1 //===------- QualTypeNames.cpp - Generate Complete QualType Names ---------===//
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 #include "clang/AST/DeclTemplate.h"
10 #include "clang/AST/DeclarationName.h"
11 #include "clang/AST/GlobalDecl.h"
12 #include "clang/AST/Mangle.h"
13 #include "clang/AST/QualTypeNames.h"
14
15 #include <stdio.h>
16 #include <memory>
17
18 namespace clang {
19
20 namespace TypeName {
21
22 /// Create a NestedNameSpecifier for Namesp and its enclosing
23 /// scopes.
24 ///
25 /// \param[in] Ctx - the AST Context to be used.
26 /// \param[in] Namesp - the NamespaceDecl for which a NestedNameSpecifier
27 /// is requested.
28 /// \param[in] WithGlobalNsPrefix - Indicate whether the global namespace
29 /// specifier "::" should be prepended or not.
30 static NestedNameSpecifier *createNestedNameSpecifier(
31 const ASTContext &Ctx,
32 const NamespaceDecl *Namesp,
33 bool WithGlobalNsPrefix);
34
35 /// Create a NestedNameSpecifier for TagDecl and its enclosing
36 /// scopes.
37 ///
38 /// \param[in] Ctx - the AST Context to be used.
39 /// \param[in] TD - the TagDecl for which a NestedNameSpecifier is
40 /// requested.
41 /// \param[in] FullyQualify - Convert all template arguments into fully
42 /// qualified names.
43 /// \param[in] WithGlobalNsPrefix - Indicate whether the global namespace
44 /// specifier "::" should be prepended or not.
45 static NestedNameSpecifier *createNestedNameSpecifier(
46 const ASTContext &Ctx, const TypeDecl *TD,
47 bool FullyQualify, bool WithGlobalNsPrefix);
48
49 static NestedNameSpecifier *createNestedNameSpecifierForScopeOf(
50 const ASTContext &Ctx, const Decl *decl,
51 bool FullyQualified, bool WithGlobalNsPrefix);
52
53 static NestedNameSpecifier *getFullyQualifiedNestedNameSpecifier(
54 const ASTContext &Ctx, NestedNameSpecifier *scope, bool WithGlobalNsPrefix);
55
getFullyQualifiedTemplateName(const ASTContext & Ctx,TemplateName & TName,bool WithGlobalNsPrefix)56 static bool getFullyQualifiedTemplateName(const ASTContext &Ctx,
57 TemplateName &TName,
58 bool WithGlobalNsPrefix) {
59 bool Changed = false;
60 NestedNameSpecifier *NNS = nullptr;
61
62 TemplateDecl *ArgTDecl = TName.getAsTemplateDecl();
63 // ArgTDecl won't be NULL because we asserted that this isn't a
64 // dependent context very early in the call chain.
65 assert(ArgTDecl != nullptr);
66 QualifiedTemplateName *QTName = TName.getAsQualifiedTemplateName();
67
68 if (QTName && !QTName->hasTemplateKeyword()) {
69 NNS = QTName->getQualifier();
70 NestedNameSpecifier *QNNS = getFullyQualifiedNestedNameSpecifier(
71 Ctx, NNS, WithGlobalNsPrefix);
72 if (QNNS != NNS) {
73 Changed = true;
74 NNS = QNNS;
75 } else {
76 NNS = nullptr;
77 }
78 } else {
79 NNS = createNestedNameSpecifierForScopeOf(
80 Ctx, ArgTDecl, true, WithGlobalNsPrefix);
81 }
82 if (NNS) {
83 TName = Ctx.getQualifiedTemplateName(NNS,
84 /*TemplateKeyword=*/false, ArgTDecl);
85 Changed = true;
86 }
87 return Changed;
88 }
89
getFullyQualifiedTemplateArgument(const ASTContext & Ctx,TemplateArgument & Arg,bool WithGlobalNsPrefix)90 static bool getFullyQualifiedTemplateArgument(const ASTContext &Ctx,
91 TemplateArgument &Arg,
92 bool WithGlobalNsPrefix) {
93 bool Changed = false;
94
95 // Note: we do not handle TemplateArgument::Expression, to replace it
96 // we need the information for the template instance decl.
