IdentifierTable.cpp revision 296417 
1//===--- IdentifierTable.cpp - Hash table for identifier lookup -----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the IdentifierInfo, IdentifierVisitor, and
11// IdentifierTable interfaces.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/Basic/CharInfo.h"
16#include "clang/Basic/IdentifierTable.h"
17#include "clang/Basic/LangOptions.h"
18#include "clang/Basic/OperatorKinds.h"
19#include "clang/Basic/Specifiers.h"
20#include "llvm/ADT/DenseMap.h"
21#include "llvm/ADT/FoldingSet.h"
22#include "llvm/ADT/SmallString.h"
23#include "llvm/Support/ErrorHandling.h"
24#include "llvm/Support/raw_ostream.h"
25#include <cstdio>
26
27using namespace clang;
28
29//===----------------------------------------------------------------------===//
30// IdentifierInfo Implementation
31//===----------------------------------------------------------------------===//
32
33IdentifierInfo::IdentifierInfo() {
34  TokenID = tok::identifier;
35  ObjCOrBuiltinID = 0;
36  HasMacro = false;
37  HadMacro = false;
38  IsExtension = false;
39  IsFutureCompatKeyword = false;
40  IsPoisoned = false;
41  IsCPPOperatorKeyword = false;
42  NeedsHandleIdentifier = false;
43  IsFromAST = false;
44  ChangedAfterLoad = false;
45  RevertedTokenID = false;
46  OutOfDate = false;
47  IsModulesImport = false;
48  FETokenInfo = nullptr;
49  Entry = nullptr;
50}
51
52//===----------------------------------------------------------------------===//
53// IdentifierTable Implementation
54//===----------------------------------------------------------------------===//
55
56IdentifierIterator::~IdentifierIterator() { }
57
58IdentifierInfoLookup::~IdentifierInfoLookup() {}
59
60namespace {
61  /// \brief A simple identifier lookup iterator that represents an
62  /// empty sequence of identifiers.
63  class EmptyLookupIterator : public IdentifierIterator
64  {
65  public:
66    StringRef Next() override { return StringRef(); }
67  };
68}
69
70IdentifierIterator *IdentifierInfoLookup::getIdentifiers() {
71  return new EmptyLookupIterator();
72}
73
74IdentifierTable::IdentifierTable(const LangOptions &LangOpts,
75                                 IdentifierInfoLookup* externalLookup)
76  : HashTable(8192), // Start with space for 8K identifiers.
77    ExternalLookup(externalLookup) {
78
79  // Populate the identifier table with info about keywords for the current
80  // language.
81  AddKeywords(LangOpts);
82
83
84  // Add the '_experimental_modules_import' contextual keyword.
85  get("import").setModulesImport(true);
86}
87
88//===----------------------------------------------------------------------===//
89// Language Keyword Implementation
90//===----------------------------------------------------------------------===//
91
92// Constants for TokenKinds.def
93namespace {
94  enum {
95    KEYC99 = 0x1,
96    KEYCXX = 0x2,
97    KEYCXX11 = 0x4,
98    KEYGNU = 0x8,
99    KEYMS = 0x10,
100    BOOLSUPPORT = 0x20,
101    KEYALTIVEC = 0x40,
102    KEYNOCXX = 0x80,
103    KEYBORLAND = 0x100,
104    KEYOPENCL = 0x200,
105    KEYC11 = 0x400,
106    KEYARC = 0x800,
107    KEYNOMS18 = 0x01000,
108    KEYNOOPENCL = 0x02000,
109    WCHARSUPPORT = 0x04000,
110    HALFSUPPORT = 0x08000,
111    KEYCONCEPTS = 0x10000,
112    KEYOBJC2    = 0x20000,
113    KEYZVECTOR  = 0x40000,
114    KEYCOROUTINES = 0x80000,
115    KEYALL = (0xfffff & ~KEYNOMS18 &
116              ~KEYNOOPENCL) // KEYNOMS18 and KEYNOOPENCL are used to exclude.
