1 //===- DeclBase.cpp - Declaration AST Node 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 Decl and DeclContext classes.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "clang/AST/DeclBase.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/ASTLambda.h"
16 #include "clang/AST/ASTMutationListener.h"
17 #include "clang/AST/Attr.h"
18 #include "clang/AST/AttrIterator.h"
19 #include "clang/AST/Decl.h"
20 #include "clang/AST/DeclCXX.h"
21 #include "clang/AST/DeclContextInternals.h"
22 #include "clang/AST/DeclFriend.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/DeclOpenMP.h"
25 #include "clang/AST/DeclTemplate.h"
26 #include "clang/AST/DependentDiagnostic.h"
27 #include "clang/AST/ExternalASTSource.h"
28 #include "clang/AST/Stmt.h"
29 #include "clang/AST/Type.h"
30 #include "clang/Basic/IdentifierTable.h"
31 #include "clang/Basic/LLVM.h"
32 #include "clang/Basic/Module.h"
33 #include "clang/Basic/ObjCRuntime.h"
34 #include "clang/Basic/PartialDiagnostic.h"
35 #include "clang/Basic/SourceLocation.h"
36 #include "clang/Basic/TargetInfo.h"
37 #include "llvm/ADT/ArrayRef.h"
38 #include "llvm/ADT/PointerIntPair.h"
39 #include "llvm/ADT/SmallVector.h"
40 #include "llvm/ADT/StringRef.h"
41 #include "llvm/Support/Casting.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include "llvm/Support/MathExtras.h"
44 #include "llvm/Support/VersionTuple.h"
45 #include "llvm/Support/raw_ostream.h"
46 #include <algorithm>
47 #include <cassert>
48 #include <cstddef>
49 #include <string>
50 #include <tuple>
51 #include <utility>
52
53 using namespace clang;
54
55 //===----------------------------------------------------------------------===//
56 // Statistics
57 //===----------------------------------------------------------------------===//
58
59 #define DECL(DERIVED, BASE) static int n##DERIVED##s = 0;
60 #define ABSTRACT_DECL(DECL)
61 #include "clang/AST/DeclNodes.inc"
62
updateOutOfDate(IdentifierInfo & II) const63 void Decl::updateOutOfDate(IdentifierInfo &II) const {
64 getASTContext().getExternalSource()->updateOutOfDateIdentifier(II);
65 }
66
67 #define DECL(DERIVED, BASE) \
68 static_assert(alignof(Decl) >= alignof(DERIVED##Decl), \
69 "Alignment sufficient after objects prepended to " #DERIVED);
70 #define ABSTRACT_DECL(DECL)
71 #include "clang/AST/DeclNodes.inc"
72
operator new(std::size_t Size,const ASTContext & Context,unsigned ID,std::size_t Extra)73 void *Decl::operator new(std::size_t Size, const ASTContext &Context,
74 unsigned ID, std::size_t Extra) {
75 // Allocate an extra 8 bytes worth of storage, which ensures that the
76 // resulting pointer will still be 8-byte aligned.
77 static_assert(sizeof(unsigned) * 2 >= alignof(Decl),
78 "Decl won't be misaligned");
79 void *Start = Context.Allocate(Size + Extra + 8);
80 void *Result = (char*)Start + 8;
81
82 unsigned *PrefixPtr = (unsigned *)Result - 2;
83
84 // Zero out the first 4 bytes; this is used to store the owning module ID.
85 PrefixPtr[0] = 0;
86
87 // Store the global declaration ID in the second 4 bytes.
88 PrefixPtr[1] = ID;
89
90 return Result;
91 }
92
operator new(std::size_t Size,const ASTContext & Ctx,DeclContext * Parent,std::size_t Extra)93 void *Decl::operator new(std::size_t Size, const ASTContext &Ctx,
94 DeclContext *Parent, std::size_t Extra) {
95 assert(!Parent || &Parent->getParentASTContext() == &Ctx);
96 // With local visibility enabled, we track the owning module even for local
97 // declarations. We create the TU decl early and may not yet know what the
98 // LangOpts are, so conservatively allocate the storage.
99 if (Ctx.getLangOpts().trackLocalOwningModule() || !Parent) {
100 // Ensure required alignment of the resulting object by adding extra
101 // padding at the start if required.
102 size_t ExtraAlign =
103 llvm::offsetToAlignment(sizeof(Module *), llvm::Align(alignof(Decl)));
104 auto *Buffer = reinterpret_cast<char *>(
105 ::operator new(ExtraAlign + sizeof(Module *) + Size + Extra, Ctx));
106 Buffer += ExtraAlign;
107 auto *ParentModule =
108 Parent ? cast<Decl>(Parent)->getOwningModule() : nullptr;
109 return new (Buffer) Module*(ParentModule) + 1;
110 }
111 return ::operator new(Size + Extra, Ctx);
112 }
113
getOwningModuleSlow() const114 Module *Decl::getOwningModuleSlow() const {
115 assert(isFromASTFile() && "Not from AST file?");
116 return getASTContext().getExternalSource()->getModule(getOwningModuleID());
117 }
118
hasLocalOwningModuleStorage() const119 bool Decl::hasLocalOwningModuleStorage() const {
120 return getASTContext().getLangOpts().trackLocalOwningModule();
121 }
122
getDeclKindName() const123 const char *Decl::getDeclKindName() const {
124 switch (DeclKind) {
125 default: llvm_unreachable("Declaration not in DeclNodes.inc!");
126 #define DECL(DERIVED, BASE) case DERIVED: return #DERIVED;
127 #define ABSTRACT_DECL(DECL)
128 #include "clang/AST/DeclNodes.inc"
129 }
130 }
131
setInvalidDecl(bool Invalid)132 void Decl::setInvalidDecl(bool Invalid) {
133 InvalidDecl = Invalid;
134 assert(!isa<TagDecl>(this) || !cast<TagDecl>(this)->isCompleteDefinition());
135 if (!Invalid) {
136 return;
137 }
138
139 if (!isa<ParmVarDecl>(this)) {
140 // Defensive maneuver for ill-formed code: we're likely not to make it to
141 // a point where we set the access specifier, so default it to "public"
142 // to avoid triggering asserts elsewhere in the front end.
