()) {}
492 
493   bool isKeyOf(const DIDerivedType *RHS) const {
494     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
495            File == RHS->getRawFile() && Line == RHS->getLine() &&
496            Scope == RHS->getRawScope() && BaseType == RHS->getRawBaseType() &&
497            SizeInBits == RHS->getSizeInBits() &&
498            AlignInBits == RHS->getAlignInBits() &&
499            OffsetInBits == RHS->getOffsetInBits() &&
500            DWARFAddressSpace == RHS->getDWARFAddressSpace() &&
501            Flags == RHS->getFlags() &&
502            ExtraData == RHS->getRawExtraData();
503   }
504 
505   unsigned getHashValue() const {
506     // If this is a member inside an ODR type, only hash the type and the name.
507     // Otherwise the hash will be stronger than
508     // MDNodeSubsetEqualImpl::isODRMember().
509     if (Tag == dwarf::DW_TAG_member && Name)
510       if (auto *CT = dyn_cast_or_null<DICompositeType>(Scope))
511         if (CT->getRawIdentifier())
512           return hash_combine(Name, Scope);
513 
514     // Intentionally computes the hash on a subset of the operands for
515     // performance reason. The subset has to be significant enough to avoid
516     // collision "most of the time". There is no correctness issue in case of
517     // collision because of the full check above.
518     return hash_combine(Tag, Name, File, Line, Scope, BaseType, Flags);
519   }
520 };
521 
522 template <> struct MDNodeSubsetEqualImpl<DIDerivedType> {
523   using KeyTy = MDNodeKeyImpl<DIDerivedType>;
524 
525   static bool isSubsetEqual(const KeyTy &LHS, const DIDerivedType *RHS) {
526     return isODRMember(LHS.Tag, LHS.Scope, LHS.Name, RHS);
527   }
528 
529   static bool isSubsetEqual(const DIDerivedType *LHS, const DIDerivedType *RHS) {
530     return isODRMember(LHS->getTag(), LHS->getRawScope(), LHS->getRawName(),
531                        RHS);
532   }
533 
534   /// Subprograms compare equal if they declare the same function in an ODR
535   /// type.
536   static bool isODRMember(unsigned Tag, const Metadata *Scope,
537                           const MDString *Name, const DIDerivedType *RHS) {
538     // Check whether the LHS is eligible.
539     if (Tag != dwarf::DW_TAG_member || !Name)
540       return false;
541 
542     auto *CT = dyn_cast_or_null<DICompositeType>(Scope);
543     if (!CT || !CT->getRawIdentifier())
544       return false;
545 
546     // Compare to the RHS.
547     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
548            Scope == RHS->getRawScope();
549   }
550 };
551 
552 template <> struct MDNodeKeyImpl<DICompositeType> {
553   unsigned Tag;
554   MDString *Name;
555   Metadata *File;
556   unsigned Line;
557   Metadata *Scope;
558   Metadata *BaseType;
559   uint64_t SizeInBits;
560   uint64_t OffsetInBits;
561   uint32_t AlignInBits;
562   unsigned Flags;
563   Metadata *Elements;
564   unsigned RuntimeLang;
565   Metadata *VTableHolder;
566   Metadata *TemplateParams;
567   MDString *Identifier;
568   Metadata *Discriminator;
569   Metadata *DataLocation;
570   Metadata *Associated;
571   Metadata *Allocated;
572   Metadata *Rank;
573 
574   MDNodeKeyImpl(unsigned Tag, MDString *Name, Metadata *File, unsigned Line,
575                 Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
576                 uint32_t AlignInBits, uint64_t OffsetInBits, unsigned Flags,
577                 Metadata *Elements, unsigned RuntimeLang,
578                 Metadata *VTableHolder, Metadata *TemplateParams,
579                 MDString *Identifier, Metadata *Discriminator,
580                 Metadata *DataLocation, Metadata *Associated,
581                 Metadata *Allocated, Metadata *Rank)
582       : Tag(Tag), Name(Name), File(File), Line(Line), Scope(Scope),
583         BaseType(BaseType), SizeInBits(SizeInBits), OffsetInBits(OffsetInBits),
584         AlignInBits(AlignInBits), Flags(Flags), Elements(Elements),
585         RuntimeLang(RuntimeLang), VTableHolder(VTableHolder),
586         TemplateParams(TemplateParams), Identifier(Identifier),
587         Discriminator(Discriminator), DataLocation(DataLocation),
588         Associated(Associated), Allocated(Allocated), Rank(Rank) {}
589   MDNodeKeyImpl(const DICompositeType *N)
590       : Tag(N->getTag()), Name(N->getRawName()), File(N->getRawFile()),
591         Line(N->getLine()), Scope(N->getRawScope()),
592         BaseType(N->getRawBaseType()), SizeInBits(N->getSizeInBits()),
593         OffsetInBits(N->getOffsetInBits()), AlignInBits(N->getAlignInBits()),
594         Flags(N->getFlags()), Elements(N->getRawElements()),
595         RuntimeLang(N->getRuntimeLang()), VTableHolder(N->getRawVTableHolder()),
596         TemplateParams(N->getRawTemplateParams()),
597         Identifier(N->getRawIdentifier()),
598         Discriminator(N->getRawDiscriminator()),
599         DataLocation(N->getRawDataLocation()),
600         Associated(N->getRawAssociated()), Allocated(N->getRawAllocated()),
601         Rank(N->getRawRank()) {}
602 
603   bool isKeyOf(const DICompositeType *RHS) const {
604     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
605            File == RHS->getRawFile() && Line == RHS->getLine() &&
606            Scope == RHS->getRawScope() && BaseType == RHS->getRawBaseType() &&
607            SizeInBits == RHS->getSizeInBits() &&
608            AlignInBits == RHS->getAlignInBits() &&
609            OffsetInBits == RHS->getOffsetInBits() && Flags == RHS->getFlags() &&
610            Elements == RHS->getRawElements() &&
611            RuntimeLang == RHS->getRuntimeLang() &&
612            VTableHolder == RHS->getRawVTableHolder() &&
613            TemplateParams == RHS->getRawTemplateParams() &&
614            Identifier == RHS->getRawIdentifier() &&
615            Discriminator == RHS->getRawDiscriminator() &&
616            DataLocation == RHS->getRawDataLocation() &&
617            Associated == RHS->getRawAssociated() &&
618            Allocated == RHS->getRawAllocated() && Rank == RHS->getRawRank();
619   }
620 
621   unsigned getHashValue() const {
622     // Intentionally computes the hash on a subset of the operands for
623     // performance reason. The subset has to be significant enough to avoid
624     // collision "most of the time". There is no correctness issue in case of
625     // collision because of the full check above.
