1//===- IdentifierTable.cpp - Hash table for identifier lookup -------------===//
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 implements the IdentifierInfo, IdentifierVisitor, and
10// IdentifierTable interfaces.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Basic/IdentifierTable.h"
15#include "clang/Basic/CharInfo.h"
16#include "clang/Basic/LangOptions.h"
17#include "clang/Basic/OperatorKinds.h"
18#include "clang/Basic/Specifiers.h"
19#include "clang/Basic/TargetBuiltins.h"
20#include "clang/Basic/TokenKinds.h"
21#include "llvm/ADT/DenseMapInfo.h"
22#include "llvm/ADT/FoldingSet.h"
23#include "llvm/ADT/SmallString.h"
24#include "llvm/ADT/StringMap.h"
25#include "llvm/ADT/StringRef.h"
26#include "llvm/Support/Allocator.h"
27#include "llvm/Support/ErrorHandling.h"
28#include "llvm/Support/raw_ostream.h"
29#include <cassert>
30#include <cstdio>
31#include <cstring>
32#include <string>
33
34using namespace clang;
35
36// A check to make sure the ObjCOrBuiltinID has sufficient room to store the
37// largest possible target/aux-target combination. If we exceed this, we likely
38// need to just change the ObjCOrBuiltinIDBits value in IdentifierTable.h.
39static_assert(2 * LargestBuiltinID < (2 << (ObjCOrBuiltinIDBits - 1)),
40              "Insufficient ObjCOrBuiltinID Bits");
41
42//===----------------------------------------------------------------------===//
43// IdentifierTable Implementation
44//===----------------------------------------------------------------------===//
45
46IdentifierIterator::~IdentifierIterator() = default;
47
48IdentifierInfoLookup::~IdentifierInfoLookup() = default;
49
50namespace {
51
52/// A simple identifier lookup iterator that represents an
53/// empty sequence of identifiers.
54class EmptyLookupIterator : public IdentifierIterator
55{
56public:
57  StringRef Next() override { return StringRef(); }
58};
59
60} // namespace
61
62IdentifierIterator *IdentifierInfoLookup::getIdentifiers() {
63  return new EmptyLookupIterator();
64}
65
66IdentifierTable::IdentifierTable(IdentifierInfoLookup *ExternalLookup)
67    : HashTable(8192), // Start with space for 8K identifiers.
68      ExternalLookup(ExternalLookup) {}
69
70IdentifierTable::IdentifierTable(const LangOptions &LangOpts,
71                                 IdentifierInfoLookup *ExternalLookup)
72    : IdentifierTable(ExternalLookup) {
73  // Populate the identifier table with info about keywords for the current
74  // language.
75  AddKeywords(LangOpts);
76}
77
78//===----------------------------------------------------------------------===//
79// Language Keyword Implementation
80//===----------------------------------------------------------------------===//
81
82// Constants for TokenKinds.def
83namespace {
84
85  enum {
86    KEYC99        = 0x1,
87    KEYCXX        = 0x2,
88    KEYCXX11      = 0x4,
89    KEYGNU        = 0x8,
90    KEYMS         = 0x10,
91    BOOLSUPPORT   = 0x20,
92    KEYALTIVEC    = 0x40,
93    KEYNOCXX      = 0x80,
94    KEYBORLAND    = 0x100,
95    KEYOPENCLC    = 0x200,
96    KEYC11        = 0x400,
97    KEYNOMS18     = 0x800,
98    KEYNOOPENCL   = 0x1000,
99    WCHARSUPPORT  = 0x2000,
100    HALFSUPPORT   = 0x4000,
101    CHAR8SUPPORT  = 0x8000,
102    KEYCONCEPTS   = 0x10000,
103    KEYOBJC       = 0x20000,
104    KEYZVECTOR    = 0x40000,
105    KEYCOROUTINES = 0x80000,
106    KEYMODULES    = 0x100000,
107    KEYCXX20      = 0x200000,
108    KEYOPENCLCXX  = 0x400000,
109    KEYMSCOMPAT   = 0x800000,
110    KEYALLCXX = KEYCXX | KEYCXX11 | KEYCXX20,
111    KEYALL = (0xffffff & ~KEYNOMS18 &
112              ~KEYNOOPENCL) // KEYNOMS18 and KEYNOOPENCL are used to exclude.
