1 //===- DeclarationName.cpp - Declaration names implementation -------------===//
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 DeclarationName and DeclarationNameTable
10 // classes.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/DeclarationName.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclBase.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/AST/OpenMPClause.h"
21 #include "clang/AST/PrettyPrinter.h"
22 #include "clang/AST/Type.h"
23 #include "clang/AST/TypeLoc.h"
24 #include "clang/AST/TypeOrdering.h"
25 #include "clang/Basic/IdentifierTable.h"
26 #include "clang/Basic/LLVM.h"
27 #include "clang/Basic/LangOptions.h"
28 #include "clang/Basic/OperatorKinds.h"
29 #include "clang/Basic/SourceLocation.h"
30 #include "llvm/ADT/FoldingSet.h"
31 #include "llvm/Support/Casting.h"
32 #include "llvm/Support/Compiler.h"
33 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include <algorithm>
36 #include <cassert>
37 #include <cstdint>
38 #include <string>
39 
40 using namespace clang;
41 
42 static int compareInt(unsigned A, unsigned B) {
43   return (A < B ? -1 : (A > B ? 1 : 0));
44 }
45 
46 int DeclarationName::compare(DeclarationName LHS, DeclarationName RHS) {
47   if (LHS.getNameKind() != RHS.getNameKind())
48     return (LHS.getNameKind() < RHS.getNameKind() ? -1 : 1);
49 
50   switch (LHS.getNameKind()) {
51   case DeclarationName::Identifier: {
52     IdentifierInfo *LII = LHS.castAsIdentifierInfo();
53     IdentifierInfo *RII = RHS.castAsIdentifierInfo();
54     if (!LII)
55       return RII ? -1 : 0;
56     if (!RII)
57       return 1;
58 
59     return LII->getName().compare(RII->getName());
60   }
61 
62   case DeclarationName::ObjCZeroArgSelector:
63   case DeclarationName::ObjCOneArgSelector:
64   case DeclarationName::ObjCMultiArgSelector: {
65     Selector LHSSelector = LHS.getObjCSelector();
66     Selector RHSSelector = RHS.getObjCSelector();
67     // getNumArgs for ZeroArgSelector returns 0, but we still need to compare.
68     if (LHS.getNameKind() == DeclarationName::ObjCZeroArgSelector &&
69         RHS.getNameKind() == DeclarationName::ObjCZeroArgSelector) {
70       return LHSSelector.getAsIdentifierInfo()->getName().compare(
71           RHSSelector.getAsIdentifierInfo()->getName());
72     }
73     unsigned LN = LHSSelector.getNumArgs(), RN = RHSSelector.getNumArgs();
74     for (unsigned I = 0, N = std::min(LN, RN); I != N; ++I) {
75       if (int Compare = LHSSelector.getNameForSlot(I).compare(
76               RHSSelector.getNameForSlot(I)))
77         return Compare;
78     }
79 
80     return compareInt(LN, RN);
81   }
82 
83   case DeclarationName::CXXConstructorName:
84   case DeclarationName::CXXDestructorName:
85   case DeclarationName::CXXConversionFunctionName:
86     if (QualTypeOrdering()(LHS.getCXXNameType(), RHS.getCXXNameType()))
87       return -1;
88     if (QualTypeOrdering()(RHS.getCXXNameType(), LHS.getCXXNameType()))
89       return 1;
90     return 0;
91 
92   case DeclarationName::CXXDeductionGuideName:
93     // We never want to compare deduction guide names for templates from
94     // different scopes, so just compare the template-name.
95     return compare(LHS.getCXXDeductionGuideTemplate()->getDeclName(),
96                    RHS.getCXXDeductionGuideTemplate()->getDeclName());
97 
98   case DeclarationName::CXXOperatorName:
99     return compareInt(LHS.getCXXOverloadedOperator(),
100                       RHS.getCXXOverloadedOperator());
101 
102   case DeclarationName::CXXLiteralOperatorName:
103     return LHS.getCXXLiteralIdentifier()->getName().compare(
104         RHS.getCXXLiteralIdentifier()->getName());
105 
106   case DeclarationName::CXXUsingDirective:
107     return 0;
108   }
109 
110   llvm_unreachable("Invalid DeclarationName Kind!");
111 }
112 
113 static void printCXXConstructorDestructorName(QualType ClassType,
114                                               raw_ostream &OS,
115                                               PrintingPolicy Policy) {
116   // We know we're printing C++ here. Ensure we print types properly.