143 setAccess(AS_public);
144 }
145
146 // Marking a DecompositionDecl as invalid implies all the child BindingDecl's
147 // are invalid too.
148 if (auto *DD = dyn_cast<DecompositionDecl>(this)) {
149 for (auto *Binding : DD->bindings()) {
150 Binding->setInvalidDecl();
151 }
152 }
153 }
154
hasValidDeclKind() const155 bool DeclContext::hasValidDeclKind() const {
156 switch (getDeclKind()) {
157 #define DECL(DERIVED, BASE) case Decl::DERIVED: return true;
158 #define ABSTRACT_DECL(DECL)
159 #include "clang/AST/DeclNodes.inc"
160 }
161 return false;
162 }
163
getDeclKindName() const164 const char *DeclContext::getDeclKindName() const {
165 switch (getDeclKind()) {
166 #define DECL(DERIVED, BASE) case Decl::DERIVED: return #DERIVED;
167 #define ABSTRACT_DECL(DECL)
168 #include "clang/AST/DeclNodes.inc"
169 }
170 llvm_unreachable("Declaration context not in DeclNodes.inc!");
171 }
172
173 bool Decl::StatisticsEnabled = false;
EnableStatistics()174 void Decl::EnableStatistics() {
175 StatisticsEnabled = true;
176 }
177
PrintStats()178 void Decl::PrintStats() {
179 llvm::errs() << "\n*** Decl Stats:\n";
180
181 int totalDecls = 0;
182 #define DECL(DERIVED, BASE) totalDecls += n##DERIVED##s;
183 #define ABSTRACT_DECL(DECL)
184 #include "clang/AST/DeclNodes.inc"
185 llvm::errs() << " " << totalDecls << " decls total.\n";
186
187 int totalBytes = 0;
188 #define DECL(DERIVED, BASE) \
189 if (n##DERIVED##s > 0) { \
190 totalBytes += (int)(n##DERIVED##s * sizeof(DERIVED##Decl)); \
191 llvm::errs() << " " << n##DERIVED##s << " " #DERIVED " decls, " \
192 << sizeof(DERIVED##Decl) << " each (" \
193 << n##DERIVED##s * sizeof(DERIVED##Decl) \
194 << " bytes)\n"; \
195 }
196 #define ABSTRACT_DECL(DECL)
197 #include "clang/AST/DeclNodes.inc"
198
199 llvm::errs() << "Total bytes = " << totalBytes << "\n";
200 }
201
add(Kind k)202 void Decl::add(Kind k) {
203 switch (k) {
204 #define DECL(DERIVED, BASE) case DERIVED: ++n##DERIVED##s; break;
205 #define ABSTRACT_DECL(DECL)
206 #include "clang/AST/DeclNodes.inc"
207 }
208 }
209
isTemplateParameterPack() const210 bool Decl::isTemplateParameterPack() const {
211 if (const auto *TTP = dyn_cast<TemplateTypeParmDecl>(this))
212 return TTP->isParameterPack();
213 if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(this))
214 return NTTP->isParameterPack();
215 if (const auto *TTP = dyn_cast<TemplateTemplateParmDecl>(this))
216 return TTP->isParameterPack();
217 return false;
218 }
219
isParameterPack() const220 bool Decl::isParameterPack() const {
221 if (const auto *Var = dyn_cast<VarDecl>(this))
222 return Var->isParameterPack();
223
224 return isTemplateParameterPack();
225 }
226
getAsFunction()227 FunctionDecl *Decl::getAsFunction() {
228 if (auto *FD = dyn_cast<FunctionDecl>(this))
229 return FD;
230 if (const auto *FTD = dyn_cast<FunctionTemplateDecl>(this))
231 return FTD->getTemplatedDecl();
232 return nullptr;
233 }
234
isTemplateDecl() const235 bool Decl::isTemplateDecl() const {
236 return isa<TemplateDecl>(this);
237 }
238
getDescribedTemplate() const239 TemplateDecl *Decl::getDescribedTemplate() const {
240 if (auto *FD = dyn_cast<FunctionDecl>(this))
241 return FD->getDescribedFunctionTemplate();
242 if (auto *RD = dyn_cast<CXXRecordDecl>(this))
243 return RD->getDescribedClassTemplate();
244 if (auto *VD = dyn_cast<VarDecl>(this))
245 return VD->getDescribedVarTemplate();
246 if (auto *AD = dyn_cast<TypeAliasDecl>(this))
247 return AD->getDescribedAliasTemplate();
248
249 return nullptr;
250 }
251
getDescribedTemplateParams() const252 const TemplateParameterList *Decl::getDescribedTemplateParams() const {
253 if (auto *TD = getDescribedTemplate())
254 return TD->getTemplateParameters();
255 if (auto *CTPSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(this))
256 return CTPSD->getTemplateParameters();
257 if (auto *VTPSD = dyn_cast<VarTemplatePartialSpecializationDecl>(this))
258 return VTPSD->getTemplateParameters();
259 return nullptr;
260 }
261
isTemplated() const262 bool Decl::isTemplated() const {
263 // A declaration is templated if it is a template or a template pattern, or
264 // is within (lexcially for a friend or local function declaration,
265 // semantically otherwise) a dependent context.
266 if (auto *AsDC = dyn_cast<DeclContext>(this))
267 return AsDC->isDependentContext();
268 auto *DC = getFriendObjectKind() || isLocalExternDecl()
269 ? getLexicalDeclContext() : getDeclContext();
270 return DC->isDependentContext() || isTemplateDecl() ||
271 getDescribedTemplateParams();
272 }
273
getTemplateDepth() const274 unsigned Decl::getTemplateDepth() const {
275 if (auto *DC = dyn_cast<DeclContext>(this))
276 if (DC->isFileContext())
277 return 0;
278
279 if (auto *TPL = getDescribedTemplateParams())
280 return TPL->getDepth() + 1;
281
282 // If this is a dependent lambda, there might be an enclosing variable
283 // template. In this case, the next step is not the parent DeclContext (or
284 // even a DeclContext at all).