97
98 if (Arg.getKind() == TemplateArgument::Template) {
99 TemplateName TName = Arg.getAsTemplate();
100 Changed = getFullyQualifiedTemplateName(Ctx, TName, WithGlobalNsPrefix);
101 if (Changed) {
102 Arg = TemplateArgument(TName);
103 }
104 } else if (Arg.getKind() == TemplateArgument::Type) {
105 QualType SubTy = Arg.getAsType();
106 // Check if the type needs more desugaring and recurse.
107 QualType QTFQ = getFullyQualifiedType(SubTy, Ctx, WithGlobalNsPrefix);
108 if (QTFQ != SubTy) {
109 Arg = TemplateArgument(QTFQ);
110 Changed = true;
111 }
112 }
113 return Changed;
114 }
115
getFullyQualifiedTemplateType(const ASTContext & Ctx,const Type * TypePtr,bool WithGlobalNsPrefix)116 static const Type *getFullyQualifiedTemplateType(const ASTContext &Ctx,
117 const Type *TypePtr,
118 bool WithGlobalNsPrefix) {
119 // DependentTemplateTypes exist within template declarations and
120 // definitions. Therefore we shouldn't encounter them at the end of
121 // a translation unit. If we do, the caller has made an error.
122 assert(!isa<DependentTemplateSpecializationType>(TypePtr));
123 // In case of template specializations, iterate over the arguments
124 // and fully qualify them as well.
125 if (const auto *TST = dyn_cast<const TemplateSpecializationType>(TypePtr)) {
126 bool MightHaveChanged = false;
127 SmallVector<TemplateArgument, 4> FQArgs;
128 for (TemplateSpecializationType::iterator I = TST->begin(), E = TST->end();
129 I != E; ++I) {
130 // Cheap to copy and potentially modified by
131 // getFullyQualifedTemplateArgument.
132 TemplateArgument Arg(*I);
133 MightHaveChanged |= getFullyQualifiedTemplateArgument(
134 Ctx, Arg, WithGlobalNsPrefix);
135 FQArgs.push_back(Arg);
136 }
137
138 // If a fully qualified arg is different from the unqualified arg,
139 // allocate new type in the AST.
140 if (MightHaveChanged) {
141 QualType QT = Ctx.getTemplateSpecializationType(
142 TST->getTemplateName(), FQArgs,
143 TST->getCanonicalTypeInternal());
144 // getTemplateSpecializationType returns a fully qualified
145 // version of the specialization itself, so no need to qualify
146 // it.
147 return QT.getTypePtr();
148 }
149 } else if (const auto *TSTRecord = dyn_cast<const RecordType>(TypePtr)) {
150 // We are asked to fully qualify and we have a Record Type,
151 // which can point to a template instantiation with no sugar in any of
152 // its template argument, however we still need to fully qualify them.
153
154 if (const auto *TSTDecl =
155 dyn_cast<ClassTemplateSpecializationDecl>(TSTRecord->getDecl())) {
156 const TemplateArgumentList &TemplateArgs = TSTDecl->getTemplateArgs();
157
158 bool MightHaveChanged = false;
159 SmallVector<TemplateArgument, 4> FQArgs;
160 for (unsigned int I = 0, E = TemplateArgs.size(); I != E; ++I) {
161 // cheap to copy and potentially modified by
162 // getFullyQualifedTemplateArgument
163 TemplateArgument Arg(TemplateArgs[I]);
164 MightHaveChanged |= getFullyQualifiedTemplateArgument(
165 Ctx, Arg, WithGlobalNsPrefix);
166 FQArgs.push_back(Arg);
167 }
168
169 // If a fully qualified arg is different from the unqualified arg,
170 // allocate new type in the AST.