117  };
118
119  /// \brief How a keyword is treated in the selected standard.
120  enum KeywordStatus {
121    KS_Disabled,    // Disabled
122    KS_Extension,   // Is an extension
123    KS_Enabled,     // Enabled
124    KS_Future       // Is a keyword in future standard
125  };
126}
127
128/// \brief Translates flags as specified in TokenKinds.def into keyword status
129/// in the given language standard.
130static KeywordStatus getKeywordStatus(const LangOptions &LangOpts,
131                                      unsigned Flags) {
132  if (Flags == KEYALL) return KS_Enabled;
133  if (LangOpts.CPlusPlus && (Flags & KEYCXX)) return KS_Enabled;
134  if (LangOpts.CPlusPlus11 && (Flags & KEYCXX11)) return KS_Enabled;
135  if (LangOpts.C99 && (Flags & KEYC99)) return KS_Enabled;
136  if (LangOpts.GNUKeywords && (Flags & KEYGNU)) return KS_Extension;
137  if (LangOpts.MicrosoftExt && (Flags & KEYMS)) return KS_Extension;
138  if (LangOpts.Borland && (Flags & KEYBORLAND)) return KS_Extension;
139  if (LangOpts.Bool && (Flags & BOOLSUPPORT)) return KS_Enabled;
140  if (LangOpts.Half && (Flags & HALFSUPPORT)) return KS_Enabled;
141  if (LangOpts.WChar && (Flags & WCHARSUPPORT)) return KS_Enabled;
142  if (LangOpts.AltiVec && (Flags & KEYALTIVEC)) return KS_Enabled;
143  if (LangOpts.OpenCL && (Flags & KEYOPENCL)) return KS_Enabled;
144  if (!LangOpts.CPlusPlus && (Flags & KEYNOCXX)) return KS_Enabled;
145  if (LangOpts.C11 && (Flags & KEYC11)) return KS_Enabled;
146  // We treat bridge casts as objective-C keywords so we can warn on them
147  // in non-arc mode.
148  if (LangOpts.ObjC2 && (Flags & KEYARC)) return KS_Enabled;
149  if (LangOpts.ConceptsTS && (Flags & KEYCONCEPTS)) return KS_Enabled;
150  if (LangOpts.ObjC2 && (Flags & KEYOBJC2)) return KS_Enabled;
151  if (LangOpts.Coroutines && (Flags & KEYCOROUTINES)) return KS_Enabled;
152  if (LangOpts.CPlusPlus && (Flags & KEYCXX11)) return KS_Future;
153  return KS_Disabled;
154}
155
156/// AddKeyword - This method is used to associate a token ID with specific
157/// identifiers because they are language keywords.  This causes the lexer to
158/// automatically map matching identifiers to specialized token codes.
159static void AddKeyword(StringRef Keyword,
160                       tok::TokenKind TokenCode, unsigned Flags,
161                       const LangOptions &LangOpts, IdentifierTable &Table) {
162  KeywordStatus AddResult = getKeywordStatus(LangOpts, Flags);
163
164  // Don't add this keyword under MSVCCompat.
165  if (LangOpts.MSVCCompat && (Flags & KEYNOMS18) &&
166      !LangOpts.isCompatibleWithMSVC(LangOptions::MSVC2015))
167    return;
168
169  // Don't add this keyword under OpenCL.
170  if (LangOpts.OpenCL && (Flags & KEYNOOPENCL))
171    return;
172
173  // Don't add this keyword if disabled in this language.
174  if (AddResult == KS_Disabled) return;
175
176  IdentifierInfo &Info =
177      Table.get(Keyword, AddResult == KS_Future ? tok::identifier : TokenCode);
178  Info.setIsExtensionToken(AddResult == KS_Extension);
179  Info.setIsFutureCompatKeyword(AddResult == KS_Future);
180}
181
182/// AddCXXOperatorKeyword - Register a C++ operator keyword alternative
183/// representations.