285 auto *RD = dyn_cast<CXXRecordDecl>(this);
286 if (RD && RD->isDependentLambda())
287 if (Decl *Context = RD->getLambdaContextDecl())
288 return Context->getTemplateDepth();
289
290 const DeclContext *DC =
291 getFriendObjectKind() ? getLexicalDeclContext() : getDeclContext();
292 return cast<Decl>(DC)->getTemplateDepth();
293 }
294
getParentFunctionOrMethod(bool LexicalParent) const295 const DeclContext *Decl::getParentFunctionOrMethod(bool LexicalParent) const {
296 for (const DeclContext *DC = LexicalParent ? getLexicalDeclContext()
297 : getDeclContext();
298 DC && !DC->isFileContext(); DC = DC->getParent())
299 if (DC->isFunctionOrMethod())
300 return DC;
301
302 return nullptr;
303 }
304
305 //===----------------------------------------------------------------------===//
306 // PrettyStackTraceDecl Implementation
307 //===----------------------------------------------------------------------===//
308
print(raw_ostream & OS) const309 void PrettyStackTraceDecl::print(raw_ostream &OS) const {
310 SourceLocation TheLoc = Loc;
311 if (TheLoc.isInvalid() && TheDecl)
312 TheLoc = TheDecl->getLocation();
313
314 if (TheLoc.isValid()) {
315 TheLoc.print(OS, SM);
316 OS << ": ";
317 }
318
319 OS << Message;
320
321 if (const auto *DN = dyn_cast_or_null<NamedDecl>(TheDecl)) {
322 OS << " '";
323 DN->printQualifiedName(OS);
324 OS << '\'';
325 }
326 OS << '\n';
327 }
328
329 //===----------------------------------------------------------------------===//
330 // Decl Implementation
331 //===----------------------------------------------------------------------===//
332
333 // Out-of-line virtual method providing a home for Decl.
334 Decl::~Decl() = default;
335
setDeclContext(DeclContext * DC)336 void Decl::setDeclContext(DeclContext *DC) {
337 DeclCtx = DC;
338 }
339
setLexicalDeclContext(DeclContext * DC)340 void Decl::setLexicalDeclContext(DeclContext *DC) {
341 if (DC == getLexicalDeclContext())
342 return;
343
344 if (isInSemaDC()) {
345 setDeclContextsImpl(getDeclContext(), DC, getASTContext());
346 } else {
347 getMultipleDC()->LexicalDC = DC;
348 }
349
350 // FIXME: We shouldn't be changing the lexical context of declarations
351 // imported from AST files.
352 if (!isFromASTFile()) {
353 setModuleOwnershipKind(getModuleOwnershipKindForChildOf(DC));
354 if (hasOwningModule())
355 setLocalOwningModule(cast<Decl>(DC)->getOwningModule());
356 }
357
358 assert(
359 (getModuleOwnershipKind() != ModuleOwnershipKind::VisibleWhenImported ||
360 getOwningModule()) &&
361 "hidden declaration has no owning module");
362 }
363
setDeclContextsImpl(DeclContext * SemaDC,DeclContext * LexicalDC,ASTContext & Ctx)364 void Decl::setDeclContextsImpl(DeclContext *SemaDC, DeclContext *LexicalDC,
365 ASTContext &Ctx) {
366 if (SemaDC == LexicalDC) {
367 DeclCtx = SemaDC;
368 } else {
369 auto *MDC = new (Ctx) Decl::MultipleDC();
370 MDC->SemanticDC = SemaDC;
371 MDC->LexicalDC = LexicalDC;
372 DeclCtx = MDC;
373 }
374 }
375
isInLocalScopeForInstantiation() const376 bool Decl::isInLocalScopeForInstantiation() const {
377 const DeclContext *LDC = getLexicalDeclContext();
378 if (!LDC->isDependentContext())
379 return false;
380 while (true) {
381 if (LDC->isFunctionOrMethod())
382 return true;
383 if (!isa<TagDecl>(LDC))
384 return false;
385 if (const auto *CRD = dyn_cast<CXXRecordDecl>(LDC))
386 if (CRD->isLambda())
387 return true;
388 LDC = LDC->getLexicalParent();
389 }
390 return false;
391 }
392
isInAnonymousNamespace() const393 bool Decl::isInAnonymousNamespace() const {
394 for (const DeclContext *DC = getDeclContext(); DC; DC = DC->getParent()) {
395 if (const auto *ND = dyn_cast<NamespaceDecl>(DC))
396 if (ND->isAnonymousNamespace())
397 return true;
398 }
399
400 return false;
401 }
402
isInStdNamespace() const403 bool Decl::isInStdNamespace() const {
404 const DeclContext *DC = getDeclContext();
405 return DC && DC->isStdNamespace();
406 }
407
isFileContextDecl() const408 bool Decl::isFileContextDecl() const {
409 const auto *DC = dyn_cast<DeclContext>(this);
410 return DC && DC->isFileContext();
411 }
412
isFlexibleArrayMemberLike(ASTContext & Ctx,const Decl * D,QualType Ty,LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel,bool IgnoreTemplateOrMacroSubstitution)413 bool Decl::isFlexibleArrayMemberLike(
414 ASTContext &Ctx, const Decl *D, QualType Ty,
415 LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel,
416 bool IgnoreTemplateOrMacroSubstitution) {
417 // For compatibility with existing code, we treat arrays of length 0 or
418 // 1 as flexible array members.
419 const auto *CAT = Ctx.getAsConstantArrayType(Ty);
420 if (CAT) {
421 using FAMKind = LangOptions::StrictFlexArraysLevelKind;
422
423 llvm::APInt Size = CAT->getSize();
424 if (StrictFlexArraysLevel == FAMKind::IncompleteOnly)
425 return false;
426
427 // GCC extension, only allowed to represent a FAM.