117   Policy.adjustForCPlusPlus();
118 
119   if (const RecordType *ClassRec = ClassType->getAs<RecordType>()) {
120     OS << *ClassRec->getDecl();
121     return;
122   }
123   if (Policy.SuppressTemplateArgsInCXXConstructors) {
124     if (auto *InjTy = ClassType->getAs<InjectedClassNameType>()) {
125       OS << *InjTy->getDecl();
126       return;
127     }
128   }
129   ClassType.print(OS, Policy);
130 }
131 
132 void DeclarationName::print(raw_ostream &OS,
133                             const PrintingPolicy &Policy) const {
134   switch (getNameKind()) {
135   case DeclarationName::Identifier:
136     if (const IdentifierInfo *II = getAsIdentifierInfo()) {
137       StringRef Name = II->getName();
138       // If this is a mangled OpenMP variant name we strip off the mangling for
139       // printing. It should not be visible to the user at all.
140       if (II->isMangledOpenMPVariantName()) {
141         std::pair<StringRef, StringRef> NameContextPair =
142             Name.split(getOpenMPVariantManglingSeparatorStr());
143         OS << NameContextPair.first << "["
144            << OMPTraitInfo(NameContextPair.second) << "]";
145       } else {
146         OS << Name;
147       }
148     }
149     return;
150 
151   case DeclarationName::ObjCZeroArgSelector:
152   case DeclarationName::ObjCOneArgSelector:
153   case DeclarationName::ObjCMultiArgSelector:
154     getObjCSelector().print(OS);
155     return;
156 
157   case DeclarationName::CXXConstructorName:
158     return printCXXConstructorDestructorName(getCXXNameType(), OS, Policy);
159 
160   case DeclarationName::CXXDestructorName:
161     OS << '~';
162     return printCXXConstructorDestructorName(getCXXNameType(), OS, Policy);
163 
164   case DeclarationName::CXXDeductionGuideName:
165     OS << "<deduction guide for ";
166     getCXXDeductionGuideTemplate()->getDeclName().print(OS, Policy);
167     OS << '>';
168     return;
169 
170   case DeclarationName::CXXOperatorName: {
171     const char *OpName = getOperatorSpelling(getCXXOverloadedOperator());
172     assert(OpName && "not an overloaded operator");
173 
174     OS << "operator";
175     if (OpName[0] >= 'a' && OpName[0] <= 'z')
176       OS << ' ';
177     OS << OpName;
178     return;
179   }
180 
181   case DeclarationName::CXXLiteralOperatorName:
182     OS << "operator\"\"" << getCXXLiteralIdentifier()->getName();
183     return;
184 
185   case DeclarationName::CXXConversionFunctionName: {
186     OS << "operator ";
187     QualType Type = getCXXNameType();
188     if (const RecordType *Rec = Type->getAs<RecordType>()) {
189       OS << *Rec->getDecl();
190       return;
191     }
192     // We know we're printing C++ here, ensure we print 'bool' properly.
193     PrintingPolicy CXXPolicy = Policy;
194     CXXPolicy.adjustForCPlusPlus();
195     Type.print(OS, CXXPolicy);
196     return;
197   }
198   case DeclarationName::CXXUsingDirective:
199     OS << "<using-directive>";
200     return;
201   }
202 
203   llvm_unreachable("Unexpected declaration name kind");
204 }
205 
206 namespace clang {
207 
208 raw_ostream &operator<<(raw_ostream &OS, DeclarationName N) {
209   LangOptions LO;
210   N.print(OS, PrintingPolicy(LO));
211   return OS;
212 }
213 
214 } // namespace clang
215 
216 bool DeclarationName::isDependentName() const {
217   QualType T = getCXXNameType();
218   if (!T.isNull() && T->isDependentType())
219     return true;
220 
221   // A class-scope deduction guide in a dependent context has a dependent name.