113  };
114
115  /// How a keyword is treated in the selected standard.
116  enum KeywordStatus {
117    KS_Disabled,    // Disabled
118    KS_Extension,   // Is an extension
119    KS_Enabled,     // Enabled
120    KS_Future       // Is a keyword in future standard
121  };
122
123} // namespace
124
125/// Translates flags as specified in TokenKinds.def into keyword status
126/// in the given language standard.
127static KeywordStatus getKeywordStatus(const LangOptions &LangOpts,
128                                      unsigned Flags) {
129  if (Flags == KEYALL) return KS_Enabled;
130  if (LangOpts.CPlusPlus && (Flags & KEYCXX)) return KS_Enabled;
131  if (LangOpts.CPlusPlus11 && (Flags & KEYCXX11)) return KS_Enabled;
132  if (LangOpts.CPlusPlus20 && (Flags & KEYCXX20)) return KS_Enabled;
133  if (LangOpts.C99 && (Flags & KEYC99)) return KS_Enabled;
134  if (LangOpts.GNUKeywords && (Flags & KEYGNU)) return KS_Extension;
135  if (LangOpts.MicrosoftExt && (Flags & KEYMS)) return KS_Extension;
136  if (LangOpts.MSVCCompat && (Flags & KEYMSCOMPAT)) return KS_Enabled;
137  if (LangOpts.Borland && (Flags & KEYBORLAND)) return KS_Extension;
138  if (LangOpts.Bool && (Flags & BOOLSUPPORT)) return KS_Enabled;
139  if (LangOpts.Half && (Flags & HALFSUPPORT)) return KS_Enabled;
140  if (LangOpts.WChar && (Flags & WCHARSUPPORT)) return KS_Enabled;
141  if (LangOpts.Char8 && (Flags & CHAR8SUPPORT)) return KS_Enabled;
142  if (LangOpts.AltiVec && (Flags & KEYALTIVEC)) return KS_Enabled;
143  if (LangOpts.ZVector && (Flags & KEYZVECTOR)) return KS_Enabled;
144  if (LangOpts.OpenCL && !LangOpts.OpenCLCPlusPlus && (Flags & KEYOPENCLC))
145    return KS_Enabled;
146  if (LangOpts.OpenCLCPlusPlus && (Flags & KEYOPENCLCXX)) return KS_Enabled;
147  if (!LangOpts.CPlusPlus && (Flags & KEYNOCXX)) return KS_Enabled;
148  if (LangOpts.C11 && (Flags & KEYC11)) return KS_Enabled;
149  // We treat bridge casts as objective-C keywords so we can warn on them
150  // in non-arc mode.
151  if (LangOpts.ObjC && (Flags & KEYOBJC)) return KS_Enabled;
152  if (LangOpts.CPlusPlus20 && (Flags & KEYCONCEPTS)) return KS_Enabled;
153  if (LangOpts.Coroutines && (Flags & KEYCOROUTINES)) return KS_Enabled;
154  if (LangOpts.ModulesTS && (Flags & KEYMODULES)) return KS_Enabled;
155  if (LangOpts.CPlusPlus && (Flags & KEYALLCXX)) return KS_Future;
156  if (LangOpts.CPlusPlus && !LangOpts.CPlusPlus20 && (Flags & CHAR8SUPPORT))
157    return KS_Future;
158  return KS_Disabled;
159}
160
161/// AddKeyword - This method is used to associate a token ID with specific
162/// identifiers because they are language keywords.  This causes the lexer to
163/// automatically map matching identifiers to specialized token codes.