428 if (Size.isZero())
429 return true;
430
431 if (StrictFlexArraysLevel == FAMKind::ZeroOrIncomplete && Size.uge(1))
432 return false;
433
434 if (StrictFlexArraysLevel == FAMKind::OneZeroOrIncomplete && Size.uge(2))
435 return false;
436 } else if (!Ctx.getAsIncompleteArrayType(Ty)) {
437 return false;
438 }
439
440 if (const auto *OID = dyn_cast_if_present<ObjCIvarDecl>(D))
441 return OID->getNextIvar() == nullptr;
442
443 const auto *FD = dyn_cast_if_present<FieldDecl>(D);
444 if (!FD)
445 return false;
446
447 if (CAT) {
448 // GCC treats an array memeber of a union as an FAM if the size is one or
449 // zero.
450 llvm::APInt Size = CAT->getSize();
451 if (FD->getParent()->isUnion() && (Size.isZero() || Size.isOne()))
452 return true;
453 }
454
455 // Don't consider sizes resulting from macro expansions or template argument
456 // substitution to form C89 tail-padded arrays.
457 if (IgnoreTemplateOrMacroSubstitution) {
458 TypeSourceInfo *TInfo = FD->getTypeSourceInfo();
459 while (TInfo) {
460 TypeLoc TL = TInfo->getTypeLoc();
461
462 // Look through typedefs.
463 if (TypedefTypeLoc TTL = TL.getAsAdjusted<TypedefTypeLoc>()) {
464 const TypedefNameDecl *TDL = TTL.getTypedefNameDecl();
465 TInfo = TDL->getTypeSourceInfo();
466 continue;
467 }
468
469 if (auto CTL = TL.getAs<ConstantArrayTypeLoc>()) {
470 if (const Expr *SizeExpr =
471 dyn_cast_if_present<IntegerLiteral>(CTL.getSizeExpr());
472 !SizeExpr || SizeExpr->getExprLoc().isMacroID())
473 return false;
474 }
475
476 break;
477 }
478 }
479
480 // Test that the field is the last in the structure.
481 RecordDecl::field_iterator FI(
482 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
483 return ++FI == FD->getParent()->field_end();
484 }
485
getTranslationUnitDecl()486 TranslationUnitDecl *Decl::getTranslationUnitDecl() {
487 if (auto *TUD = dyn_cast<TranslationUnitDecl>(this))
488 return TUD;
489
490 DeclContext *DC = getDeclContext();
491 assert(DC && "This decl is not contained in a translation unit!");
492
493 while (!DC->isTranslationUnit()) {
494 DC = DC->getParent();
495 assert(DC && "This decl is not contained in a translation unit!");
496 }
497
498 return cast<TranslationUnitDecl>(DC);
499 }
500
getASTContext() const501 ASTContext &Decl::getASTContext() const {
502 return getTranslationUnitDecl()->getASTContext();
503 }
504
505 /// Helper to get the language options from the ASTContext.
506 /// Defined out of line to avoid depending on ASTContext.h.
getLangOpts() const507 const LangOptions &Decl::getLangOpts() const {
508 return getASTContext().getLangOpts();
509 }
510
getASTMutationListener() const511 ASTMutationListener *Decl::getASTMutationListener() const {
512 return getASTContext().getASTMutationListener();
513 }
514
getMaxAlignment() const515 unsigned Decl::getMaxAlignment() const {
516 if (!hasAttrs())
517 return 0;
518
519 unsigned Align = 0;
520 const AttrVec &V = getAttrs();
521 ASTContext &Ctx = getASTContext();
522 specific_attr_iterator<AlignedAttr> I(V.begin()), E(V.end());
523 for (; I != E; ++I) {
524 if (!I->isAlignmentErrorDependent())
525 Align = std::max(Align, I->getAlignment(Ctx));
526 }
527 return Align;
528 }
529
isUsed(bool CheckUsedAttr) const530 bool Decl::isUsed(bool CheckUsedAttr) const {
531 const Decl *CanonD = getCanonicalDecl();
532 if (CanonD->Used)
533 return true;
534
535 // Check for used attribute.
536 // Ask the most recent decl, since attributes accumulate in the redecl chain.
537 if (CheckUsedAttr && getMostRecentDecl()->hasAttr<UsedAttr>())
538 return true;
539
540 // The information may have not been deserialized yet. Force deserialization
541 // to complete the needed information.
542 return getMostRecentDecl()->getCanonicalDecl()->Used;
543 }
544
markUsed(ASTContext & C)545 void Decl::markUsed(ASTContext &C) {
546 if (isUsed(false))
547 return;
548
549 if (C.getASTMutationListener())
550 C.getASTMutationListener()->DeclarationMarkedUsed(this);
551
552 setIsUsed();
553 }
554
isReferenced() const555 bool Decl::isReferenced() const {
556 if (Referenced)
557 return true;
558
559 // Check redeclarations.