222   auto *TD = getCXXDeductionGuideTemplate();
223   if (TD && TD->getDeclContext()->isDependentContext())
224     return true;
225 
226   return false;
227 }
228 
229 std::string DeclarationName::getAsString() const {
230   std::string Result;
231   llvm::raw_string_ostream OS(Result);
232   OS << *this;
233   return Result;
234 }
235 
236 void *DeclarationName::getFETokenInfoSlow() const {
237   switch (getNameKind()) {
238   case Identifier:
239     llvm_unreachable("case Identifier already handled by getFETokenInfo!");
240   case CXXConstructorName:
241   case CXXDestructorName:
242   case CXXConversionFunctionName:
243     return castAsCXXSpecialNameExtra()->FETokenInfo;
244   case CXXOperatorName:
245     return castAsCXXOperatorIdName()->FETokenInfo;
246   case CXXDeductionGuideName:
247     return castAsCXXDeductionGuideNameExtra()->FETokenInfo;
248   case CXXLiteralOperatorName:
249     return castAsCXXLiteralOperatorIdName()->FETokenInfo;
250   default:
251     llvm_unreachable("DeclarationName has no FETokenInfo!");
252   }
253 }
254 
255 void DeclarationName::setFETokenInfoSlow(void *T) {
256   switch (getNameKind()) {
257   case Identifier:
258     llvm_unreachable("case Identifier already handled by setFETokenInfo!");
259   case CXXConstructorName:
260   case CXXDestructorName:
261   case CXXConversionFunctionName:
262     castAsCXXSpecialNameExtra()->FETokenInfo = T;
263     break;
264   case CXXOperatorName:
265     castAsCXXOperatorIdName()->FETokenInfo = T;
266     break;
267   case CXXDeductionGuideName:
268     castAsCXXDeductionGuideNameExtra()->FETokenInfo = T;
269     break;
270   case CXXLiteralOperatorName:
271     castAsCXXLiteralOperatorIdName()->FETokenInfo = T;
272     break;
273   default:
274     llvm_unreachable("DeclarationName has no FETokenInfo!");
275   }
276 }
277 
278 LLVM_DUMP_METHOD void DeclarationName::dump() const {
279   llvm::errs() << *this << '\n';
280 }
281 
282 DeclarationNameTable::DeclarationNameTable(const ASTContext &C) : Ctx(C) {
283   // Initialize the overloaded operator names.
284   for (unsigned Op = 0; Op < NUM_OVERLOADED_OPERATORS; ++Op)
285     CXXOperatorNames[Op].Kind = static_cast<OverloadedOperatorKind>(Op);
286 }
287 
288 DeclarationName
289 DeclarationNameTable::getCXXDeductionGuideName(TemplateDecl *Template) {
290   Template = cast<TemplateDecl>(Template->getCanonicalDecl());
291 
292   llvm::FoldingSetNodeID ID;
293   ID.AddPointer(Template);
294 
295   void *InsertPos = nullptr;
296   if (auto *Name = CXXDeductionGuideNames.FindNodeOrInsertPos(ID, InsertPos))
297     return DeclarationName(Name);
298 
299   auto *Name = new (Ctx) detail::CXXDeductionGuideNameExtra(Template);
300   CXXDeductionGuideNames.InsertNode(Name, InsertPos);
301   return DeclarationName(Name);
302 }
303 
304 DeclarationName DeclarationNameTable::getCXXConstructorName(CanQualType Ty) {
305   // The type of constructors is unqualified.
306   Ty = Ty.getUnqualifiedType();
307   // Do we already have this C++ constructor name ?
308   llvm::FoldingSetNodeID ID;
309   ID.AddPointer(Ty.getAsOpaquePtr());
310   void *InsertPos = nullptr;
311   if (auto *Name = CXXConstructorNames.FindNodeOrInsertPos(ID, InsertPos))
312     return {Name, DeclarationName::StoredCXXConstructorName};
313 
314   // We have to create it.
315   auto *SpecialName = new (Ctx) detail::CXXSpecialNameExtra(Ty);
316   CXXConstructorNames.InsertNode(SpecialName, InsertPos);
317   return {SpecialName, DeclarationName::StoredCXXConstructorName};
318 }
319 
320 DeclarationName DeclarationNameTable::getCXXDestructorName(CanQualType Ty) {
321   // The type of destructors is unqualified.
322   Ty = Ty.getUnqualifiedType();
323   // Do we already have this C++ destructor name ?
324   llvm::FoldingSetNodeID ID;
325   ID.AddPointer(Ty.getAsOpaquePtr());
326   void *InsertPos = nullptr;
327   if (auto *Name = CXXDestructorNames.FindNodeOrInsertPos(ID, InsertPos))
328     return {Name, DeclarationName::StoredCXXDestructorName};
329 
330   // We have to create it.