164static void AddKeyword(StringRef Keyword,
165                       tok::TokenKind TokenCode, unsigned Flags,
166                       const LangOptions &LangOpts, IdentifierTable &Table) {
167  KeywordStatus AddResult = getKeywordStatus(LangOpts, Flags);
168
169  // Don't add this keyword under MSVCCompat.
170  if (LangOpts.MSVCCompat && (Flags & KEYNOMS18) &&
171      !LangOpts.isCompatibleWithMSVC(LangOptions::MSVC2015))
172    return;
173
174  // Don't add this keyword under OpenCL.
175  if (LangOpts.OpenCL && (Flags & KEYNOOPENCL))
176    return;
177
178  // Don't add this keyword if disabled in this language.
179  if (AddResult == KS_Disabled) return;
180
181  IdentifierInfo &Info =
182      Table.get(Keyword, AddResult == KS_Future ? tok::identifier : TokenCode);
183  Info.setIsExtensionToken(AddResult == KS_Extension);
184  Info.setIsFutureCompatKeyword(AddResult == KS_Future);
185}
186
187/// AddCXXOperatorKeyword - Register a C++ operator keyword alternative
188/// representations.
189static void AddCXXOperatorKeyword(StringRef Keyword,
190                                  tok::TokenKind TokenCode,
191                                  IdentifierTable &Table) {
192  IdentifierInfo &Info = Table.get(Keyword, TokenCode);
193  Info.setIsCPlusPlusOperatorKeyword();
194}
195
196/// AddObjCKeyword - Register an Objective-C \@keyword like "class" "selector"
197/// or "property".
198static void AddObjCKeyword(StringRef Name,
199                           tok::ObjCKeywordKind ObjCID,
200                           IdentifierTable &Table) {
201  Table.get(Name).setObjCKeywordID(ObjCID);
202}
203
204/// AddKeywords - Add all keywords to the symbol table.
205///
206void IdentifierTable::AddKeywords(const LangOptions &LangOpts) {
207  // Add keywords and tokens for the current language.
208#define KEYWORD(NAME, FLAGS) \
209  AddKeyword(StringRef(#NAME), tok::kw_ ## NAME,  \
210             FLAGS, LangOpts, *this);
211#define ALIAS(NAME, TOK, FLAGS) \
212  AddKeyword(StringRef(NAME), tok::kw_ ## TOK,  \
213             FLAGS, LangOpts, *this);
214#define CXX_KEYWORD_OPERATOR(NAME, ALIAS) \
215  if (LangOpts.CXXOperatorNames)          \
216    AddCXXOperatorKeyword(StringRef(#NAME), tok::ALIAS, *this);
217#define OBJC_AT_KEYWORD(NAME)  \
218  if (LangOpts.ObjC)           \
219    AddObjCKeyword(StringRef(#NAME), tok::objc_##NAME, *this);
220#define TESTING_KEYWORD(NAME, FLAGS)
221#include "clang/Basic/TokenKinds.def"
222
223  if (LangOpts.ParseUnknownAnytype)
224    AddKeyword("__unknown_anytype", tok::kw___unknown_anytype, KEYALL,
225               LangOpts, *this);
226
227  if (LangOpts.DeclSpecKeyword)
228    AddKeyword("__declspec", tok::kw___declspec, KEYALL, LangOpts, *this);
229
230  if (LangOpts.IEEE128)
231    AddKeyword("__ieee128", tok::kw___float128, KEYALL, LangOpts, *this);
232
233  // Add the 'import' contextual keyword.
234  get("import").setModulesImport(true);
235}
236
237/// Checks if the specified token kind represents a keyword in the
238/// specified language.
239/// \returns Status of the keyword in the language.
240static KeywordStatus getTokenKwStatus(const LangOptions &LangOpts,
241                                      tok::TokenKind K) {
242  switch (K) {
243#define KEYWORD(NAME, FLAGS) \
244  case tok::kw_##NAME: return getKeywordStatus(LangOpts, FLAGS);
245#include "clang/Basic/TokenKinds.def"
246  default: return KS_Disabled;
247  }
248}
249
250/// Returns true if the identifier represents a keyword in the
251/// specified language.