560 for (const auto *I : redecls())
561 if (I->Referenced)
562 return true;
563
564 return false;
565 }
566
getExternalSourceSymbolAttr() const567 ExternalSourceSymbolAttr *Decl::getExternalSourceSymbolAttr() const {
568 const Decl *Definition = nullptr;
569 if (auto *ID = dyn_cast<ObjCInterfaceDecl>(this)) {
570 Definition = ID->getDefinition();
571 } else if (auto *PD = dyn_cast<ObjCProtocolDecl>(this)) {
572 Definition = PD->getDefinition();
573 } else if (auto *TD = dyn_cast<TagDecl>(this)) {
574 Definition = TD->getDefinition();
575 }
576 if (!Definition)
577 Definition = this;
578
579 if (auto *attr = Definition->getAttr<ExternalSourceSymbolAttr>())
580 return attr;
581 if (auto *dcd = dyn_cast<Decl>(getDeclContext())) {
582 return dcd->getAttr<ExternalSourceSymbolAttr>();
583 }
584
585 return nullptr;
586 }
587
hasDefiningAttr() const588 bool Decl::hasDefiningAttr() const {
589 return hasAttr<AliasAttr>() || hasAttr<IFuncAttr>() ||
590 hasAttr<LoaderUninitializedAttr>();
591 }
592
getDefiningAttr() const593 const Attr *Decl::getDefiningAttr() const {
594 if (auto *AA = getAttr<AliasAttr>())
595 return AA;
596 if (auto *IFA = getAttr<IFuncAttr>())
597 return IFA;
598 if (auto *NZA = getAttr<LoaderUninitializedAttr>())
599 return NZA;
600 return nullptr;
601 }
602
getRealizedPlatform(const AvailabilityAttr * A,const ASTContext & Context)603 static StringRef getRealizedPlatform(const AvailabilityAttr *A,
604 const ASTContext &Context) {
605 // Check if this is an App Extension "platform", and if so chop off
606 // the suffix for matching with the actual platform.
607 StringRef RealizedPlatform = A->getPlatform()->getName();
608 if (!Context.getLangOpts().AppExt)
609 return RealizedPlatform;
610 size_t suffix = RealizedPlatform.rfind("_app_extension");
611 if (suffix != StringRef::npos)
612 return RealizedPlatform.slice(0, suffix);
613 return RealizedPlatform;
614 }
615
616 /// Determine the availability of the given declaration based on
617 /// the target platform.
618 ///
619 /// When it returns an availability result other than \c AR_Available,
620 /// if the \p Message parameter is non-NULL, it will be set to a
621 /// string describing why the entity is unavailable.
622 ///
623 /// FIXME: Make these strings localizable, since they end up in
624 /// diagnostics.
CheckAvailability(ASTContext & Context,const AvailabilityAttr * A,std::string * Message,VersionTuple EnclosingVersion)625 static AvailabilityResult CheckAvailability(ASTContext &Context,
626 const AvailabilityAttr *A,
627 std::string *Message,
628 VersionTuple EnclosingVersion) {
629 if (EnclosingVersion.empty())
630 EnclosingVersion = Context.getTargetInfo().getPlatformMinVersion();
631
632 if (EnclosingVersion.empty())
633 return AR_Available;
634
635 StringRef ActualPlatform = A->getPlatform()->getName();
636 StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
637
638 // Match the platform name.
639 if (getRealizedPlatform(A, Context) != TargetPlatform)
640 return AR_Available;
641
642 StringRef PrettyPlatformName
643 = AvailabilityAttr::getPrettyPlatformName(ActualPlatform);
644
645 if (PrettyPlatformName.empty())
646 PrettyPlatformName = ActualPlatform;
647
648 std::string HintMessage;
649 if (!A->getMessage().empty()) {
650 HintMessage = " - ";
651 HintMessage += A->getMessage();
652 }
653
654 // Make sure that this declaration has not been marked 'unavailable'.
655 if (A->getUnavailable()) {
656 if (Message) {
657 Message->clear();
658 llvm::raw_string_ostream Out(*Message);
659 Out << "not available on " << PrettyPlatformName
660 << HintMessage;
661 }
662
663 return AR_Unavailable;
664 }
665
666 // Make sure that this declaration has already been introduced.
667 if (!A->getIntroduced().empty() &&
668 EnclosingVersion < A->getIntroduced()) {
669 if (Message) {
670 Message->clear();
671 llvm::raw_string_ostream Out(*Message);
672 VersionTuple VTI(A->getIntroduced());
673 Out << "introduced in " << PrettyPlatformName << ' '
674 << VTI << HintMessage;
675 }
676
677 return A->getStrict() ? AR_Unavailable : AR_NotYetIntroduced;
678 }
679
680 // Make sure that this declaration hasn't been obsoleted.
681 if (!A->getObsoleted().empty() && EnclosingVersion >= A->getObsoleted()) {
682 if (Message) {
683 Message->clear();
684 llvm::raw_string_ostream Out(*Message);
685 VersionTuple VTO(A->getObsoleted());
686 Out << "obsoleted in " << PrettyPlatformName << ' '
687 << VTO << HintMessage;
688 }
689
690 return AR_Unavailable;
691 }
692
693 // Make sure that this declaration hasn't been deprecated.
694 if (!A->getDeprecated().empty() && EnclosingVersion >= A->getDeprecated()) {
695 if (Message) {
696 Message->clear();
697 llvm::raw_string_ostream Out(*Message);
698 VersionTuple VTD(A->getDeprecated());
699 Out << "first deprecated in " << PrettyPlatformName << ' '
700 << VTD << HintMessage;
701 }
702
703 return AR_Deprecated;
704 }
705
706 return AR_Available;
707 }
708
getAvailability(std::string * Message,VersionTuple EnclosingVersion,StringRef * RealizedPlatform) const709 AvailabilityResult Decl::getAvailability(std::string *Message,
710 VersionTuple EnclosingVersion,
711 StringRef *RealizedPlatform) const {
712 if (auto *FTD = dyn_cast<FunctionTemplateDecl>(this))
713 return FTD->getTemplatedDecl()->getAvailability(Message, EnclosingVersion,
714 RealizedPlatform);
715
716 AvailabilityResult Result = AR_Available;
717 std::string ResultMessage;
718
719 for (const auto *A : attrs()) {
720 if (const auto *Deprecated = dyn_cast<DeprecatedAttr>(A)) {
721 if (Result >= AR_Deprecated)
722 continue;
723
724 if (Message)
725 ResultMessage = std::string(Deprecated->getMessage());
726
727 Result = AR_Deprecated;
728 continue;
729 }
730
731 if (const auto *Unavailable = dyn_cast<UnavailableAttr>(A)) {
732 if (Message)
733 *Message = std::string(Unavailable->getMessage());
734 return AR_Unavailable;
735 }
736
737 if (const auto *Availability = dyn_cast<AvailabilityAttr>(A)) {
738 AvailabilityResult AR = CheckAvailability(getASTContext(), Availability,
739 Message, EnclosingVersion);
740
741 if (AR == AR_Unavailable) {
742 if (RealizedPlatform)
743 *RealizedPlatform = Availability->getPlatform()->getName();
744 return AR_Unavailable;
745 }
746
747 if (AR > Result) {
748 Result = AR;
749 if (Message)
750 ResultMessage.swap(*Message);
751 }
752 continue;
753 }
754 }
755
756 if (Message)
757 Message->swap(ResultMessage);
758 return Result;
759 }
760
getVersionIntroduced() const761 VersionTuple Decl::getVersionIntroduced() const {
762 const ASTContext &Context = getASTContext();
763 StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
764 for (const auto *A : attrs()) {
765 if (const auto *Availability = dyn_cast<AvailabilityAttr>(A)) {
766 if (getRealizedPlatform(Availability, Context) != TargetPlatform)
767 continue;
768 if (!Availability->getIntroduced().empty())
769 return Availability->getIntroduced();
770 }
771 }
772 return {};
773 }
774
canBeWeakImported(bool & IsDefinition) const775 bool Decl::canBeWeakImported(bool &IsDefinition) const {
776 IsDefinition = false;
777
778 // Variables, if they aren't definitions.