626     return hash_combine(Name, File, Line, BaseType, Scope, Elements,
627                         TemplateParams);
628   }
629 };
630 
631 template <> struct MDNodeKeyImpl<DISubroutineType> {
632   unsigned Flags;
633   uint8_t CC;
634   Metadata *TypeArray;
635 
636   MDNodeKeyImpl(unsigned Flags, uint8_t CC, Metadata *TypeArray)
637       : Flags(Flags), CC(CC), TypeArray(TypeArray) {}
638   MDNodeKeyImpl(const DISubroutineType *N)
639       : Flags(N->getFlags()), CC(N->getCC()), TypeArray(N->getRawTypeArray()) {}
640 
641   bool isKeyOf(const DISubroutineType *RHS) const {
642     return Flags == RHS->getFlags() && CC == RHS->getCC() &&
643            TypeArray == RHS->getRawTypeArray();
644   }
645 
646   unsigned getHashValue() const { return hash_combine(Flags, CC, TypeArray); }
647 };
648 
649 template <> struct MDNodeKeyImpl<DIFile> {
650   MDString *Filename;
651   MDString *Directory;
652   Optional<DIFile::ChecksumInfo<MDString *>> Checksum;
653   Optional<MDString *> Source;
654 
655   MDNodeKeyImpl(MDString *Filename, MDString *Directory,
656                 Optional<DIFile::ChecksumInfo<MDString *>> Checksum,
657                 Optional<MDString *> Source)
658       : Filename(Filename), Directory(Directory), Checksum(Checksum),
659         Source(Source) {}
660   MDNodeKeyImpl(const DIFile *N)
661       : Filename(N->getRawFilename()), Directory(N->getRawDirectory()),
662         Checksum(N->getRawChecksum()), Source(N->getRawSource()) {}
663 
664   bool isKeyOf(const DIFile *RHS) const {
665     return Filename == RHS->getRawFilename() &&
666            Directory == RHS->getRawDirectory() &&
667            Checksum == RHS->getRawChecksum() &&
668            Source == RHS->getRawSource();
669   }
670 
671   unsigned getHashValue() const {
672     return hash_combine(
673         Filename, Directory, Checksum ? Checksum->Kind : 0,
674         Checksum ? Checksum->Value : nullptr, Source.getValueOr(nullptr));
675   }
676 };
677 
678 template <> struct MDNodeKeyImpl<DISubprogram> {
679   Metadata *Scope;
680   MDString *Name;
681   MDString *LinkageName;
682   Metadata *File;
683   unsigned Line;
684   Metadata *Type;
685   unsigned ScopeLine;
686   Metadata *ContainingType;
687   unsigned VirtualIndex;
688   int ThisAdjustment;
689   unsigned Flags;
690   unsigned SPFlags;
691   Metadata *Unit;
692   Metadata *TemplateParams;
693   Metadata *Declaration;
694   Metadata *RetainedNodes;
695   Metadata *ThrownTypes;
696 
697   MDNodeKeyImpl(Metadata *Scope, MDString *Name, MDString *LinkageName,
698                 Metadata *File, unsigned Line, Metadata *Type,
699                 unsigned ScopeLine, Metadata *ContainingType,
700                 unsigned VirtualIndex, int ThisAdjustment, unsigned Flags,
701                 unsigned SPFlags, Metadata *Unit, Metadata *TemplateParams,
702                 Metadata *Declaration, Metadata *RetainedNodes,
703                 Metadata *ThrownTypes)
704       : Scope(Scope), Name(Name), LinkageName(LinkageName), File(File),
705         Line(Line), Type(Type), ScopeLine(ScopeLine),
706         ContainingType(ContainingType), VirtualIndex(VirtualIndex),
707         ThisAdjustment(ThisAdjustment), Flags(Flags), SPFlags(SPFlags),
708         Unit(Unit), TemplateParams(TemplateParams), Declaration(Declaration),
709         RetainedNodes(RetainedNodes), ThrownTypes(ThrownTypes) {}
710   MDNodeKeyImpl(const DISubprogram *N)
711       : Scope(N->getRawScope()), Name(N->getRawName()),
712         LinkageName(N->getRawLinkageName()), File(N->getRawFile()),
713         Line(N->getLine()), Type(N->getRawType()), ScopeLine(N->getScopeLine()),
714         ContainingType(N->getRawContainingType()),
715         VirtualIndex(N->getVirtualIndex()),
716         ThisAdjustment(N->getThisAdjustment()), Flags(N->getFlags()),
717         SPFlags(N->getSPFlags()), Unit(N->getRawUnit()),
718         TemplateParams(N->getRawTemplateParams()),
719         Declaration(N->getRawDeclaration()),
720         RetainedNodes(N->getRawRetainedNodes()),
721         ThrownTypes(N->getRawThrownTypes()) {}
722 
723   bool isKeyOf(const DISubprogram *RHS) const {
724     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
725            LinkageName == RHS->getRawLinkageName() &&
726            File == RHS->getRawFile() && Line == RHS->getLine() &&
727            Type == RHS->getRawType() && ScopeLine == RHS->getScopeLine() &&
728            ContainingType == RHS->getRawContainingType() &&
729            VirtualIndex == RHS->getVirtualIndex() &&
730            ThisAdjustment == RHS->getThisAdjustment() &&
731            Flags == RHS->getFlags() && SPFlags == RHS->getSPFlags() &&
732            Unit == RHS->getUnit() &&
733            TemplateParams == RHS->getRawTemplateParams() &&
734            Declaration == RHS->getRawDeclaration() &&
735            RetainedNodes == RHS->getRawRetainedNodes() &&
736            ThrownTypes == RHS->getRawThrownTypes();
737   }
738 
739   bool isDefinition() const { return SPFlags & DISubprogram::SPFlagDefinition; }
740 
741   unsigned getHashValue() const {
742     // If this is a declaration inside an ODR type, only hash the type and the
743     // name.  Otherwise the hash will be stronger than
744     // MDNodeSubsetEqualImpl::isDeclarationOfODRMember().