331   auto *SpecialName = new (Ctx) detail::CXXSpecialNameExtra(Ty);
332   CXXDestructorNames.InsertNode(SpecialName, InsertPos);
333   return {SpecialName, DeclarationName::StoredCXXDestructorName};
334 }
335 
336 DeclarationName
337 DeclarationNameTable::getCXXConversionFunctionName(CanQualType Ty) {
338   // Do we already have this C++ conversion function name ?
339   llvm::FoldingSetNodeID ID;
340   ID.AddPointer(Ty.getAsOpaquePtr());
341   void *InsertPos = nullptr;
342   if (auto *Name =
343           CXXConversionFunctionNames.FindNodeOrInsertPos(ID, InsertPos))
344     return {Name, DeclarationName::StoredCXXConversionFunctionName};
345 
346   // We have to create it.
347   auto *SpecialName = new (Ctx) detail::CXXSpecialNameExtra(Ty);
348   CXXConversionFunctionNames.InsertNode(SpecialName, InsertPos);
349   return {SpecialName, DeclarationName::StoredCXXConversionFunctionName};
350 }
351 
352 DeclarationName
353 DeclarationNameTable::getCXXSpecialName(DeclarationName::NameKind Kind,
354                                         CanQualType Ty) {
355   switch (Kind) {
356   case DeclarationName::CXXConstructorName:
357     return getCXXConstructorName(Ty);
358   case DeclarationName::CXXDestructorName:
359     return getCXXDestructorName(Ty);
360   case DeclarationName::CXXConversionFunctionName:
361     return getCXXConversionFunctionName(Ty);
362   default:
363     llvm_unreachable("Invalid kind in getCXXSpecialName!");
364   }
365 }
366 
367 DeclarationName
368 DeclarationNameTable::getCXXLiteralOperatorName(IdentifierInfo *II) {
369   llvm::FoldingSetNodeID ID;
370   ID.AddPointer(II);
371 
372   void *InsertPos = nullptr;
373   if (auto *Name = CXXLiteralOperatorNames.FindNodeOrInsertPos(ID, InsertPos))
374     return DeclarationName(Name);
375 
376   auto *LiteralName = new (Ctx) detail::CXXLiteralOperatorIdName(II);
377   CXXLiteralOperatorNames.InsertNode(LiteralName, InsertPos);
378   return DeclarationName(LiteralName);
379 }
380 
381 DeclarationNameLoc::DeclarationNameLoc(DeclarationName Name) {
382   switch (Name.getNameKind()) {
383   case DeclarationName::Identifier:
384   case DeclarationName::CXXDeductionGuideName:
385     break;
386   case DeclarationName::CXXConstructorName:
387   case DeclarationName::CXXDestructorName:
388   case DeclarationName::CXXConversionFunctionName:
389     setNamedTypeLoc(nullptr);
390     break;
391   case DeclarationName::CXXOperatorName:
392     setCXXOperatorNameRange(SourceRange());
393     break;
394   case DeclarationName::CXXLiteralOperatorName:
395     setCXXLiteralOperatorNameLoc(SourceLocation());
396     break;
397   case DeclarationName::ObjCZeroArgSelector:
398   case DeclarationName::ObjCOneArgSelector:
399   case DeclarationName::ObjCMultiArgSelector:
400     // FIXME: ?