779 if (const auto *Var = dyn_cast<VarDecl>(this)) {
780 if (Var->isThisDeclarationADefinition()) {
781 IsDefinition = true;
782 return false;
783 }
784 return true;
785 }
786 // Functions, if they aren't definitions.
787 if (const auto *FD = dyn_cast<FunctionDecl>(this)) {
788 if (FD->hasBody()) {
789 IsDefinition = true;
790 return false;
791 }
792 return true;
793
794 }
795 // Objective-C classes, if this is the non-fragile runtime.
796 if (isa<ObjCInterfaceDecl>(this) &&
797 getASTContext().getLangOpts().ObjCRuntime.hasWeakClassImport()) {
798 return true;
799 }
800 // Nothing else.
801 return false;
802 }
803
isWeakImported() const804 bool Decl::isWeakImported() const {
805 bool IsDefinition;
806 if (!canBeWeakImported(IsDefinition))
807 return false;
808
809 for (const auto *A : getMostRecentDecl()->attrs()) {
810 if (isa<WeakImportAttr>(A))
811 return true;
812
813 if (const auto *Availability = dyn_cast<AvailabilityAttr>(A)) {
814 if (CheckAvailability(getASTContext(), Availability, nullptr,
815 VersionTuple()) == AR_NotYetIntroduced)
816 return true;
817 }
818 }
819
820 return false;
821 }
822
getIdentifierNamespaceForKind(Kind DeclKind)823 unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
824 switch (DeclKind) {
825 case Function:
826 case CXXDeductionGuide:
827 case CXXMethod:
828 case CXXConstructor:
829 case ConstructorUsingShadow:
830 case CXXDestructor:
831 case CXXConversion:
832 case EnumConstant:
833 case Var:
834 case ImplicitParam:
835 case ParmVar:
836 case ObjCMethod:
837 case ObjCProperty:
838 case MSProperty:
839 case HLSLBuffer:
840 return IDNS_Ordinary;
841 case Label:
842 return IDNS_Label;
843 case IndirectField:
844 return IDNS_Ordinary | IDNS_Member;
845
846 case Binding:
847 case NonTypeTemplateParm:
848 case VarTemplate:
849 case Concept:
850 // These (C++-only) declarations are found by redeclaration lookup for
851 // tag types, so we include them in the tag namespace.
852 return IDNS_Ordinary | IDNS_Tag;
853
854 case ObjCCompatibleAlias:
855 case ObjCInterface:
856 return IDNS_Ordinary | IDNS_Type;
857
858 case Typedef:
859 case TypeAlias:
860 case TemplateTypeParm:
861 case ObjCTypeParam:
862 return IDNS_Ordinary | IDNS_Type;
863
864 case UnresolvedUsingTypename:
865 return IDNS_Ordinary | IDNS_Type | IDNS_Using;
866
867 case UsingShadow:
868 return 0; // we'll actually overwrite this later
869
870 case UnresolvedUsingValue:
871 return IDNS_Ordinary | IDNS_Using;
872
873 case Using:
874 case UsingPack:
875 case UsingEnum:
876 return IDNS_Using;
877
878 case ObjCProtocol:
879 return IDNS_ObjCProtocol;
880
881 case Field:
882 case ObjCAtDefsField:
883 case ObjCIvar:
884 return IDNS_Member;
885
886 case Record:
887 case CXXRecord:
888 case Enum:
889 return IDNS_Tag | IDNS_Type;
890
891 case Namespace:
892 case NamespaceAlias:
893 return IDNS_Namespace;
894
895 case FunctionTemplate:
896 return IDNS_Ordinary;
897
898 case ClassTemplate:
899 case TemplateTemplateParm:
900 case TypeAliasTemplate:
901 return IDNS_Ordinary | IDNS_Tag | IDNS_Type;
902
903 case UnresolvedUsingIfExists:
904 return IDNS_Type | IDNS_Ordinary;
905
906 case OMPDeclareReduction:
907 return IDNS_OMPReduction;
908
909 case OMPDeclareMapper:
910 return IDNS_OMPMapper;
911
912 // Never have names.