745     if (!isDefinition() && LinkageName)
746       if (auto *CT = dyn_cast_or_null<DICompositeType>(Scope))
747         if (CT->getRawIdentifier())
748           return hash_combine(LinkageName, Scope);
749 
750     // Intentionally computes the hash on a subset of the operands for
751     // performance reason. The subset has to be significant enough to avoid
752     // collision "most of the time". There is no correctness issue in case of
753     // collision because of the full check above.
754     return hash_combine(Name, Scope, File, Type, Line);
755   }
756 };
757 
758 template <> struct MDNodeSubsetEqualImpl<DISubprogram> {
759   using KeyTy = MDNodeKeyImpl<DISubprogram>;
760 
761   static bool isSubsetEqual(const KeyTy &LHS, const DISubprogram *RHS) {
762     return isDeclarationOfODRMember(LHS.isDefinition(), LHS.Scope,
763                                     LHS.LinkageName, LHS.TemplateParams, RHS);
764   }
765 
766   static bool isSubsetEqual(const DISubprogram *LHS, const DISubprogram *RHS) {
767     return isDeclarationOfODRMember(LHS->isDefinition(), LHS->getRawScope(),
768                                     LHS->getRawLinkageName(),
769                                     LHS->getRawTemplateParams(), RHS);
770   }
771 
772   /// Subprograms compare equal if they declare the same function in an ODR
773   /// type.
774   static bool isDeclarationOfODRMember(bool IsDefinition, const Metadata *Scope,
775                                        const MDString *LinkageName,
776                                        const Metadata *TemplateParams,
777                                        const DISubprogram *RHS) {
778     // Check whether the LHS is eligible.
779     if (IsDefinition || !Scope || !LinkageName)
780       return false;
781 
782     auto *CT = dyn_cast_or_null<DICompositeType>(Scope);
783     if (!CT || !CT->getRawIdentifier())
784       return false;
785 
786     // Compare to the RHS.
787     // FIXME: We need to compare template parameters here to avoid incorrect
788     // collisions in mapMetadata when RF_ReuseAndMutateDistinctMDs and a
789     // ODR-DISubprogram has a non-ODR template parameter (i.e., a
790     // DICompositeType that does not have an identifier). Eventually we should
791     // decouple ODR logic from uniquing logic.
792     return IsDefinition == RHS->isDefinition() && Scope == RHS->getRawScope() &&
793            LinkageName == RHS->getRawLinkageName() &&
794            TemplateParams == RHS->getRawTemplateParams();
795   }
796 };
797 
798 template <> struct MDNodeKeyImpl<DILexicalBlock> {
799   Metadata *Scope;
800   Metadata *File;
801   unsigned Line;
802   unsigned Column;
803 
804   MDNodeKeyImpl(Metadata *Scope, Metadata *File, unsigned Line, unsigned Column)
805       : Scope(Scope), File(File), Line(Line), Column(Column) {}
806   MDNodeKeyImpl(const DILexicalBlock *N)
807       : Scope(N->getRawScope()), File(N->getRawFile()), Line(N->getLine()),
808         Column(N->getColumn()) {}
809 
810   bool isKeyOf(const DILexicalBlock *RHS) const {
811     return Scope == RHS->getRawScope() && File == RHS->getRawFile() &&
812            Line == RHS->getLine() && Column == RHS->getColumn();
813   }
814 
815   unsigned getHashValue() const {
816     return hash_combine(Scope, File, Line, Column);
817   }
818 };
819 
820 template <> struct MDNodeKeyImpl<DILexicalBlockFile> {
821   Metadata *Scope;
822   Metadata *File;
823   unsigned Discriminator;
824 
825   MDNodeKeyImpl(Metadata *Scope, Metadata *File, unsigned Discriminator)
826       : Scope(Scope), File(File), Discriminator(Discriminator) {}
827   MDNodeKeyImpl(const DILexicalBlockFile *N)
828       : Scope(N->getRawScope()), File(N->getRawFile()),
829         Discriminator(N->getDiscriminator()) {}
830 
831   bool isKeyOf(const DILexicalBlockFile *RHS) const {
832     return Scope == RHS->getRawScope() && File == RHS->getRawFile() &&
833            Discriminator == RHS->getDiscriminator();
834   }
835 
836   unsigned getHashValue() const {
837     return hash_combine(Scope, File, Discriminator);
838   }
839 };
840 
841 template <> struct MDNodeKeyImpl<DINamespace> {
842   Metadata *Scope;
843   MDString *Name;
844   bool ExportSymbols;
845 
846   MDNodeKeyImpl(Metadata *Scope, MDString *Name, bool ExportSymbols)
847       : Scope(Scope), Name(Name), ExportSymbols(ExportSymbols) {}
848   MDNodeKeyImpl(const DINamespace *N)
849       : Scope(N->getRawScope()), Name(N->getRawName()),
850         ExportSymbols(N->getExportSymbols()) {}
851 
852   bool isKeyOf(const DINamespace *RHS) const {
853     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
854            ExportSymbols == RHS->getExportSymbols();
855   }
856 
857   unsigned getHashValue() const {
858     return hash_combine(Scope, Name);
859   }
860 };
861 
862 template <> struct MDNodeKeyImpl<DICommonBlock> {
863   Metadata *Scope;
864   Metadata *Decl;
865   MDString *Name;
866   Metadata *File;
867   unsigned LineNo;
868 
869   MDNodeKeyImpl(Metadata *Scope, Metadata *Decl, MDString *Name,
870                 Metadata *File, unsigned LineNo)
871       : Scope(Scope), Decl(Decl), Name(Name), File(File), LineNo(LineNo) {}
872   MDNodeKeyImpl(const DICommonBlock *N)
873       : Scope(N->getRawScope()), Decl(N->getRawDecl()), Name(N->getRawName()),
874         File(N->getRawFile()), LineNo(N->getLineNo()) {}
875 
876   bool isKeyOf(const DICommonBlock *RHS) const {
877     return Scope == RHS->getRawScope() && Decl == RHS->getRawDecl() &&
878       Name == RHS->getRawName() && File == RHS->getRawFile() &&
879       LineNo == RHS->getLineNo();
880   }
881 
882   unsigned getHashValue() const {
883     return hash_combine(Scope, Decl, Name, File, LineNo);
884   }
885 };
886 