184static void AddCXXOperatorKeyword(StringRef Keyword,
185                                  tok::TokenKind TokenCode,
186                                  IdentifierTable &Table) {
187  IdentifierInfo &Info = Table.get(Keyword, TokenCode);
188  Info.setIsCPlusPlusOperatorKeyword();
189}
190
191/// AddObjCKeyword - Register an Objective-C \@keyword like "class" "selector"
192/// or "property".
193static void AddObjCKeyword(StringRef Name,
194                           tok::ObjCKeywordKind ObjCID,
195                           IdentifierTable &Table) {
196  Table.get(Name).setObjCKeywordID(ObjCID);
197}
198
199/// AddKeywords - Add all keywords to the symbol table.
200///
201void IdentifierTable::AddKeywords(const LangOptions &LangOpts) {
202  // Add keywords and tokens for the current language.
203#define KEYWORD(NAME, FLAGS) \
204  AddKeyword(StringRef(#NAME), tok::kw_ ## NAME,  \
205             FLAGS, LangOpts, *this);
206#define ALIAS(NAME, TOK, FLAGS) \
207  AddKeyword(StringRef(NAME), tok::kw_ ## TOK,  \
208             FLAGS, LangOpts, *this);
209#define CXX_KEYWORD_OPERATOR(NAME, ALIAS) \
210  if (LangOpts.CXXOperatorNames)          \
211    AddCXXOperatorKeyword(StringRef(#NAME), tok::ALIAS, *this);
212#define OBJC1_AT_KEYWORD(NAME) \
213  if (LangOpts.ObjC1)          \
214    AddObjCKeyword(StringRef(#NAME), tok::objc_##NAME, *this);
215#define OBJC2_AT_KEYWORD(NAME) \
216  if (LangOpts.ObjC2)          \
217    AddObjCKeyword(StringRef(#NAME), tok::objc_##NAME, *this);
218#define TESTING_KEYWORD(NAME, FLAGS)
219#include "clang/Basic/TokenKinds.def"
220
221  if (LangOpts.ParseUnknownAnytype)
222    AddKeyword("__unknown_anytype", tok::kw___unknown_anytype, KEYALL,
223               LangOpts, *this);
224
225  if (LangOpts.DeclSpecKeyword)
226    AddKeyword("__declspec", tok::kw___declspec, KEYALL, LangOpts, *this);
227}
228
229/// \brief Checks if the specified token kind represents a keyword in the
230/// specified language.
231/// \returns Status of the keyword in the language.
232static KeywordStatus getTokenKwStatus(const LangOptions &LangOpts,
233                                      tok::TokenKind K) {
234  switch (K) {
235#define KEYWORD(NAME, FLAGS) \
236  case tok::kw_##NAME: return getKeywordStatus(LangOpts, FLAGS);
237#include "clang/Basic/TokenKinds.def"
238  default: return KS_Disabled;
239  }
240}
241
242/// \brief Returns true if the identifier represents a keyword in the
243/// specified language.
244bool IdentifierInfo::isKeyword(const LangOptions &LangOpts) {
245  switch (getTokenKwStatus(LangOpts, getTokenID())) {
246  case KS_Enabled:
247  case KS_Extension:
248    return true;
249  default:
250    return false;
251  }
252}
253
254tok::PPKeywordKind IdentifierInfo::getPPKeywordID() const {
255  // We use a perfect hash function here involving the length of the keyword,
256  // the first and third character.  For preprocessor ID's there are no
257  // collisions (if there were, the switch below would complain about duplicate
258  // case values).  Note that this depends on 'if' being null terminated.