913 case Friend:
914 case FriendTemplate:
915 case AccessSpec:
916 case LinkageSpec:
917 case Export:
918 case FileScopeAsm:
919 case TopLevelStmt:
920 case StaticAssert:
921 case ObjCPropertyImpl:
922 case PragmaComment:
923 case PragmaDetectMismatch:
924 case Block:
925 case Captured:
926 case TranslationUnit:
927 case ExternCContext:
928 case Decomposition:
929 case MSGuid:
930 case UnnamedGlobalConstant:
931 case TemplateParamObject:
932
933 case UsingDirective:
934 case BuiltinTemplate:
935 case ClassTemplateSpecialization:
936 case ClassTemplatePartialSpecialization:
937 case VarTemplateSpecialization:
938 case VarTemplatePartialSpecialization:
939 case ObjCImplementation:
940 case ObjCCategory:
941 case ObjCCategoryImpl:
942 case Import:
943 case OMPThreadPrivate:
944 case OMPAllocate:
945 case OMPRequires:
946 case OMPCapturedExpr:
947 case Empty:
948 case LifetimeExtendedTemporary:
949 case RequiresExprBody:
950 case ImplicitConceptSpecialization:
951 // Never looked up by name.
952 return 0;
953 }
954
955 llvm_unreachable("Invalid DeclKind!");
956 }
957
setAttrsImpl(const AttrVec & attrs,ASTContext & Ctx)958 void Decl::setAttrsImpl(const AttrVec &attrs, ASTContext &Ctx) {
959 assert(!HasAttrs && "Decl already contains attrs.");
960
961 AttrVec &AttrBlank = Ctx.getDeclAttrs(this);
962 assert(AttrBlank.empty() && "HasAttrs was wrong?");
963
964 AttrBlank = attrs;
965 HasAttrs = true;
966 }
967
dropAttrs()968 void Decl::dropAttrs() {
969 if (!HasAttrs) return;
970
971 HasAttrs = false;
972 getASTContext().eraseDeclAttrs(this);
973 }
974
addAttr(Attr * A)975 void Decl::addAttr(Attr *A) {
976 if (!hasAttrs()) {
977 setAttrs(AttrVec(1, A));
978 return;
979 }
980
981 AttrVec &Attrs = getAttrs();
982 if (!A->isInherited()) {
983 Attrs.push_back(A);
984 return;
985 }
986
987 // Attribute inheritance is processed after attribute parsing. To keep the
988 // order as in the source code, add inherited attributes before non-inherited
989 // ones.
990 auto I = Attrs.begin(), E = Attrs.end();
991 for (; I != E; ++I) {
992 if (!(*I)->isInherited())
993 break;
994 }
995 Attrs.insert(I, A);
996 }
997
getAttrs() const998 const AttrVec &Decl::getAttrs() const {
999 assert(HasAttrs && "No attrs to get!");
1000 return getASTContext().getDeclAttrs(this);
1001 }
1002
castFromDeclContext(const DeclContext * D)1003 Decl *Decl::castFromDeclContext (const DeclContext *D) {
1004 Decl::Kind DK = D->getDeclKind();
1005 switch (DK) {
1006 #define DECL(NAME, BASE)
1007 #define DECL_CONTEXT(NAME) \
1008 case Decl::NAME: \
1009 return static_cast<NAME##Decl *>(const_cast<DeclContext *>(D));
1010 #include "clang/AST/DeclNodes.inc"
1011 default:
1012 llvm_unreachable("a decl that inherits DeclContext isn't handled");
1013 }
1014 }
1015
castToDeclContext(const Decl * D)1016 DeclContext *Decl::castToDeclContext(const Decl *D) {
1017 Decl::Kind DK = D->getKind();
1018 switch(DK) {
1019 #define DECL(NAME, BASE)
1020 #define DECL_CONTEXT(NAME) \
1021 case Decl::NAME: \
1022 return static_cast<NAME##Decl *>(const_cast<Decl *>(D));
1023 #include "clang/AST/DeclNodes.inc"
1024 default:
1025 llvm_unreachable("a decl that inherits DeclContext isn't handled");
1026 }
1027 }
1028
getBodyRBrace() const1029 SourceLocation Decl::getBodyRBrace() const {
1030 // Special handling of FunctionDecl to avoid de-serializing the body from PCH.
1031 // FunctionDecl stores EndRangeLoc for this purpose.
1032 if (const auto *FD = dyn_cast<FunctionDecl>(this)) {
1033 const FunctionDecl *Definition;
1034 if (FD->hasBody(Definition))
1035 return Definition->getSourceRange().getEnd();
1036 return {};
1037 }
1038
1039 if (Stmt *Body = getBody())
1040 return Body->getSourceRange().getEnd();
1041
1042 return {};
1043 }
1044
AccessDeclContextCheck() const1045 bool Decl::AccessDeclContextCheck() const {
1046 #ifndef NDEBUG
1047 // Suppress this check if any of the following hold:
1048 // 1. this is the translation unit (and thus has no parent)
1049 // 2. this is a template parameter (and thus doesn't belong to its context)
1050 // 3. this is a non-type template parameter
1051 // 4. the context is not a record
1052 // 5. it's invalid
1053 // 6. it's a C++0x static_assert.
1054 // 7. it's a block literal declaration
1055 // 8. it's a temporary with lifetime extended due to being default value.
1056 if (isa<TranslationUnitDecl>(this) || isa<TemplateTypeParmDecl>(this) ||
1057 isa<NonTypeTemplateParmDecl>(this) || !getDeclContext() ||
1058 !isa<CXXRecordDecl>(getDeclContext()) || isInvalidDecl() ||
1059 isa<StaticAssertDecl>(this) || isa<BlockDecl>(this) ||
1060 // FIXME: a ParmVarDecl can have ClassTemplateSpecialization
1061 // as DeclContext (?).
1062 isa<ParmVarDecl>(this) ||
1063 // FIXME: a ClassTemplateSpecialization or CXXRecordDecl can have
1064 // AS_none as access specifier.
1065 isa<CXXRecordDecl>(this) || isa<LifetimeExtendedTemporaryDecl>(this))
1066 return true;
1067
1068 assert(Access != AS_none &&
1069 "Access specifier is AS_none inside a record decl");
1070 #endif
1071 return true;
1072 }
1073
isInExportDeclContext() const1074 bool Decl::isInExportDeclContext() const {
1075 const DeclContext *DC = getLexicalDeclContext();
1076
1077 while (DC && !isa<ExportDecl>(DC))
1078 DC = DC->getLexicalParent();
1079
1080 return DC && isa<ExportDecl>(DC);
1081 }
1082
isInAnotherModuleUnit() const1083 bool Decl::isInAnotherModuleUnit() const {
1084 auto *M = getOwningModule();
1085
1086 if (!M)
1087 return false;
1088
1089 M = M->getTopLevelModule();
1090 // FIXME: It is problematic if the header module lives in another module
1091 // unit. Consider to fix this by techniques like
1092 // ExternalASTSource::hasExternalDefinitions.