252bool IdentifierInfo::isKeyword(const LangOptions &LangOpts) const {
253  switch (getTokenKwStatus(LangOpts, getTokenID())) {
254  case KS_Enabled:
255  case KS_Extension:
256    return true;
257  default:
258    return false;
259  }
260}
261
262/// Returns true if the identifier represents a C++ keyword in the
263/// specified language.
264bool IdentifierInfo::isCPlusPlusKeyword(const LangOptions &LangOpts) const {
265  if (!LangOpts.CPlusPlus || !isKeyword(LangOpts))
266    return false;
267  // This is a C++ keyword if this identifier is not a keyword when checked
268  // using LangOptions without C++ support.
269  LangOptions LangOptsNoCPP = LangOpts;
270  LangOptsNoCPP.CPlusPlus = false;
271  LangOptsNoCPP.CPlusPlus11 = false;
272  LangOptsNoCPP.CPlusPlus20 = false;
273  return !isKeyword(LangOptsNoCPP);
274}
275
276ReservedIdentifierStatus
277IdentifierInfo::isReserved(const LangOptions &LangOpts) const {
278  StringRef Name = getName();
279
280  // '_' is a reserved identifier, but its use is so common (e.g. to store
281  // ignored values) that we don't warn on it.
282  if (Name.size() <= 1)
283    return ReservedIdentifierStatus::NotReserved;
284
285  // [lex.name] p3
286  if (Name[0] == '_') {
287
288    // Each name that begins with an underscore followed by an uppercase letter
289    // or another underscore is reserved.
290    if (Name[1] == '_')
291      return ReservedIdentifierStatus::StartsWithDoubleUnderscore;
292
293    if ('A' <= Name[1] && Name[1] <= 'Z')
294      return ReservedIdentifierStatus::
295          StartsWithUnderscoreFollowedByCapitalLetter;
296
297    // This is a bit misleading: it actually means it's only reserved if we're
298    // at global scope because it starts with an underscore.
299    return ReservedIdentifierStatus::StartsWithUnderscoreAtGlobalScope;
300  }
301
302  // Each name that contains a double underscore (__) is reserved.
303  if (LangOpts.CPlusPlus && Name.contains("__"))
304    return ReservedIdentifierStatus::ContainsDoubleUnderscore;
305
306  return ReservedIdentifierStatus::NotReserved;
307}
308
309tok::PPKeywordKind IdentifierInfo::getPPKeywordID() const {
310  // We use a perfect hash function here involving the length of the keyword,
311  // the first and third character.  For preprocessor ID's there are no
312  // collisions (if there were, the switch below would complain about duplicate
313  // case values).  Note that this depends on 'if' being null terminated.
314
315#define HASH(LEN, FIRST, THIRD) \
316  (LEN << 5) + (((FIRST-'a') + (THIRD-'a')) & 31)
317#define CASE(LEN, FIRST, THIRD, NAME) \
318  case HASH(LEN, FIRST, THIRD): \
319    return memcmp(Name, #NAME, LEN) ? tok::pp_not_keyword : tok::pp_ ## NAME
320
321  unsigned Len = getLength();
322  if (Len < 2) return tok::pp_not_keyword;
323  const char *Name = getNameStart();
324  switch (HASH(Len, Name[0], Name[2])) {
325  default: return tok::pp_not_keyword;
326  CASE( 2, 'i', '\0', if);
327  CASE( 4, 'e', 'i', elif);
328  CASE( 4, 'e', 's', else);
329  CASE( 4, 'l', 'n', line);
330  CASE( 4, 's', 'c', sccs);
331  CASE( 5, 'e', 'd', endif);
332  CASE( 5, 'e', 'r', error);
333  CASE( 5, 'i', 'e', ident);
334  CASE( 5, 'i', 'd', ifdef);
335  CASE( 5, 'u', 'd', undef);
336
337  CASE( 6, 'a', 's', assert);
338  CASE( 6, 'd', 'f', define);
339  CASE( 6, 'i', 'n', ifndef);
340  CASE( 6, 'i', 'p', import);
341  CASE( 6, 'p', 'a', pragma);
342
343  CASE( 7, 'd', 'f', defined);
344  CASE( 7, 'i', 'c', include);
345  CASE( 7, 'w', 'r', warning);
346
347  CASE( 8, 'u', 'a', unassert);
348  CASE(12, 'i', 'c', include_next);
349
350  CASE(14, '_', 'p', __public_macro);
351
352  CASE(15, '_', 'p', __private_macro);
353
354  CASE(16, '_', 'i', __include_macros);
355#undef CASE
356#undef HASH
357  }
358}
359
360//===----------------------------------------------------------------------===//
361// Stats Implementation
362//===----------------------------------------------------------------------===//
363
364/// PrintStats - Print statistics about how well the identifier table is doing
365/// at hashing identifiers.