887 template <> struct MDNodeKeyImpl<DIModule> {
888   Metadata *File;
889   Metadata *Scope;
890   MDString *Name;
891   MDString *ConfigurationMacros;
892   MDString *IncludePath;
893   MDString *APINotesFile;
894   unsigned LineNo;
895   bool IsDecl;
896 
897   MDNodeKeyImpl(Metadata *File, Metadata *Scope, MDString *Name,
898                 MDString *ConfigurationMacros, MDString *IncludePath,
899                 MDString *APINotesFile, unsigned LineNo, bool IsDecl)
900       : File(File), Scope(Scope), Name(Name),
901         ConfigurationMacros(ConfigurationMacros), IncludePath(IncludePath),
902         APINotesFile(APINotesFile), LineNo(LineNo), IsDecl(IsDecl) {}
903   MDNodeKeyImpl(const DIModule *N)
904       : File(N->getRawFile()), Scope(N->getRawScope()), Name(N->getRawName()),
905         ConfigurationMacros(N->getRawConfigurationMacros()),
906         IncludePath(N->getRawIncludePath()),
907         APINotesFile(N->getRawAPINotesFile()), LineNo(N->getLineNo()),
908         IsDecl(N->getIsDecl()) {}
909 
910   bool isKeyOf(const DIModule *RHS) const {
911     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
912            ConfigurationMacros == RHS->getRawConfigurationMacros() &&
913            IncludePath == RHS->getRawIncludePath() &&
914            APINotesFile == RHS->getRawAPINotesFile() &&
915            File == RHS->getRawFile() && LineNo == RHS->getLineNo() &&
916            IsDecl == RHS->getIsDecl();
917   }
918 
919   unsigned getHashValue() const {
920     return hash_combine(Scope, Name, ConfigurationMacros, IncludePath);
921   }
922 };
923 
924 template <> struct MDNodeKeyImpl<DITemplateTypeParameter> {
925   MDString *Name;
926   Metadata *Type;
927   bool IsDefault;
928 
929   MDNodeKeyImpl(MDString *Name, Metadata *Type, bool IsDefault)
930       : Name(Name), Type(Type), IsDefault(IsDefault) {}
931   MDNodeKeyImpl(const DITemplateTypeParameter *N)
932       : Name(N->getRawName()), Type(N->getRawType()),
933         IsDefault(N->isDefault()) {}
934 
935   bool isKeyOf(const DITemplateTypeParameter *RHS) const {
936     return Name == RHS->getRawName() && Type == RHS->getRawType() &&
937            IsDefault == RHS->isDefault();
938   }
939 
940   unsigned getHashValue() const { return hash_combine(Name, Type, IsDefault); }
941 };
942 
943 template <> struct MDNodeKeyImpl<DITemplateValueParameter> {
944   unsigned Tag;
945   MDString *Name;
946   Metadata *Type;
947   bool IsDefault;
948   Metadata *Value;
949 
950   MDNodeKeyImpl(unsigned Tag, MDString *Name, Metadata *Type, bool IsDefault,
951                 Metadata *Value)
952       : Tag(Tag), Name(Name), Type(Type), IsDefault(IsDefault), Value(Value) {}
953   MDNodeKeyImpl(const DITemplateValueParameter *N)
954       : Tag(N->getTag()), Name(N->getRawName()), Type(N->getRawType()),
955         IsDefault(N->isDefault()), Value(N->getValue()) {}
956 
957   bool isKeyOf(const DITemplateValueParameter *RHS) const {
958     return Tag == RHS->getTag() && Name == RHS->getRawName() &&
959            Type == RHS->getRawType() && IsDefault == RHS->isDefault() &&
960            Value == RHS->getValue();
961   }
962 
963   unsigned getHashValue() const {
964     return hash_combine(Tag, Name, Type, IsDefault, Value);
965   }
966 };
967 
968 template <> struct MDNodeKeyImpl<DIGlobalVariable> {
969   Metadata *Scope;
970   MDString *Name;
971   MDString *LinkageName;
972   Metadata *File;
973   unsigned Line;
974   Metadata *Type;
975   bool IsLocalToUnit;
976   bool IsDefinition;
977   Metadata *StaticDataMemberDeclaration;
978   Metadata *TemplateParams;
979   uint32_t AlignInBits;
980 
981   MDNodeKeyImpl(Metadata *Scope, MDString *Name, MDString *LinkageName,
982                 Metadata *File, unsigned Line, Metadata *Type,
983                 bool IsLocalToUnit, bool IsDefinition,
984                 Metadata *StaticDataMemberDeclaration, Metadata *TemplateParams,
985                 uint32_t AlignInBits)
986       : Scope(Scope), Name(Name), LinkageName(LinkageName), File(File),
987         Line(Line), Type(Type), IsLocalToUnit(IsLocalToUnit),
988         IsDefinition(IsDefinition),
989         StaticDataMemberDeclaration(StaticDataMemberDeclaration),
990         TemplateParams(TemplateParams), AlignInBits(AlignInBits) {}
991   MDNodeKeyImpl(const DIGlobalVariable *N)
992       : Scope(N->getRawScope()), Name(N->getRawName()),
993         LinkageName(N->getRawLinkageName()), File(N->getRawFile()),
994         Line(N->getLine()), Type(N->getRawType()),
995         IsLocalToUnit(N->isLocalToUnit()), IsDefinition(N->isDefinition()),
996         StaticDataMemberDeclaration(N->getRawStaticDataMemberDeclaration()),
997         TemplateParams(N->getRawTemplateParams()),
998         AlignInBits(N->getAlignInBits()) {}
999 
1000   bool isKeyOf(const DIGlobalVariable *RHS) const {
1001     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
1002            LinkageName == RHS->getRawLinkageName() &&
1003            File == RHS->getRawFile() && Line == RHS->getLine() &&
1004            Type == RHS->getRawType() && IsLocalToUnit == RHS->isLocalToUnit() &&
1005            IsDefinition == RHS->isDefinition() &&
1006            StaticDataMemberDeclaration ==
1007                RHS->getRawStaticDataMemberDeclaration() &&
1008            TemplateParams == RHS->getRawTemplateParams() &&
1009            AlignInBits == RHS->getAlignInBits();
1010   }
1011 
1012   unsigned getHashValue() const {
1013     // We do not use AlignInBits in hashing function here on purpose:
1014     // in most cases this param for local variable is zero (for function param
1015     // it is always zero). This leads to lots of hash collisions and errors on
1016     // cases with lots of similar variables.