171 if (MightHaveChanged) {
172 TemplateName TN(TSTDecl->getSpecializedTemplate());
173 QualType QT = Ctx.getTemplateSpecializationType(
174 TN, FQArgs,
175 TSTRecord->getCanonicalTypeInternal());
176 // getTemplateSpecializationType returns a fully qualified
177 // version of the specialization itself, so no need to qualify
178 // it.
179 return QT.getTypePtr();
180 }
181 }
182 }
183 return TypePtr;
184 }
185
createOuterNNS(const ASTContext & Ctx,const Decl * D,bool FullyQualify,bool WithGlobalNsPrefix)186 static NestedNameSpecifier *createOuterNNS(const ASTContext &Ctx, const Decl *D,
187 bool FullyQualify,
188 bool WithGlobalNsPrefix) {
189 const DeclContext *DC = D->getDeclContext();
190 if (const auto *NS = dyn_cast<NamespaceDecl>(DC)) {
191 while (NS && NS->isInline()) {
192 // Ignore inline namespace;
193 NS = dyn_cast<NamespaceDecl>(NS->getDeclContext());
194 }
195 if (NS && NS->getDeclName()) {
196 return createNestedNameSpecifier(Ctx, NS, WithGlobalNsPrefix);
197 }
198 return nullptr; // no starting '::', no anonymous
199 } else if (const auto *TD = dyn_cast<TagDecl>(DC)) {
200 return createNestedNameSpecifier(Ctx, TD, FullyQualify, WithGlobalNsPrefix);
201 } else if (const auto *TDD = dyn_cast<TypedefNameDecl>(DC)) {
202 return createNestedNameSpecifier(
203 Ctx, TDD, FullyQualify, WithGlobalNsPrefix);
204 } else if (WithGlobalNsPrefix && DC->isTranslationUnit()) {
205 return NestedNameSpecifier::GlobalSpecifier(Ctx);
206 }
207 return nullptr; // no starting '::' if |WithGlobalNsPrefix| is false
208 }
209
210 /// Return a fully qualified version of this name specifier.
getFullyQualifiedNestedNameSpecifier(const ASTContext & Ctx,NestedNameSpecifier * Scope,bool WithGlobalNsPrefix)211 static NestedNameSpecifier *getFullyQualifiedNestedNameSpecifier(
212 const ASTContext &Ctx, NestedNameSpecifier *Scope,
213 bool WithGlobalNsPrefix) {
214 switch (Scope->getKind()) {
215 case NestedNameSpecifier::Global:
216 // Already fully qualified
217 return Scope;
218 case NestedNameSpecifier::Namespace:
219 return TypeName::createNestedNameSpecifier(
220 Ctx, Scope->getAsNamespace(), WithGlobalNsPrefix);
221 case NestedNameSpecifier::NamespaceAlias:
222 // Namespace aliases are only valid for the duration of the
223 // scope where they were introduced, and therefore are often
224 // invalid at the end of the TU. So use the namespace name more
225 // likely to be valid at the end of the TU.
226 return TypeName::createNestedNameSpecifier(
227 Ctx,
228 Scope->getAsNamespaceAlias()->getNamespace()->getCanonicalDecl(),
229 WithGlobalNsPrefix);
230 case NestedNameSpecifier::Identifier:
231 // A function or some other construct that makes it un-namable
232 // at the end of the TU. Skip the current component of the name,
233 // but use the name of it's prefix.
234 return getFullyQualifiedNestedNameSpecifier(
235 Ctx, Scope->getPrefix(), WithGlobalNsPrefix);
236 case NestedNameSpecifier::Super:
237 case NestedNameSpecifier::TypeSpec:
238 case NestedNameSpecifier::TypeSpecWithTemplate: {
239 const Type *Type = Scope->getAsType();
240 // Find decl context.