366void IdentifierTable::PrintStats() const {
367  unsigned NumBuckets = HashTable.getNumBuckets();
368  unsigned NumIdentifiers = HashTable.getNumItems();
369  unsigned NumEmptyBuckets = NumBuckets-NumIdentifiers;
370  unsigned AverageIdentifierSize = 0;
371  unsigned MaxIdentifierLength = 0;
372
373  // TODO: Figure out maximum times an identifier had to probe for -stats.
374  for (llvm::StringMap<IdentifierInfo*, llvm::BumpPtrAllocator>::const_iterator
375       I = HashTable.begin(), E = HashTable.end(); I != E; ++I) {
376    unsigned IdLen = I->getKeyLength();
377    AverageIdentifierSize += IdLen;
378    if (MaxIdentifierLength < IdLen)
379      MaxIdentifierLength = IdLen;
380  }
381
382  fprintf(stderr, "\n*** Identifier Table Stats:\n");
383  fprintf(stderr, "# Identifiers:   %d\n", NumIdentifiers);
384  fprintf(stderr, "# Empty Buckets: %d\n", NumEmptyBuckets);
385  fprintf(stderr, "Hash density (#identifiers per bucket): %f\n",
386          NumIdentifiers/(double)NumBuckets);
387  fprintf(stderr, "Ave identifier length: %f\n",
388          (AverageIdentifierSize/(double)NumIdentifiers));
389  fprintf(stderr, "Max identifier length: %d\n", MaxIdentifierLength);
390
391  // Compute statistics about the memory allocated for identifiers.
392  HashTable.getAllocator().PrintStats();
393}
394
395//===----------------------------------------------------------------------===//
396// SelectorTable Implementation
397//===----------------------------------------------------------------------===//
398
399unsigned llvm::DenseMapInfo<clang::Selector>::getHashValue(clang::Selector S) {
400  return DenseMapInfo<void*>::getHashValue(S.getAsOpaquePtr());
401}
402
403namespace clang {
404
405/// One of these variable length records is kept for each
406/// selector containing more than one keyword. We use a folding set
407/// to unique aggregate names (keyword selectors in ObjC parlance). Access to
408/// this class is provided strictly through Selector.
409class alignas(IdentifierInfoAlignment) MultiKeywordSelector
410    : public detail::DeclarationNameExtra,
411      public llvm::FoldingSetNode {
412  MultiKeywordSelector(unsigned nKeys) : DeclarationNameExtra(nKeys) {}
413
414public:
415  // Constructor for keyword selectors.
416  MultiKeywordSelector(unsigned nKeys, IdentifierInfo **IIV)
417      : DeclarationNameExtra(nKeys) {
418    assert((nKeys > 1) && "not a multi-keyword selector");
419
420    // Fill in the trailing keyword array.
421    IdentifierInfo **KeyInfo = reinterpret_cast<IdentifierInfo **>(this + 1);
422    for (unsigned i = 0; i != nKeys; ++i)
423      KeyInfo[i] = IIV[i];
424  }
425
426  // getName - Derive the full selector name and return it.