1017     // clang/test/CodeGen/debug-info-257-args.c is an example of this problem,
1018     // generated IR is random for each run and test fails with Align included.
1019     // TODO: make hashing work fine with such situations
1020     return hash_combine(Scope, Name, LinkageName, File, Line, Type,
1021                         IsLocalToUnit, IsDefinition, /* AlignInBits, */
1022                         StaticDataMemberDeclaration);
1023   }
1024 };
1025 
1026 template <> struct MDNodeKeyImpl<DILocalVariable> {
1027   Metadata *Scope;
1028   MDString *Name;
1029   Metadata *File;
1030   unsigned Line;
1031   Metadata *Type;
1032   unsigned Arg;
1033   unsigned Flags;
1034   uint32_t AlignInBits;
1035 
1036   MDNodeKeyImpl(Metadata *Scope, MDString *Name, Metadata *File, unsigned Line,
1037                 Metadata *Type, unsigned Arg, unsigned Flags,
1038                 uint32_t AlignInBits)
1039       : Scope(Scope), Name(Name), File(File), Line(Line), Type(Type), Arg(Arg),
1040         Flags(Flags), AlignInBits(AlignInBits) {}
1041   MDNodeKeyImpl(const DILocalVariable *N)
1042       : Scope(N->getRawScope()), Name(N->getRawName()), File(N->getRawFile()),
1043         Line(N->getLine()), Type(N->getRawType()), Arg(N->getArg()),
1044         Flags(N->getFlags()), AlignInBits(N->getAlignInBits()) {}
1045 
1046   bool isKeyOf(const DILocalVariable *RHS) const {
1047     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
1048            File == RHS->getRawFile() && Line == RHS->getLine() &&
1049            Type == RHS->getRawType() && Arg == RHS->getArg() &&
1050            Flags == RHS->getFlags() && AlignInBits == RHS->getAlignInBits();
1051   }
1052 
1053   unsigned getHashValue() const {
1054     // We do not use AlignInBits in hashing function here on purpose:
1055     // in most cases this param for local variable is zero (for function param
1056     // it is always zero). This leads to lots of hash collisions and errors on
1057     // cases with lots of similar variables.
1058     // clang/test/CodeGen/debug-info-257-args.c is an example of this problem,
1059     // generated IR is random for each run and test fails with Align included.
1060     // TODO: make hashing work fine with such situations
1061     return hash_combine(Scope, Name, File, Line, Type, Arg, Flags);
1062   }
1063 };
1064 
1065 template <> struct MDNodeKeyImpl<DILabel> {
1066   Metadata *Scope;
1067   MDString *Name;
1068   Metadata *File;
1069   unsigned Line;
1070 
1071   MDNodeKeyImpl(Metadata *Scope, MDString *Name, Metadata *File, unsigned Line)
1072       : Scope(Scope), Name(Name), File(File), Line(Line) {}
1073   MDNodeKeyImpl(const DILabel *N)
1074       : Scope(N->getRawScope()), Name(N->getRawName()), File(N->getRawFile()),
1075         Line(N->getLine()) {}
1076 
1077   bool isKeyOf(const DILabel *RHS) const {
1078     return Scope == RHS->getRawScope() && Name == RHS->getRawName() &&
1079            File == RHS->getRawFile() && Line == RHS->getLine();
1080   }
1081 
1082   /// Using name and line to get hash value. It should already be mostly unique.
1083   unsigned getHashValue() const {
1084     return hash_combine(Scope, Name, Line);
1085   }
1086 };
1087 
1088 template <> struct MDNodeKeyImpl<DIExpression> {
1089   ArrayRef<uint64_t> Elements;
1090 
1091   MDNodeKeyImpl(ArrayRef<uint64_t> Elements) : Elements(Elements) {}
1092   MDNodeKeyImpl(const DIExpression *N) : Elements(N->getElements()) {}
1093 
1094   bool isKeyOf(const DIExpression *RHS) const {
1095     return Elements == RHS->getElements();
1096   }
1097 
1098   unsigned getHashValue() const {
1099     return hash_combine_range(Elements.begin(), Elements.end());
1100   }
1101 };
1102 
1103 template <> struct MDNodeKeyImpl<DIGlobalVariableExpression> {
1104   Metadata *Variable;
1105   Metadata *Expression;
1106 
1107   MDNodeKeyImpl(Metadata *Variable, Metadata *Expression)
1108       : Variable(Variable), Expression(Expression) {}
1109   MDNodeKeyImpl(const DIGlobalVariableExpression *N)
1110       : Variable(N->getRawVariable()), Expression(N->getRawExpression()) {}
1111 
1112   bool isKeyOf(const DIGlobalVariableExpression *RHS) const {
1113     return Variable == RHS->getRawVariable() &&
1114            Expression == RHS->getRawExpression();
1115   }
1116 
1117   unsigned getHashValue() const { return hash_combine(Variable, Expression); }
1118 };
1119 
1120 template <> struct MDNodeKeyImpl<DIObjCProperty> {
1121   MDString *Name;
1122   Metadata *File;
1123   unsigned Line;
1124   MDString *GetterName;
1125   MDString *SetterName;
1126   unsigned Attributes;
1127   Metadata *Type;
1128 
1129   MDNodeKeyImpl(MDString *Name, Metadata *File, unsigned Line,
1130                 MDString *GetterName, MDString *SetterName, unsigned Attributes,
1131                 Metadata *Type)
1132       : Name(Name), File(File), Line(Line), GetterName(GetterName),
1133         SetterName(SetterName), Attributes(Attributes), Type(Type) {}
1134   MDNodeKeyImpl(const DIObjCProperty *N)
1135       : Name(N->getRawName()), File(N->getRawFile()), Line(N->getLine()),
1136         GetterName(N->getRawGetterName()), SetterName(N->getRawSetterName()),