259
260#define HASH(LEN, FIRST, THIRD) \
261  (LEN << 5) + (((FIRST-'a') + (THIRD-'a')) & 31)
262#define CASE(LEN, FIRST, THIRD, NAME) \
263  case HASH(LEN, FIRST, THIRD): \
264    return memcmp(Name, #NAME, LEN) ? tok::pp_not_keyword : tok::pp_ ## NAME
265
266  unsigned Len = getLength();
267  if (Len < 2) return tok::pp_not_keyword;
268  const char *Name = getNameStart();
269  switch (HASH(Len, Name[0], Name[2])) {
270  default: return tok::pp_not_keyword;
271  CASE( 2, 'i', '\0', if);
272  CASE( 4, 'e', 'i', elif);
273  CASE( 4, 'e', 's', else);
274  CASE( 4, 'l', 'n', line);
275  CASE( 4, 's', 'c', sccs);
276  CASE( 5, 'e', 'd', endif);
277  CASE( 5, 'e', 'r', error);
278  CASE( 5, 'i', 'e', ident);
279  CASE( 5, 'i', 'd', ifdef);
280  CASE( 5, 'u', 'd', undef);
281
282  CASE( 6, 'a', 's', assert);
283  CASE( 6, 'd', 'f', define);
284  CASE( 6, 'i', 'n', ifndef);
285  CASE( 6, 'i', 'p', import);
286  CASE( 6, 'p', 'a', pragma);
287
288  CASE( 7, 'd', 'f', defined);
289  CASE( 7, 'i', 'c', include);
290  CASE( 7, 'w', 'r', warning);
291
292  CASE( 8, 'u', 'a', unassert);
293  CASE(12, 'i', 'c', include_next);
294
295  CASE(14, '_', 'p', __public_macro);
296
297  CASE(15, '_', 'p', __private_macro);
298
299  CASE(16, '_', 'i', __include_macros);
300#undef CASE
301#undef HASH
302  }
303}
304
305//===----------------------------------------------------------------------===//
306// Stats Implementation
307//===----------------------------------------------------------------------===//
308
309/// PrintStats - Print statistics about how well the identifier table is doing
310/// at hashing identifiers.
311void IdentifierTable::PrintStats() const {
312  unsigned NumBuckets = HashTable.getNumBuckets();
313  unsigned NumIdentifiers = HashTable.getNumItems();
314  unsigned NumEmptyBuckets = NumBuckets-NumIdentifiers;
315  unsigned AverageIdentifierSize = 0;
316  unsigned MaxIdentifierLength = 0;
317
318  // TODO: Figure out maximum times an identifier had to probe for -stats.
319  for (llvm::StringMap<IdentifierInfo*, llvm::BumpPtrAllocator>::const_iterator
320       I = HashTable.begin(), E = HashTable.end(); I != E; ++I) {
321    unsigned IdLen = I->getKeyLength();
322    AverageIdentifierSize += IdLen;
323    if (MaxIdentifierLength < IdLen)
324      MaxIdentifierLength = IdLen;
325  }
326
327  fprintf(stderr, "\n*** Identifier Table Stats:\n");
328  fprintf(stderr, "# Identifiers:   %d\n", NumIdentifiers);
329  fprintf(stderr, "# Empty Buckets: %d\n", NumEmptyBuckets);
330  fprintf(stderr, "Hash density (#identifiers per bucket): %f\n",
331          NumIdentifiers/(double)NumBuckets);
332  fprintf(stderr, "Ave identifier length: %f\n",
333          (AverageIdentifierSize/(double)NumIdentifiers));
334  fprintf(stderr, "Max identifier length: %d\n", MaxIdentifierLength);
335
336  // Compute statistics about the memory allocated for identifiers.
337  HashTable.getAllocator().PrintStats();
338}
339
340//===----------------------------------------------------------------------===//
341// SelectorTable Implementation
342//===----------------------------------------------------------------------===//
343
344unsigned llvm::DenseMapInfo<clang::Selector>::getHashValue(clang::Selector S) {
345  return DenseMapInfo<void*>::getHashValue(S.getAsOpaquePtr());
346}
347
348namespace clang {
349/// MultiKeywordSelector - One of these variable length records is kept for each
350/// selector containing more than one keyword. We use a folding set
351/// to unique aggregate names (keyword selectors in ObjC parlance). Access to
352/// this class is provided strictly through Selector.