427  std::string getName() const;
428
429  using DeclarationNameExtra::getNumArgs;
430
431  using keyword_iterator = IdentifierInfo *const *;
432
433  keyword_iterator keyword_begin() const {
434    return reinterpret_cast<keyword_iterator>(this + 1);
435  }
436
437  keyword_iterator keyword_end() const {
438    return keyword_begin() + getNumArgs();
439  }
440
441  IdentifierInfo *getIdentifierInfoForSlot(unsigned i) const {
442    assert(i < getNumArgs() && "getIdentifierInfoForSlot(): illegal index");
443    return keyword_begin()[i];
444  }
445
446  static void Profile(llvm::FoldingSetNodeID &ID, keyword_iterator ArgTys,
447                      unsigned NumArgs) {
448    ID.AddInteger(NumArgs);
449    for (unsigned i = 0; i != NumArgs; ++i)
450      ID.AddPointer(ArgTys[i]);
451  }
452
453  void Profile(llvm::FoldingSetNodeID &ID) {
454    Profile(ID, keyword_begin(), getNumArgs());
455  }
456};
457
458} // namespace clang.
459
460bool Selector::isKeywordSelector(ArrayRef<StringRef> Names) const {
461  assert(!Names.empty() && "must have >= 1 selector slots");
462  if (getNumArgs() != Names.size())
463    return false;
464  for (unsigned I = 0, E = Names.size(); I != E; ++I) {
465    if (getNameForSlot(I) != Names[I])
466      return false;
467  }
468  return true;
469}
470
471bool Selector::isUnarySelector(StringRef Name) const {
472  return isUnarySelector() && getNameForSlot(0) == Name;
473}
474
475unsigned Selector::getNumArgs() const {
476  unsigned IIF = getIdentifierInfoFlag();
477  if (IIF <= ZeroArg)
478    return 0;
479  if (IIF == OneArg)
480    return 1;
481  // We point to a MultiKeywordSelector.
482  MultiKeywordSelector *SI = getMultiKeywordSelector();
483  return SI->getNumArgs();
484}
485
486IdentifierInfo *Selector::getIdentifierInfoForSlot(unsigned argIndex) const {
487  if (getIdentifierInfoFlag() < MultiArg) {
488    assert(argIndex == 0 && "illegal keyword index");
489    return getAsIdentifierInfo();
490  }
491
492  // We point to a MultiKeywordSelector.
493  MultiKeywordSelector *SI = getMultiKeywordSelector();
494  return SI->getIdentifierInfoForSlot(argIndex);
495}
496
497StringRef Selector::getNameForSlot(unsigned int argIndex) const {
498  IdentifierInfo *II = getIdentifierInfoForSlot(argIndex);
499  return II ? II->getName() : StringRef();
500}
501
502std::string MultiKeywordSelector::getName() const {
503  SmallString<256> Str;
504  llvm::raw_svector_ostream OS(Str);
505  for (keyword_iterator I = keyword_begin(), E = keyword_end(); I != E; ++I) {
506    if (*I)
507      OS << (*I)->getName();
508    OS << ':';
509  }
510
511  return std::string(OS.str());
512}
513
514std::string Selector::getAsString() const {
515  if (InfoPtr == 0)
516    return "<null selector>";
517
518  if (getIdentifierInfoFlag() < MultiArg) {
519    IdentifierInfo *II = getAsIdentifierInfo();
520
521    if (getNumArgs() == 0) {
522      assert(II && "If the number of arguments is 0 then II is guaranteed to "
523                   "not be null.");
524      return std::string(II->getName());
525    }
526
527    if (!II)
528      return ":";
529
530    return II->getName().str() + ":";
531  }
532
533  // We have a multiple keyword selector.
534  return getMultiKeywordSelector()->getName();
535}
536
537void Selector::print(llvm::raw_ostream &OS) const {
538  OS << getAsString();
539}
540
541LLVM_DUMP_METHOD void Selector::dump() const { print(llvm::errs()); }
542
543/// Interpreting the given string using the normal CamelCase
544/// conventions, determine whether the given string starts with the
545/// given "word", which is assumed to end in a lowercase letter.