1137         Attributes(N->getAttributes()), Type(N->getRawType()) {}
1138 
1139   bool isKeyOf(const DIObjCProperty *RHS) const {
1140     return Name == RHS->getRawName() && File == RHS->getRawFile() &&
1141            Line == RHS->getLine() && GetterName == RHS->getRawGetterName() &&
1142            SetterName == RHS->getRawSetterName() &&
1143            Attributes == RHS->getAttributes() && Type == RHS->getRawType();
1144   }
1145 
1146   unsigned getHashValue() const {
1147     return hash_combine(Name, File, Line, GetterName, SetterName, Attributes,
1148                         Type);
1149   }
1150 };
1151 
1152 template <> struct MDNodeKeyImpl<DIImportedEntity> {
1153   unsigned Tag;
1154   Metadata *Scope;
1155   Metadata *Entity;
1156   Metadata *File;
1157   unsigned Line;
1158   MDString *Name;
1159 
1160   MDNodeKeyImpl(unsigned Tag, Metadata *Scope, Metadata *Entity, Metadata *File,
1161                 unsigned Line, MDString *Name)
1162       : Tag(Tag), Scope(Scope), Entity(Entity), File(File), Line(Line),
1163         Name(Name) {}
1164   MDNodeKeyImpl(const DIImportedEntity *N)
1165       : Tag(N->getTag()), Scope(N->getRawScope()), Entity(N->getRawEntity()),
1166         File(N->getRawFile()), Line(N->getLine()), Name(N->getRawName()) {}
1167 
1168   bool isKeyOf(const DIImportedEntity *RHS) const {
1169     return Tag == RHS->getTag() && Scope == RHS->getRawScope() &&
1170            Entity == RHS->getRawEntity() && File == RHS->getFile() &&
1171            Line == RHS->getLine() && Name == RHS->getRawName();
1172   }
1173 
1174   unsigned getHashValue() const {
1175     return hash_combine(Tag, Scope, Entity, File, Line, Name);
1176   }
1177 };
1178 
1179 template <> struct MDNodeKeyImpl<DIMacro> {
1180   unsigned MIType;
1181   unsigned Line;
1182   MDString *Name;
1183   MDString *Value;
1184 
1185   MDNodeKeyImpl(unsigned MIType, unsigned Line, MDString *Name, MDString *Value)
1186       : MIType(MIType), Line(Line), Name(Name), Value(Value) {}
1187   MDNodeKeyImpl(const DIMacro *N)
1188       : MIType(N->getMacinfoType()), Line(N->getLine()), Name(N->getRawName()),
1189         Value(N->getRawValue()) {}
1190 
1191   bool isKeyOf(const DIMacro *RHS) const {
1192     return MIType == RHS->getMacinfoType() && Line == RHS->getLine() &&
1193            Name == RHS->getRawName() && Value == RHS->getRawValue();
1194   }
1195 
1196   unsigned getHashValue() const {
1197     return hash_combine(MIType, Line, Name, Value);
1198   }
1199 };
1200 
1201 template <> struct MDNodeKeyImpl<DIMacroFile> {
1202   unsigned MIType;
1203   unsigned Line;
1204   Metadata *File;
1205   Metadata *Elements;
1206 
1207   MDNodeKeyImpl(unsigned MIType, unsigned Line, Metadata *File,
1208                 Metadata *Elements)
1209       : MIType(MIType), Line(Line), File(File), Elements(Elements) {}
1210   MDNodeKeyImpl(const DIMacroFile *N)
1211       : MIType(N->getMacinfoType()), Line(N->getLine()), File(N->getRawFile()),
1212         Elements(N->getRawElements()) {}
1213 
1214   bool isKeyOf(const DIMacroFile *RHS) const {
1215     return MIType == RHS->getMacinfoType() && Line == RHS->getLine() &&
1216            File == RHS->getRawFile() && Elements == RHS->getRawElements();
1217   }
1218 
1219   unsigned getHashValue() const {
1220     return hash_combine(MIType, Line, File, Elements);
1221   }
1222 };
1223 
1224 template <> struct MDNodeKeyImpl<DIArgList> {
1225   ArrayRef<ValueAsMetadata *> Args;
1226 
1227   MDNodeKeyImpl(ArrayRef<ValueAsMetadata *> Args) : Args(Args) {}
1228   MDNodeKeyImpl(const DIArgList *N) : Args(N->getArgs()) {}
1229 
1230   bool isKeyOf(const DIArgList *RHS) const { return Args == RHS->getArgs(); }
1231 
1232   unsigned getHashValue() const {
1233     return hash_combine_range(Args.begin(), Args.end());
1234   }
1235 };
1236 
1237 /// DenseMapInfo for MDNode subclasses.
1238 template <class NodeTy> struct MDNodeInfo {
1239   using KeyTy = MDNodeKeyImpl<NodeTy>;
1240   using SubsetEqualTy = MDNodeSubsetEqualImpl<NodeTy>;
1241 
1242   static inline NodeTy *getEmptyKey() {
1243     return DenseMapInfo<NodeTy *>::getEmptyKey();
1244   }
1245 
1246   static inline NodeTy *getTombstoneKey() {
1247     return DenseMapInfo<NodeTy *>::getTombstoneKey();
1248   }
1249 
1250   static unsigned getHashValue(const KeyTy &Key) { return Key.getHashValue(); }
1251 
1252   static unsigned getHashValue(const NodeTy *N) {
1253     return KeyTy(N).getHashValue();
1254   }
1255 
1256   static bool isEqual(const KeyTy &LHS, const NodeTy *RHS) {
1257     if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1258       return false;
1259     return SubsetEqualTy::isSubsetEqual(LHS, RHS) || LHS.isKeyOf(RHS);
1260   }
1261 
1262   static bool isEqual(const NodeTy *LHS, const NodeTy *RHS) {
1263     if (LHS == RHS)
1264       return true;
1265     if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1266       return false;
1267     return SubsetEqualTy::isSubsetEqual(LHS, RHS);
1268   }
1269 };
1270 
1271 #define HANDLE_MDNODE_LEAF(CLASS) using CLASS##Info = MDNodeInfo<CLASS>;
1272 #include "llvm/IR/Metadata.def"
1273 
1274 /// Multimap-like storage for metadata attachments.