353class MultiKeywordSelector
354  : public DeclarationNameExtra, public llvm::FoldingSetNode {
355  MultiKeywordSelector(unsigned nKeys) {
356    ExtraKindOrNumArgs = NUM_EXTRA_KINDS + nKeys;
357  }
358public:
359  // Constructor for keyword selectors.
360  MultiKeywordSelector(unsigned nKeys, IdentifierInfo **IIV) {
361    assert((nKeys > 1) && "not a multi-keyword selector");
362    ExtraKindOrNumArgs = NUM_EXTRA_KINDS + nKeys;
363
364    // Fill in the trailing keyword array.
365    IdentifierInfo **KeyInfo = reinterpret_cast<IdentifierInfo **>(this+1);
366    for (unsigned i = 0; i != nKeys; ++i)
367      KeyInfo[i] = IIV[i];
368  }
369
370  // getName - Derive the full selector name and return it.
371  std::string getName() const;
372
373  unsigned getNumArgs() const { return ExtraKindOrNumArgs - NUM_EXTRA_KINDS; }
374
375  typedef IdentifierInfo *const *keyword_iterator;
376  keyword_iterator keyword_begin() const {
377    return reinterpret_cast<keyword_iterator>(this+1);
378  }
379  keyword_iterator keyword_end() const {
380    return keyword_begin()+getNumArgs();
381  }
382  IdentifierInfo *getIdentifierInfoForSlot(unsigned i) const {
383    assert(i < getNumArgs() && "getIdentifierInfoForSlot(): illegal index");
384    return keyword_begin()[i];
385  }
386  static void Profile(llvm::FoldingSetNodeID &ID,
387                      keyword_iterator ArgTys, unsigned NumArgs) {
388    ID.AddInteger(NumArgs);
389    for (unsigned i = 0; i != NumArgs; ++i)
390      ID.AddPointer(ArgTys[i]);
391  }
392  void Profile(llvm::FoldingSetNodeID &ID) {
393    Profile(ID, keyword_begin(), getNumArgs());
394  }
395};
396} // end namespace clang.
397
398unsigned Selector::getNumArgs() const {
399  unsigned IIF = getIdentifierInfoFlag();
400  if (IIF <= ZeroArg)
401    return 0;
402  if (IIF == OneArg)
403    return 1;
404  // We point to a MultiKeywordSelector.
405  MultiKeywordSelector *SI = getMultiKeywordSelector();
406  return SI->getNumArgs();
407}
408
409IdentifierInfo *Selector::getIdentifierInfoForSlot(unsigned argIndex) const {
410  if (getIdentifierInfoFlag() < MultiArg) {
411    assert(argIndex == 0 && "illegal keyword index");
412    return getAsIdentifierInfo();
413  }
414  // We point to a MultiKeywordSelector.
415  MultiKeywordSelector *SI = getMultiKeywordSelector();
416  return SI->getIdentifierInfoForSlot(argIndex);
417}
418
419StringRef Selector::getNameForSlot(unsigned int argIndex) const {
420  IdentifierInfo *II = getIdentifierInfoForSlot(argIndex);
421  return II? II->getName() : StringRef();
422}
423
424std::string MultiKeywordSelector::getName() const {
425  SmallString<256> Str;
426  llvm::raw_svector_ostream OS(Str);
427  for (keyword_iterator I = keyword_begin(), E = keyword_end(); I != E; ++I) {
428    if (*I)
429      OS << (*I)->getName();
430    OS << ':';
431  }
432
433  return OS.str();
434}
435
436std::string Selector::getAsString() const {
437  if (InfoPtr == 0)
438    return "<null selector>";
439
440  if (getIdentifierInfoFlag() < MultiArg) {
441    IdentifierInfo *II = getAsIdentifierInfo();
442
443    // If the number of arguments is 0 then II is guaranteed to not be null.