241 const TagDecl *TD = nullptr;
242 if (const TagType *TagDeclType = Type->getAs<TagType>()) {
243 TD = TagDeclType->getDecl();
244 } else {
245 TD = Type->getAsCXXRecordDecl();
246 }
247 if (TD) {
248 return TypeName::createNestedNameSpecifier(Ctx, TD,
249 true /*FullyQualified*/,
250 WithGlobalNsPrefix);
251 } else if (const auto *TDD = dyn_cast<TypedefType>(Type)) {
252 return TypeName::createNestedNameSpecifier(Ctx, TDD->getDecl(),
253 true /*FullyQualified*/,
254 WithGlobalNsPrefix);
255 }
256 return Scope;
257 }
258 }
259 llvm_unreachable("bad NNS kind");
260 }
261
262 /// Create a nested name specifier for the declaring context of
263 /// the type.
createNestedNameSpecifierForScopeOf(const ASTContext & Ctx,const Decl * Decl,bool FullyQualified,bool WithGlobalNsPrefix)264 static NestedNameSpecifier *createNestedNameSpecifierForScopeOf(
265 const ASTContext &Ctx, const Decl *Decl,
266 bool FullyQualified, bool WithGlobalNsPrefix) {
267 assert(Decl);
268
269 const DeclContext *DC = Decl->getDeclContext()->getRedeclContext();
270 const auto *Outer = dyn_cast_or_null<NamedDecl>(DC);
271 const auto *OuterNS = dyn_cast_or_null<NamespaceDecl>(DC);
272 if (Outer && !(OuterNS && OuterNS->isAnonymousNamespace())) {
273 if (const auto *CxxDecl = dyn_cast<CXXRecordDecl>(DC)) {
274 if (ClassTemplateDecl *ClassTempl =
275 CxxDecl->getDescribedClassTemplate()) {
276 // We are in the case of a type(def) that was declared in a
277 // class template but is *not* type dependent. In clang, it
278 // gets attached to the class template declaration rather than
279 // any specific class template instantiation. This result in
280 // 'odd' fully qualified typename:
281 //
282 // vector<_Tp,_Alloc>::size_type
283 //
284 // Make the situation is 'useable' but looking a bit odd by
285 // picking a random instance as the declaring context.
286 if (ClassTempl->spec_begin() != ClassTempl->spec_end()) {
287 Decl = *(ClassTempl->spec_begin());
288 Outer = dyn_cast<NamedDecl>(Decl);
289 OuterNS = dyn_cast<NamespaceDecl>(Decl);
290 }
291 }
292 }
293
294 if (OuterNS) {
295 return createNestedNameSpecifier(Ctx, OuterNS, WithGlobalNsPrefix);
296 } else if (const auto *TD = dyn_cast<TagDecl>(Outer)) {
297 return createNestedNameSpecifier(
298 Ctx, TD, FullyQualified, WithGlobalNsPrefix);
299 } else if (dyn_cast<TranslationUnitDecl>(Outer)) {
300 // Context is the TU. Nothing needs to be done.
301 return nullptr;
302 } else {
303 // Decl's context was neither the TU, a namespace, nor a
304 // TagDecl, which means it is a type local to a scope, and not
305 // accessible at the end of the TU.
306 return nullptr;
307 }
308 } else if (WithGlobalNsPrefix && DC->isTranslationUnit()) {
309 return NestedNameSpecifier::GlobalSpecifier(Ctx);
310 }
311 return nullptr;
312 }
313
314 /// Create a nested name specifier for the declaring context of
315 /// the type.
createNestedNameSpecifierForScopeOf(const ASTContext & Ctx,const Type * TypePtr,bool FullyQualified,bool WithGlobalNsPrefix)316 static NestedNameSpecifier *createNestedNameSpecifierForScopeOf(
317 const ASTContext &Ctx, const Type *TypePtr,
318 bool FullyQualified, bool WithGlobalNsPrefix) {
319 if (!TypePtr) return nullptr;
320
321 Decl *Decl = nullptr;
322 // There are probably other cases ...