1275 class MDAttachments {
1276 public:
1277   struct Attachment {
1278     unsigned MDKind;
1279     TrackingMDNodeRef Node;
1280   };
1281 
1282 private:
1283   SmallVector<Attachment, 1> Attachments;
1284 
1285 public:
1286   bool empty() const { return Attachments.empty(); }
1287   size_t size() const { return Attachments.size(); }
1288 
1289   /// Returns the first attachment with the given ID or nullptr if no such
1290   /// attachment exists.
1291   MDNode *lookup(unsigned ID) const;
1292 
1293   /// Appends all attachments with the given ID to \c Result in insertion order.
1294   /// If the global has no attachments with the given ID, or if ID is invalid,
1295   /// leaves Result unchanged.
1296   void get(unsigned ID, SmallVectorImpl<MDNode *> &Result) const;
1297 
1298   /// Appends all attachments for the global to \c Result, sorting by attachment
1299   /// ID. Attachments with the same ID appear in insertion order. This function
1300   /// does \em not clear \c Result.
1301   void getAll(SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const;
1302 
1303   /// Set an attachment to a particular node.
1304   ///
1305   /// Set the \c ID attachment to \c MD, replacing the current attachments at \c
1306   /// ID (if anyway).
1307   void set(unsigned ID, MDNode *MD);
1308 
1309   /// Adds an attachment to a particular node.
1310   void insert(unsigned ID, MDNode &MD);
1311 
1312   /// Remove attachments with the given ID.
1313   ///
1314   /// Remove the attachments at \c ID, if any.
1315   bool erase(unsigned ID);
1316 
1317   /// Erase matching attachments.
1318   ///
1319   /// Erases all attachments matching the \c shouldRemove predicate.
1320   template <class PredTy> void remove_if(PredTy shouldRemove) {
1321     llvm::erase_if(Attachments, shouldRemove);
1322   }
1323 };
1324 
1325 class LLVMContextImpl {
1326 public:
1327   /// OwnedModules - The set of modules instantiated in this context, and which
1328   /// will be automatically deleted if this context is deleted.
1329   SmallPtrSet<Module*, 4> OwnedModules;
1330 
1331   /// The main remark streamer used by all the other streamers (e.g. IR, MIR,
1332   /// frontends, etc.). This should only be used by the specific streamers, and
1333   /// never directly.
1334   std::unique_ptr<remarks::RemarkStreamer> MainRemarkStreamer;
1335 
1336   std::unique_ptr<DiagnosticHandler> DiagHandler;
1337   bool RespectDiagnosticFilters = false;
1338   bool DiagnosticsHotnessRequested = false;
1339   /// The minimum hotness value a diagnostic needs in order to be included in
1340   /// optimization diagnostics.
1341   ///
1342   /// The threshold is an Optional value, which maps to one of the 3 states:
1343   /// 1). 0            => threshold disabled. All emarks will be printed.
1344   /// 2). positive int => manual threshold by user. Remarks with hotness exceed
1345   ///                     threshold will be printed.
1346   /// 3). None         => 'auto' threshold by user. The actual value is not
1347   ///                     available at command line, but will be synced with
1348   ///                     hotness threhold from profile summary during
1349   ///                     compilation.
1350   ///
1351   /// State 1 and 2 are considered as terminal states. State transition is
1352   /// only allowed from 3 to 2, when the threshold is first synced with profile
1353   /// summary. This ensures that the threshold is set only once and stays
1354   /// constant.
1355   ///
1356   /// If threshold option is not specified, it is disabled (0) by default.
1357   Optional<uint64_t> DiagnosticsHotnessThreshold = 0;
1358 
1359   /// The specialized remark streamer used by LLVM's OptimizationRemarkEmitter.
1360   std::unique_ptr<LLVMRemarkStreamer> LLVMRS;
1361 
1362   LLVMContext::YieldCallbackTy YieldCallback = nullptr;
1363   void *YieldOpaqueHandle = nullptr;
1364 
1365   using IntMapTy =
1366       DenseMap<APInt, std::unique_ptr<ConstantInt>, DenseMapAPIntKeyInfo>;
1367   IntMapTy IntConstants;
1368 
1369   using FPMapTy =
1370       DenseMap<APFloat, std::unique_ptr<ConstantFP>, DenseMapAPFloatKeyInfo>;
1371   FPMapTy FPConstants;
1372 
1373   FoldingSet<AttributeImpl> AttrsSet;
1374   FoldingSet<AttributeListImpl> AttrsLists;
1375   FoldingSet<AttributeSetNode> AttrsSetNodes;
1376 
1377   StringMap<MDString, BumpPtrAllocator> MDStringCache;
1378   DenseMap<Value *, ValueAsMetadata *> ValuesAsMetadata;
1379   DenseMap<Metadata *, MetadataAsValue *> MetadataAsValues;
1380 
1381   DenseMap<const Value*, ValueName*> ValueNames;
1382 
1383 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
1384   DenseSet<CLASS *, CLASS##Info> CLASS##s;
1385 #include "llvm/IR/Metadata.def"
1386 
1387   // Optional map for looking up composite types by identifier.
1388   Optional<DenseMap<const MDString *, DICompositeType *>> DITypeMap;
1389 
1390   // MDNodes may be uniqued or not uniqued.  When they're not uniqued, they
1391   // aren't in the MDNodeSet, but they're still shared between objects, so no
1392   // one object can destroy them.  Keep track of them here so we can delete
1393   // them on context teardown.
1394   std::vector<MDNode *> DistinctMDNodes;
1395 
1396   DenseMap<Type *, std::unique_ptr<ConstantAggregateZero>> CAZConstants;
1397 
1398   using ArrayConstantsTy = ConstantUniqueMap<ConstantArray>;
1399   ArrayConstantsTy ArrayConstants;
1400 
1401   using StructConstantsTy = ConstantUniqueMap<ConstantStruct>;
1402   StructConstantsTy StructConstants;
1403 
1404   using VectorConstantsTy = ConstantUniqueMap<ConstantVector>;
1405   VectorConstantsTy VectorConstants;
1406 
1407   DenseMap<PointerType *, std::unique_ptr<ConstantPointerNull>> CPNConstants;
1408 
1409   DenseMap<Type *, std::unique_ptr<UndefValue>> UVConstants;
1410 
1411   DenseMap<Type *, std::unique_ptr<PoisonValue>> PVConstants;
1412 
1413   StringMap<std::unique_ptr<ConstantDataSequential>> CDSConstants;
1414 
1415   DenseMap<std::pair<const Function *, const BasicBlock *>, BlockAddress *>
1416     BlockAddresses;
1417 
1418   DenseMap<const GlobalValue *, DSOLocalEquivalent *> DSOLocalEquivalents;
1419 
1420   ConstantUniqueMap<ConstantExpr> ExprConstants;
1421 
1422   ConstantUniqueMap<InlineAsm> InlineAsms;
1423 
1424   ConstantInt *TheTrueVal = nullptr;
1425   ConstantInt *TheFalseVal = nullptr;
1426 
1427   std::unique_ptr<ConstantTokenNone> TheNoneToken;
1428 
1429   // Basic type instances.
