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 
27 using namespace clang;
28 
29 //===----------------------------------------------------------------------===//
30 // IdentifierInfo Implementation
31 //===----------------------------------------------------------------------===//
32 
IdentifierInfo()33 IdentifierInfo::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 
~IdentifierIterator()56 IdentifierIterator::~IdentifierIterator() { }
57 
~IdentifierInfoLookup()58 IdentifierInfoLookup::~IdentifierInfoLookup() {}
59 
60 namespace {
61   /// \brief A simple identifier lookup iterator that represents an
62   /// empty sequence of identifiers.
63   class EmptyLookupIterator : public IdentifierIterator
64   {
65   public:
Next()66     StringRef Next() override { return StringRef(); }
67   };
68 }
69 
getIdentifiers()70 IdentifierIterator *IdentifierInfoLookup::getIdentifiers() {
71   return new EmptyLookupIterator();
72 }
73 
IdentifierTable(const LangOptions & LangOpts,IdentifierInfoLookup * externalLookup)74 IdentifierTable::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
93 namespace {
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.
getKeywordStatus(const LangOptions & LangOpts,unsigned Flags)130 static 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.
AddKeyword(StringRef Keyword,tok::TokenKind TokenCode,unsigned Flags,const LangOptions & LangOpts,IdentifierTable & Table)159 static 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.
AddCXXOperatorKeyword(StringRef Keyword,tok::TokenKind TokenCode,IdentifierTable & Table)184 static 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".
AddObjCKeyword(StringRef Name,tok::ObjCKeywordKind ObjCID,IdentifierTable & Table)193 static 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 ///
AddKeywords(const LangOptions & LangOpts)201 void 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.
getTokenKwStatus(const LangOptions & LangOpts,tok::TokenKind K)232 static 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.
isKeyword(const LangOptions & LangOpts)244 bool 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 
getPPKeywordID() const254 tok::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.
PrintStats() const311 void 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 
getHashValue(clang::Selector S)344 unsigned llvm::DenseMapInfo<clang::Selector>::getHashValue(clang::Selector S) {
345   return DenseMapInfo<void*>::getHashValue(S.getAsOpaquePtr());
346 }
347 
348 namespace 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.
353 class MultiKeywordSelector
354   : public DeclarationNameExtra, public llvm::FoldingSetNode {
MultiKeywordSelector(unsigned nKeys)355   MultiKeywordSelector(unsigned nKeys) {
356     ExtraKindOrNumArgs = NUM_EXTRA_KINDS + nKeys;
357   }
358 public:
359   // Constructor for keyword selectors.
MultiKeywordSelector(unsigned nKeys,IdentifierInfo ** IIV)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 
getNumArgs() const373   unsigned getNumArgs() const { return ExtraKindOrNumArgs - NUM_EXTRA_KINDS; }
374 
375   typedef IdentifierInfo *const *keyword_iterator;
keyword_begin() const376   keyword_iterator keyword_begin() const {
377     return reinterpret_cast<keyword_iterator>(this+1);
378   }
keyword_end() const379   keyword_iterator keyword_end() const {
380     return keyword_begin()+getNumArgs();
381   }
getIdentifierInfoForSlot(unsigned i) const382   IdentifierInfo *getIdentifierInfoForSlot(unsigned i) const {
383     assert(i < getNumArgs() && "getIdentifierInfoForSlot(): illegal index");
384     return keyword_begin()[i];
385   }
Profile(llvm::FoldingSetNodeID & ID,keyword_iterator ArgTys,unsigned NumArgs)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   }
Profile(llvm::FoldingSetNodeID & ID)392   void Profile(llvm::FoldingSetNodeID &ID) {
393     Profile(ID, keyword_begin(), getNumArgs());
394   }
395 };
396 } // end namespace clang.
397 
getNumArgs() const398 unsigned 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 
getIdentifierInfoForSlot(unsigned argIndex) const409 IdentifierInfo *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 
getNameForSlot(unsigned int argIndex) const419 StringRef Selector::getNameForSlot(unsigned int argIndex) const {
420   IdentifierInfo *II = getIdentifierInfoForSlot(argIndex);
421   return II? II->getName() : StringRef();
422 }
423 
getName() const424 std::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 
getAsString() const436 std::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 
print(llvm::raw_ostream & OS) const457 void 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.
startsWithWord(StringRef name,StringRef word)464 static 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 
getMethodFamilyImpl(Selector sel)470 ObjCMethodFamily 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 
getInstTypeMethodFamily(Selector sel)516 ObjCInstanceTypeFamily 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 
getStringFormatFamilyImpl(Selector sel)542 ObjCStringFormatFamily 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 
569 namespace {
570   struct SelectorTableImpl {
571     llvm::FoldingSet<MultiKeywordSelector> Table;
572     llvm::BumpPtrAllocator Allocator;
573   };
574 } // end anonymous namespace.
575 
getSelectorTableImpl(void * P)576 static SelectorTableImpl &getSelectorTableImpl(void *P) {
577   return *static_cast<SelectorTableImpl*>(P);
578 }
579 
580 SmallString<64>
constructSetterName(StringRef Name)581 SelectorTable::constructSetterName(StringRef Name) {
582   SmallString<64> SetterName("set");
583   SetterName += Name;
584   SetterName[3] = toUppercase(SetterName[3]);
585   return SetterName;
586 }
587 
588 Selector
constructSetterSelector(IdentifierTable & Idents,SelectorTable & SelTable,const IdentifierInfo * Name)589 SelectorTable::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 
getTotalMemory() const597 size_t SelectorTable::getTotalMemory() const {
598   SelectorTableImpl &SelTabImpl = getSelectorTableImpl(Impl);
599   return SelTabImpl.Allocator.getTotalMemory();
600 }
601 
getSelector(unsigned nKeys,IdentifierInfo ** IIV)602 Selector 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 
SelectorTable()628 SelectorTable::SelectorTable() {
629   Impl = new SelectorTableImpl();
630 }
631 
~SelectorTable()632 SelectorTable::~SelectorTable() {
633   delete &getSelectorTableImpl(Impl);
634 }
635 
getOperatorSpelling(OverloadedOperatorKind Operator)636 const 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 
getNullabilitySpelling(NullabilityKind kind,bool isContextSensitive)650 StringRef 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