546static bool startsWithWord(StringRef name, StringRef word) {
547  if (name.size() < word.size()) return false;
548  return ((name.size() == word.size() || !isLowercase(name[word.size()])) &&
549          name.startswith(word));
550}
551
552ObjCMethodFamily Selector::getMethodFamilyImpl(Selector sel) {
553  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
554  if (!first) return OMF_None;
555
556  StringRef name = first->getName();
557  if (sel.isUnarySelector()) {
558    if (name == "autorelease") return OMF_autorelease;
559    if (name == "dealloc") return OMF_dealloc;
560    if (name == "finalize") return OMF_finalize;
561    if (name == "release") return OMF_release;
562    if (name == "retain") return OMF_retain;
563    if (name == "retainCount") return OMF_retainCount;
564    if (name == "self") return OMF_self;
565    if (name == "initialize") return OMF_initialize;
566  }
567
568  if (name == "performSelector" || name == "performSelectorInBackground" ||
569      name == "performSelectorOnMainThread")
570    return OMF_performSelector;
571
572  // The other method families may begin with a prefix of underscores.
573  while (!name.empty() && name.front() == '_')
574    name = name.substr(1);
575
576  if (name.empty()) return OMF_None;
577  switch (name.front()) {
578  case 'a':
579    if (startsWithWord(name, "alloc")) return OMF_alloc;
580    break;
581  case 'c':
582    if (startsWithWord(name, "copy")) return OMF_copy;
583    break;
584  case 'i':
585    if (startsWithWord(name, "init")) return OMF_init;
586    break;
587  case 'm':
588    if (startsWithWord(name, "mutableCopy")) return OMF_mutableCopy;
589    break;
590  case 'n':
591    if (startsWithWord(name, "new")) return OMF_new;
592    break;
593  default:
594    break;
595  }
596
597  return OMF_None;
598}
599
600ObjCInstanceTypeFamily Selector::getInstTypeMethodFamily(Selector sel) {
601  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
602  if (!first) return OIT_None;
603
604  StringRef name = first->getName();
605
606  if (name.empty()) return OIT_None;
607  switch (name.front()) {
608    case 'a':
609      if (startsWithWord(name, "array")) return OIT_Array;
610      break;
611    case 'd':
612      if (startsWithWord(name, "default")) return OIT_ReturnsSelf;
613      if (startsWithWord(name, "dictionary")) return OIT_Dictionary;
614      break;
615    case 's':
616      if (startsWithWord(name, "shared")) return OIT_ReturnsSelf;
617      if (startsWithWord(name, "standard")) return OIT_Singleton;
618      break;
619    case 'i':
620      if (startsWithWord(name, "init")) return OIT_Init;
621      break;
622    default:
623      break;
624  }
625  return OIT_None;
626}
627
628ObjCStringFormatFamily Selector::getStringFormatFamilyImpl(Selector sel) {
629  IdentifierInfo *first = sel.getIdentifierInfoForSlot(0);
630  if (!first) return SFF_None;
631
632  StringRef name = first->getName();
633
634  switch (name.front()) {
635    case 'a':
636      if (name == "appendFormat") return SFF_NSString;
637      break;
638
639    case 'i':
640      if (name == "initWithFormat") return SFF_NSString;
641      break;
642
643    case 'l':
644      if (name == "localizedStringWithFormat") return SFF_NSString;
645      break;
646
647    case 's':
648      if (name == "stringByAppendingFormat" ||
649          name == "stringWithFormat") return SFF_NSString;
650      break;
651  }
652  return SFF_None;
653}
654
655namespace {
656
657struct SelectorTableImpl {
658  llvm::FoldingSet<MultiKeywordSelector> Table;