1430   Type VoidTy, LabelTy, HalfTy, BFloatTy, FloatTy, DoubleTy, MetadataTy,
1431       TokenTy;
1432   Type X86_FP80Ty, FP128Ty, PPC_FP128Ty, X86_MMXTy, X86_AMXTy;
1433   IntegerType Int1Ty, Int8Ty, Int16Ty, Int32Ty, Int64Ty, Int128Ty;
1434 
1435   BumpPtrAllocator Alloc;
1436   UniqueStringSaver Saver{Alloc};
1437 
1438   DenseMap<unsigned, IntegerType*> IntegerTypes;
1439 
1440   using FunctionTypeSet = DenseSet<FunctionType *, FunctionTypeKeyInfo>;
1441   FunctionTypeSet FunctionTypes;
1442   using StructTypeSet = DenseSet<StructType *, AnonStructTypeKeyInfo>;
1443   StructTypeSet AnonStructTypes;
1444   StringMap<StructType*> NamedStructTypes;
1445   unsigned NamedStructTypesUniqueID = 0;
1446 
1447   DenseMap<std::pair<Type *, uint64_t>, ArrayType*> ArrayTypes;
1448   DenseMap<std::pair<Type *, ElementCount>, VectorType*> VectorTypes;
1449   // TODO: clean up the following after we no longer support non-opaque pointer
1450   // types.
1451   bool ForceOpaquePointers;
1452   DenseMap<Type*, PointerType*> PointerTypes;  // Pointers in AddrSpace = 0
1453   DenseMap<std::pair<Type*, unsigned>, PointerType*> ASPointerTypes;
1454 
1455   /// ValueHandles - This map keeps track of all of the value handles that are
1456   /// watching a Value*.  The Value::HasValueHandle bit is used to know
1457   /// whether or not a value has an entry in this map.
1458   using ValueHandlesTy = DenseMap<Value *, ValueHandleBase *>;
1459   ValueHandlesTy ValueHandles;
1460 
1461   /// CustomMDKindNames - Map to hold the metadata string to ID mapping.
1462   StringMap<unsigned> CustomMDKindNames;
1463 
1464   /// Collection of metadata used in this context.
1465   DenseMap<const Value *, MDAttachments> ValueMetadata;
1466 
1467   /// Collection of per-GlobalObject sections used in this context.
1468   DenseMap<const GlobalObject *, StringRef> GlobalObjectSections;
1469 
1470   /// Collection of per-GlobalValue partitions used in this context.
1471   DenseMap<const GlobalValue *, StringRef> GlobalValuePartitions;
1472 
1473   /// DiscriminatorTable - This table maps file:line locations to an
1474   /// integer representing the next DWARF path discriminator to assign to
1475   /// instructions in different blocks at the same location.
1476   DenseMap<std::pair<const char *, unsigned>, unsigned> DiscriminatorTable;
1477 
1478   /// A set of interned tags for operand bundles.  The StringMap maps
1479   /// bundle tags to their IDs.
1480   ///
1481   /// \see LLVMContext::getOperandBundleTagID
1482   StringMap<uint32_t> BundleTagCache;
1483 
1484   StringMapEntry<uint32_t> *getOrInsertBundleTag(StringRef Tag);
1485   void getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const;
1486   uint32_t getOperandBundleTagID(StringRef Tag) const;
1487 
1488   /// A set of interned synchronization scopes.  The StringMap maps
1489   /// synchronization scope names to their respective synchronization scope IDs.
1490   StringMap<SyncScope::ID> SSC;
1491 
1492   /// getOrInsertSyncScopeID - Maps synchronization scope name to
1493   /// synchronization scope ID.  Every synchronization scope registered with
1494   /// LLVMContext has unique ID except pre-defined ones.
1495   SyncScope::ID getOrInsertSyncScopeID(StringRef SSN);
1496 
1497   /// getSyncScopeNames - Populates client supplied SmallVector with
1498   /// synchronization scope names registered with LLVMContext.  Synchronization
1499   /// scope names are ordered by increasing synchronization scope IDs.
1500   void getSyncScopeNames(SmallVectorImpl<StringRef> &SSNs) const;
1501 
1502   /// Maintain the GC name for each function.
1503   ///
1504   /// This saves allocating an additional word in Function for programs which
1505   /// do not use GC (i.e., most programs) at the cost of increased overhead for
1506   /// clients which do use GC.
1507   DenseMap<const Function*, std::string> GCNames;
1508 
1509   /// Flag to indicate if Value (other than GlobalValue) retains their name or
1510   /// not.
1511   bool DiscardValueNames = false;
1512 
1513   LLVMContextImpl(LLVMContext &C);
1514   ~LLVMContextImpl();
1515 
1516   /// Destroy the ConstantArrays if they are not used.
1517   void dropTriviallyDeadConstantArrays();
1518 
1519   mutable OptPassGate *OPG = nullptr;
1520 
1521   /// Access the object which can disable optional passes and individual
1522   /// optimizations at compile time.
1523   OptPassGate &getOptPassGate() const;
1524 
1525   /// Set the object which can disable optional passes and individual
1526   /// optimizations at compile time.
1527   ///
1528   /// The lifetime of the object must be guaranteed to extend as long as the
1529   /// LLVMContext is used by compilation.
1530   void setOptPassGate(OptPassGate&);
1531 };
1532 
1533 } // end namespace llvm
1534 
1535 #endif // LLVM_LIB_IR_LLVMCONTEXTIMPL_H
1536