444    if (getNumArgs() == 0)
445      return II->getName();
446
447    if (!II)
448      return ":";
449
450    return II->getName().str() + ":";
451  }
452
453  // We have a multiple keyword selector.
454  return getMultiKeywordSelector()->getName();
455}
456
457void Selector::print(llvm::raw_ostream &OS) const {
458  OS << getAsString();
459}
460
461/// Interpreting the given string using the normal CamelCase
462/// conventions, determine whether the given string starts with the
463/// given "word", which is assumed to end in a lowercase letter.
464static bool startsWithWord(StringRef name, StringRef word) {
465  if (name.size() < word.size()) return false;
466  return ((name.size() == word.size() || !isLowercase(name[word.size()])) &&
467          name.startswith(word));
468}
469
470ObjCMethodFamily Selector::getMethodFamilyImpl(Selector sel) {
471  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
472  if (!first) return OMF_None;
473
474  StringRef name = first->getName();
475  if (sel.isUnarySelector()) {
476    if (name == "autorelease") return OMF_autorelease;
477    if (name == "dealloc") return OMF_dealloc;
478    if (name == "finalize") return OMF_finalize;
479    if (name == "release") return OMF_release;
480    if (name == "retain") return OMF_retain;
481    if (name == "retainCount") return OMF_retainCount;
482    if (name == "self") return OMF_self;
483    if (name == "initialize") return OMF_initialize;
484  }
485
486  if (name == "performSelector") return OMF_performSelector;
487
488  // The other method families may begin with a prefix of underscores.
489  while (!name.empty() && name.front() == '_')
490    name = name.substr(1);
491
492  if (name.empty()) return OMF_None;
493  switch (name.front()) {
494  case 'a':
495    if (startsWithWord(name, "alloc")) return OMF_alloc;
496    break;
497  case 'c':
498    if (startsWithWord(name, "copy")) return OMF_copy;
499    break;
500  case 'i':
501    if (startsWithWord(name, "init")) return OMF_init;
502    break;
503  case 'm':
504    if (startsWithWord(name, "mutableCopy")) return OMF_mutableCopy;
505    break;
506  case 'n':
507    if (startsWithWord(name, "new")) return OMF_new;
508    break;
509  default:
510    break;
511  }
512
513  return OMF_None;
514}
515
516ObjCInstanceTypeFamily Selector::getInstTypeMethodFamily(Selector sel) {
517  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
518  if (!first) return OIT_None;
519
520  StringRef name = first->getName();
521
522  if (name.empty()) return OIT_None;
523  switch (name.front()) {
524    case 'a':
525      if (startsWithWord(name, "array")) return OIT_Array;
526      break;
527    case 'd':
528      if (startsWithWord(name, "default")) return OIT_ReturnsSelf;
529      if (startsWithWord(name, "dictionary")) return OIT_Dictionary;
530      break;
531    case 's':
532      if (startsWithWord(name, "shared")) return OIT_ReturnsSelf;
533      if (startsWithWord(name, "standard")) return OIT_Singleton;
534    case 'i':
535      if (startsWithWord(name, "init")) return OIT_Init;
536    default:
537      break;
538  }
539  return OIT_None;
540}
541
542ObjCStringFormatFamily Selector::getStringFormatFamilyImpl(Selector sel) {
543  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
544  if (!first) return SFF_None;
545
546  StringRef name = first->getName();
547
548  switch (name.front()) {
549    case 'a':
550      if (name == "appendFormat") return SFF_NSString;
551      break;
552
553    case 'i':
554      if (name == "initWithFormat") return SFF_NSString;
555      break;
556
557    case 'l':
558      if (name == "localizedStringWithFormat") return SFF_NSString;
559      break;
560
561    case 's':
562      if (name == "stringByAppendingFormat" ||
563          name == "stringWithFormat") return SFF_NSString;
564      break;
565  }
566  return SFF_None;
567}
568
569namespace {
570  struct SelectorTableImpl {
571    llvm::FoldingSet<MultiKeywordSelector> Table;
572    llvm::BumpPtrAllocator Allocator;
573  };
574} // end anonymous namespace.