401     break;
402   case DeclarationName::CXXUsingDirective:
403     break;
404   }
405 }
406 
407 bool DeclarationNameInfo::containsUnexpandedParameterPack() const {
408   switch (Name.getNameKind()) {
409   case DeclarationName::Identifier:
410   case DeclarationName::ObjCZeroArgSelector:
411   case DeclarationName::ObjCOneArgSelector:
412   case DeclarationName::ObjCMultiArgSelector:
413   case DeclarationName::CXXOperatorName:
414   case DeclarationName::CXXLiteralOperatorName:
415   case DeclarationName::CXXUsingDirective:
416   case DeclarationName::CXXDeductionGuideName:
417     return false;
418 
419   case DeclarationName::CXXConstructorName:
420   case DeclarationName::CXXDestructorName:
421   case DeclarationName::CXXConversionFunctionName:
422     if (TypeSourceInfo *TInfo = LocInfo.getNamedTypeInfo())
423       return TInfo->getType()->containsUnexpandedParameterPack();
424 
425     return Name.getCXXNameType()->containsUnexpandedParameterPack();
426   }
427   llvm_unreachable("All name kinds handled.");
428 }
429 
430 bool DeclarationNameInfo::isInstantiationDependent() const {
431   switch (Name.getNameKind()) {
432   case DeclarationName::Identifier:
433   case DeclarationName::ObjCZeroArgSelector:
434   case DeclarationName::ObjCOneArgSelector:
435   case DeclarationName::ObjCMultiArgSelector:
436   case DeclarationName::CXXOperatorName:
437   case DeclarationName::CXXLiteralOperatorName:
438   case DeclarationName::CXXUsingDirective:
439   case DeclarationName::CXXDeductionGuideName:
440     return false;
441 
442   case DeclarationName::CXXConstructorName:
443   case DeclarationName::CXXDestructorName:
444   case DeclarationName::CXXConversionFunctionName:
445     if (TypeSourceInfo *TInfo = LocInfo.getNamedTypeInfo())
446       return TInfo->getType()->isInstantiationDependentType();
447 
448     return Name.getCXXNameType()->isInstantiationDependentType();
449   }
450   llvm_unreachable("All name kinds handled.");
451 }
452 
453 std::string DeclarationNameInfo::getAsString() const {
454   std::string Result;
455   llvm::raw_string_ostream OS(Result);
456   OS << *this;
457   return Result;
458 }
459 
460 raw_ostream &clang::operator<<(raw_ostream &OS, DeclarationNameInfo DNInfo) {
461   LangOptions LO;
462   DNInfo.printName(OS, PrintingPolicy(LangOptions()));
463   return OS;
464 }
465 
466 void DeclarationNameInfo::printName(raw_ostream &OS, PrintingPolicy Policy) const {
467   switch (Name.getNameKind()) {
468   case DeclarationName::Identifier:
469   case DeclarationName::ObjCZeroArgSelector:
470   case DeclarationName::ObjCOneArgSelector:
471   case DeclarationName::ObjCMultiArgSelector:
472   case DeclarationName::CXXOperatorName:
473   case DeclarationName::CXXLiteralOperatorName:
474   case DeclarationName::CXXUsingDirective:
475   case DeclarationName::CXXDeductionGuideName:
476     Name.print(OS, Policy);
477     return;
478 
479   case DeclarationName::CXXConstructorName:
480   case DeclarationName::CXXDestructorName:
481   case DeclarationName::CXXConversionFunctionName:
482     if (TypeSourceInfo *TInfo = LocInfo.getNamedTypeInfo()) {
483       if (Name.getNameKind() == DeclarationName::CXXDestructorName)
484         OS << '~';
485       else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName)
486         OS << "operator ";
487       LangOptions LO;
488       Policy.adjustForCPlusPlus();
489       Policy.SuppressScope = true;
490       OS << TInfo->getType().getAsString(Policy);
491     } else
492       Name.print(OS, Policy);
493     return;
494   }
495   llvm_unreachable("Unexpected declaration name kind");
496 }
497 
498 SourceLocation DeclarationNameInfo::getEndLocPrivate() const {
499   switch (Name.getNameKind()) {
500   case DeclarationName::Identifier:
501   case DeclarationName::CXXDeductionGuideName:
502     return NameLoc;
503 
504   case DeclarationName::CXXOperatorName:
505     return LocInfo.getCXXOperatorNameEndLoc();
506 
507   case DeclarationName::CXXLiteralOperatorName:
508     return LocInfo.getCXXLiteralOperatorNameLoc();
509 
510   case DeclarationName::CXXConstructorName:
511   case DeclarationName::CXXDestructorName:
512   case DeclarationName::CXXConversionFunctionName:
513     if (TypeSourceInfo *TInfo = LocInfo.getNamedTypeInfo())
514       return TInfo->getTypeLoc().getEndLoc();
515     else
516       return NameLoc;
517 
518     // DNInfo work in progress: FIXME.
519   case DeclarationName::ObjCZeroArgSelector:
520   case DeclarationName::ObjCOneArgSelector:
521   case DeclarationName::ObjCMultiArgSelector:
522   case DeclarationName::CXXUsingDirective:
523     return NameLoc;
524   }
525   llvm_unreachable("Unexpected declaration name kind");
526 }
527