323 if (const auto *TDT = dyn_cast<TypedefType>(TypePtr)) {
324 Decl = TDT->getDecl();
325 } else if (const auto *TagDeclType = dyn_cast<TagType>(TypePtr)) {
326 Decl = TagDeclType->getDecl();
327 } else if (const auto *TST = dyn_cast<TemplateSpecializationType>(TypePtr)) {
328 Decl = TST->getTemplateName().getAsTemplateDecl();
329 } else {
330 Decl = TypePtr->getAsCXXRecordDecl();
331 }
332
333 if (!Decl) return nullptr;
334
335 return createNestedNameSpecifierForScopeOf(
336 Ctx, Decl, FullyQualified, WithGlobalNsPrefix);
337 }
338
createNestedNameSpecifier(const ASTContext & Ctx,const NamespaceDecl * Namespace,bool WithGlobalNsPrefix)339 NestedNameSpecifier *createNestedNameSpecifier(const ASTContext &Ctx,
340 const NamespaceDecl *Namespace,
341 bool WithGlobalNsPrefix) {
342 while (Namespace && Namespace->isInline()) {
343 // Ignore inline namespace;
344 Namespace = dyn_cast<NamespaceDecl>(Namespace->getDeclContext());
345 }
346 if (!Namespace) return nullptr;
347
348 bool FullyQualified = true; // doesn't matter, DeclContexts are namespaces
349 return NestedNameSpecifier::Create(
350 Ctx,
351 createOuterNNS(Ctx, Namespace, FullyQualified, WithGlobalNsPrefix),
352 Namespace);
353 }
354
createNestedNameSpecifier(const ASTContext & Ctx,const TypeDecl * TD,bool FullyQualify,bool WithGlobalNsPrefix)355 NestedNameSpecifier *createNestedNameSpecifier(const ASTContext &Ctx,
356 const TypeDecl *TD,
357 bool FullyQualify,
358 bool WithGlobalNsPrefix) {
359 return NestedNameSpecifier::Create(
360 Ctx,
361 createOuterNNS(Ctx, TD, FullyQualify, WithGlobalNsPrefix),
362 false /*No TemplateKeyword*/,
363 TD->getTypeForDecl());
364 }
365
366 /// Return the fully qualified type, including fully-qualified
367 /// versions of any template parameters.
getFullyQualifiedType(QualType QT,const ASTContext & Ctx,bool WithGlobalNsPrefix)368 QualType getFullyQualifiedType(QualType QT, const ASTContext &Ctx,
369 bool WithGlobalNsPrefix) {
370 // In case of myType* we need to strip the pointer first, fully
371 // qualify and attach the pointer once again.
372 if (isa<PointerType>(QT.getTypePtr())) {
373 // Get the qualifiers.
374 Qualifiers Quals = QT.getQualifiers();
375 QT = getFullyQualifiedType(QT->getPointeeType(), Ctx, WithGlobalNsPrefix);
376 QT = Ctx.getPointerType(QT, QT->isCHERICapabilityType(Ctx)
377 ? PIK_Capability : PIK_Integer);
378 // Add back the qualifiers.
379 QT = Ctx.getQualifiedType(QT, Quals);
380 return QT;
381 }
382
383 if (auto *MPT = dyn_cast<MemberPointerType>(QT.getTypePtr())) {
384 // Get the qualifiers.
385 Qualifiers Quals = QT.getQualifiers();
386 // Fully qualify the pointee and class types.
387 QT = getFullyQualifiedType(QT->getPointeeType(), Ctx, WithGlobalNsPrefix);
388 QualType Class = getFullyQualifiedType(QualType(MPT->getClass(), 0), Ctx,
389 WithGlobalNsPrefix);
390 QT = Ctx.getMemberPointerType(QT, Class.getTypePtr());
391 // Add back the qualifiers.