659  llvm::BumpPtrAllocator Allocator;
660};
661
662} // namespace
663
664static SelectorTableImpl &getSelectorTableImpl(void *P) {
665  return *static_cast<SelectorTableImpl*>(P);
666}
667
668SmallString<64>
669SelectorTable::constructSetterName(StringRef Name) {
670  SmallString<64> SetterName("set");
671  SetterName += Name;
672  SetterName[3] = toUppercase(SetterName[3]);
673  return SetterName;
674}
675
676Selector
677SelectorTable::constructSetterSelector(IdentifierTable &Idents,
678                                       SelectorTable &SelTable,
679                                       const IdentifierInfo *Name) {
680  IdentifierInfo *SetterName =
681    &Idents.get(constructSetterName(Name->getName()));
682  return SelTable.getUnarySelector(SetterName);
683}
684
685std::string SelectorTable::getPropertyNameFromSetterSelector(Selector Sel) {
686  StringRef Name = Sel.getNameForSlot(0);
687  assert(Name.startswith("set") && "invalid setter name");
688  return (Twine(toLowercase(Name[3])) + Name.drop_front(4)).str();
689}
690
691size_t SelectorTable::getTotalMemory() const {
692  SelectorTableImpl &SelTabImpl = getSelectorTableImpl(Impl);
693  return SelTabImpl.Allocator.getTotalMemory();
694}
695
696Selector SelectorTable::getSelector(unsigned nKeys, IdentifierInfo **IIV) {
697  if (nKeys < 2)
698    return Selector(IIV[0], nKeys);
699
700  SelectorTableImpl &SelTabImpl = getSelectorTableImpl(Impl);
701
702  // Unique selector, to guarantee there is one per name.
703  llvm::FoldingSetNodeID ID;
704  MultiKeywordSelector::Profile(ID, IIV, nKeys);
705
706  void *InsertPos = nullptr;
707  if (MultiKeywordSelector *SI =
708        SelTabImpl.Table.FindNodeOrInsertPos(ID, InsertPos))
709    return Selector(SI);
710
711  // MultiKeywordSelector objects are not allocated with new because they have a
712  // variable size array (for parameter types) at the end of them.
713  unsigned Size = sizeof(MultiKeywordSelector) + nKeys*sizeof(IdentifierInfo *);
714  MultiKeywordSelector *SI =
715      (MultiKeywordSelector *)SelTabImpl.Allocator.Allocate(
716          Size, alignof(MultiKeywordSelector));
717  new (SI) MultiKeywordSelector(nKeys, IIV);
718  SelTabImpl.Table.InsertNode(SI, InsertPos);
719  return Selector(SI);
720}
721
722SelectorTable::SelectorTable() {
723  Impl = new SelectorTableImpl();
724}
725
726SelectorTable::~SelectorTable() {
727  delete &getSelectorTableImpl(Impl);
728}
729
730const char *clang::getOperatorSpelling(OverloadedOperatorKind Operator) {
731  switch (Operator) {
732  case OO_None:
733  case NUM_OVERLOADED_OPERATORS:
734    return nullptr;
735
736#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
737  case OO_##Name: return Spelling;
738#include "clang/Basic/OperatorKinds.def"
739  }
740
741  llvm_unreachable("Invalid OverloadedOperatorKind!");
742}
743
744StringRef clang::getNullabilitySpelling(NullabilityKind kind,
745                                        bool isContextSensitive) {
746  switch (kind) {
747  case NullabilityKind::NonNull:
748    return isContextSensitive ? "nonnull" : "_Nonnull";
749
750  case NullabilityKind::Nullable:
751    return isContextSensitive ? "nullable" : "_Nullable";
752
753  case NullabilityKind::NullableResult:
754    assert(!isContextSensitive &&
755           "_Nullable_result isn't supported as context-sensitive keyword");
756    return "_Nullable_result";
757
758  case NullabilityKind::Unspecified:
759    return isContextSensitive ? "null_unspecified" : "_Null_unspecified";
760  }
761  llvm_unreachable("Unknown nullability kind.");
762}
763