575
576static SelectorTableImpl &getSelectorTableImpl(void *P) {
577  return *static_cast<SelectorTableImpl*>(P);
578}
579
580SmallString<64>
581SelectorTable::constructSetterName(StringRef Name) {
582  SmallString<64> SetterName("set");
583  SetterName += Name;
584  SetterName[3] = toUppercase(SetterName[3]);
585  return SetterName;
586}
587
588Selector
589SelectorTable::constructSetterSelector(IdentifierTable &Idents,
590                                       SelectorTable &SelTable,
591                                       const IdentifierInfo *Name) {
592  IdentifierInfo *SetterName =
593    &Idents.get(constructSetterName(Name->getName()));
594  return SelTable.getUnarySelector(SetterName);
595}
596
597size_t SelectorTable::getTotalMemory() const {
598  SelectorTableImpl &SelTabImpl = getSelectorTableImpl(Impl);
599  return SelTabImpl.Allocator.getTotalMemory();
600}
601
602Selector SelectorTable::getSelector(unsigned nKeys, IdentifierInfo **IIV) {
603  if (nKeys < 2)
604    return Selector(IIV[0], nKeys);
605
606  SelectorTableImpl &SelTabImpl = getSelectorTableImpl(Impl);
607
608  // Unique selector, to guarantee there is one per name.
609  llvm::FoldingSetNodeID ID;
610  MultiKeywordSelector::Profile(ID, IIV, nKeys);
611
612  void *InsertPos = nullptr;
613  if (MultiKeywordSelector *SI =
614        SelTabImpl.Table.FindNodeOrInsertPos(ID, InsertPos))
615    return Selector(SI);
616
617  // MultiKeywordSelector objects are not allocated with new because they have a
618  // variable size array (for parameter types) at the end of them.
619  unsigned Size = sizeof(MultiKeywordSelector) + nKeys*sizeof(IdentifierInfo *);
620  MultiKeywordSelector *SI =
621    (MultiKeywordSelector*)SelTabImpl.Allocator.Allocate(Size,
622                                         llvm::alignOf<MultiKeywordSelector>());
623  new (SI) MultiKeywordSelector(nKeys, IIV);
624  SelTabImpl.Table.InsertNode(SI, InsertPos);
625  return Selector(SI);
626}
627
628SelectorTable::SelectorTable() {
629  Impl = new SelectorTableImpl();
630}
631
632SelectorTable::~SelectorTable() {
633  delete &getSelectorTableImpl(Impl);
634}
635
636const char *clang::getOperatorSpelling(OverloadedOperatorKind Operator) {
637  switch (Operator) {
638  case OO_None:
639  case NUM_OVERLOADED_OPERATORS:
640    return nullptr;
641
642#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
643  case OO_##Name: return Spelling;
644#include "clang/Basic/OperatorKinds.def"
645  }
646
647  llvm_unreachable("Invalid OverloadedOperatorKind!");
648}
649
650StringRef clang::getNullabilitySpelling(NullabilityKind kind,
651                                        bool isContextSensitive) {
652  switch (kind) {
653  case NullabilityKind::NonNull:
654    return isContextSensitive ? "nonnull" : "_Nonnull";
655
656  case NullabilityKind::Nullable:
657    return isContextSensitive ? "nullable" : "_Nullable";
658
659  case NullabilityKind::Unspecified:
660    return isContextSensitive ? "null_unspecified" : "_Null_unspecified";
661  }
662  llvm_unreachable("Unknown nullability kind.");
663}
664