392 QT = Ctx.getQualifiedType(QT, Quals);
393 return QT;
394 }
395
396 // In case of myType& we need to strip the reference first, fully
397 // qualify and attach the reference once again.
398 if (isa<ReferenceType>(QT.getTypePtr())) {
399 // Get the qualifiers.
400 bool IsLValueRefTy = isa<LValueReferenceType>(QT.getTypePtr());
401 Qualifiers Quals = QT.getQualifiers();
402 QT = getFullyQualifiedType(QT->getPointeeType(), Ctx, WithGlobalNsPrefix);
403 // Add the r- or l-value reference type back to the fully
404 // qualified one.
405 if (IsLValueRefTy)
406 QT = Ctx.getLValueReferenceType(QT);
407 else
408 QT = Ctx.getRValueReferenceType(QT);
409 // Add back the qualifiers.
410 QT = Ctx.getQualifiedType(QT, Quals);
411 return QT;
412 }
413
414 // Remove the part of the type related to the type being a template
415 // parameter (we won't report it as part of the 'type name' and it
416 // is actually make the code below to be more complex (to handle
417 // those)
418 while (isa<SubstTemplateTypeParmType>(QT.getTypePtr())) {
419 // Get the qualifiers.
420 Qualifiers Quals = QT.getQualifiers();
421
422 QT = cast<SubstTemplateTypeParmType>(QT.getTypePtr())->desugar();
423
424 // Add back the qualifiers.
425 QT = Ctx.getQualifiedType(QT, Quals);
426 }
427
428 NestedNameSpecifier *Prefix = nullptr;
429 // Local qualifiers are attached to the QualType outside of the
430 // elaborated type. Retrieve them before descending into the
431 // elaborated type.
432 Qualifiers PrefixQualifiers = QT.getLocalQualifiers();
433 QT = QualType(QT.getTypePtr(), 0);
434 ElaboratedTypeKeyword Keyword = ETK_None;
435 if (const auto *ETypeInput = dyn_cast<ElaboratedType>(QT.getTypePtr())) {
436 QT = ETypeInput->getNamedType();
437 assert(!QT.hasLocalQualifiers());
438 Keyword = ETypeInput->getKeyword();
439 }
440 // Create a nested name specifier if needed.
441 Prefix = createNestedNameSpecifierForScopeOf(Ctx, QT.getTypePtr(),
442 true /*FullyQualified*/,
443 WithGlobalNsPrefix);
444
445 // In case of template specializations iterate over the arguments and
446 // fully qualify them as well.
447 if (isa<const TemplateSpecializationType>(QT.getTypePtr()) ||
448 isa<const RecordType>(QT.getTypePtr())) {
449 // We are asked to fully qualify and we have a Record Type (which
450 // may point to a template specialization) or Template
451 // Specialization Type. We need to fully qualify their arguments.
452
453 const Type *TypePtr = getFullyQualifiedTemplateType(
454 Ctx, QT.getTypePtr(), WithGlobalNsPrefix);
455 QT = QualType(TypePtr, 0);
456 }
457 if (Prefix || Keyword != ETK_None) {
458 QT = Ctx.getElaboratedType(Keyword, Prefix, QT);
459 }
460 QT = Ctx.getQualifiedType(QT, PrefixQualifiers);
461 return QT;
462 }
463
getFullyQualifiedName(QualType QT,const ASTContext & Ctx,const PrintingPolicy & Policy,bool WithGlobalNsPrefix)464 std::string getFullyQualifiedName(QualType QT,
465 const ASTContext &Ctx,
466 const PrintingPolicy &Policy,
467 bool WithGlobalNsPrefix) {
468 QualType FQQT = getFullyQualifiedType(QT, Ctx, WithGlobalNsPrefix);
469 return FQQT.getAsString(Policy);
470 }
471
472 } // end namespace TypeName
473 } // end namespace clang
474