1093 if (M->isHeaderLikeModule())
1094 return false;
1095
1096 // A global module without parent implies that we're parsing the global
1097 // module. So it can't be in another module unit.
1098 if (M->isGlobalModule())
1099 return false;
1100
1101 assert(M->isNamedModule() && "New module kind?");
1102 return M != getASTContext().getCurrentNamedModule();
1103 }
1104
shouldSkipCheckingODR() const1105 bool Decl::shouldSkipCheckingODR() const {
1106 return getASTContext().getLangOpts().SkipODRCheckInGMF && getOwningModule() &&
1107 getOwningModule()->isExplicitGlobalModule();
1108 }
1109
getKind(const Decl * D)1110 static Decl::Kind getKind(const Decl *D) { return D->getKind(); }
getKind(const DeclContext * DC)1111 static Decl::Kind getKind(const DeclContext *DC) { return DC->getDeclKind(); }
1112
getID() const1113 int64_t Decl::getID() const {
1114 return getASTContext().getAllocator().identifyKnownAlignedObject<Decl>(this);
1115 }
1116
getFunctionType(bool BlocksToo) const1117 const FunctionType *Decl::getFunctionType(bool BlocksToo) const {
1118 QualType Ty;
1119 if (const auto *D = dyn_cast<ValueDecl>(this))
1120 Ty = D->getType();
1121 else if (const auto *D = dyn_cast<TypedefNameDecl>(this))
1122 Ty = D->getUnderlyingType();
1123 else
1124 return nullptr;
1125
1126 if (Ty->isFunctionPointerType())
1127 Ty = Ty->castAs<PointerType>()->getPointeeType();
1128 else if (Ty->isFunctionReferenceType())
1129 Ty = Ty->castAs<ReferenceType>()->getPointeeType();
1130 else if (BlocksToo && Ty->isBlockPointerType())
1131 Ty = Ty->castAs<BlockPointerType>()->getPointeeType();
1132
1133 return Ty->getAs<FunctionType>();
1134 }
1135
isFunctionPointerType() const1136 bool Decl::isFunctionPointerType() const {
1137 QualType Ty;
1138 if (const auto *D = dyn_cast<ValueDecl>(this))
1139 Ty = D->getType();
1140 else if (const auto *D = dyn_cast<TypedefNameDecl>(this))
1141 Ty = D->getUnderlyingType();
1142 else
1143 return false;
1144
1145 return Ty.getCanonicalType()->isFunctionPointerType();
1146 }
1147
getNonTransparentDeclContext()1148 DeclContext *Decl::getNonTransparentDeclContext() {
1149 assert(getDeclContext());
1150 return getDeclContext()->getNonTransparentContext();
1151 }
1152
1153 /// Starting at a given context (a Decl or DeclContext), look for a
1154 /// code context that is not a closure (a lambda, block, etc.).
getNonClosureContext(T * D)1155 template <class T> static Decl *getNonClosureContext(T *D) {
1156 if (getKind(D) == Decl::CXXMethod) {
1157 auto *MD = cast<CXXMethodDecl>(D);
1158 if (MD->getOverloadedOperator() == OO_Call &&
1159 MD->getParent()->isLambda())
1160 return getNonClosureContext(MD->getParent()->getParent());
1161 return MD;
1162 }
1163 if (auto *FD = dyn_cast<FunctionDecl>(D))
1164 return FD;
1165 if (auto *MD = dyn_cast<ObjCMethodDecl>(D))
1166 return MD;
1167 if (auto *BD = dyn_cast<BlockDecl>(D))
1168 return getNonClosureContext(BD->getParent());
1169 if (auto *CD = dyn_cast<CapturedDecl>(D))
1170 return getNonClosureContext(CD->getParent());
1171 return nullptr;
1172 }
1173
getNonClosureContext()1174 Decl *Decl::getNonClosureContext() {
1175 return ::getNonClosureContext(this);
1176 }
1177
getNonClosureAncestor()1178 Decl *DeclContext::getNonClosureAncestor() {
1179 return ::getNonClosureContext(this);
1180 }
1181
1182 //===----------------------------------------------------------------------===//
1183 // DeclContext Implementation
1184 //===----------------------------------------------------------------------===//
1185
DeclContext(Decl::Kind K)1186 DeclContext::DeclContext(Decl::Kind K) {
1187 DeclContextBits.DeclKind = K;
1188 setHasExternalLexicalStorage(false);
1189 setHasExternalVisibleStorage(false);
1190 setNeedToReconcileExternalVisibleStorage(false);
1191 setHasLazyLocalLexicalLookups(false);
1192 setHasLazyExternalLexicalLookups(false);
1193 setUseQualifiedLookup(false);
1194 }
1195
classof(const Decl * D)1196 bool DeclContext::classof(const Decl *D) {
1197 Decl::Kind DK = D->getKind();
1198 switch (DK) {
1199 #define DECL(NAME, BASE)
1200 #define DECL_CONTEXT(NAME) case Decl::NAME:
1201 #include "clang/AST/DeclNodes.inc"
1202 return true;
1203 default:
1204 return false;
1205 }
1206 }
1207
1208 DeclContext::~DeclContext() = default;
1209
1210 /// Find the parent context of this context that will be
1211 /// used for unqualified name lookup.
1212 ///
1213 /// Generally, the parent lookup context is the semantic context. However, for
1214 /// a friend function the parent lookup context is the lexical context, which
1215 /// is the class in which the friend is declared.
getLookupParent()1216 DeclContext *DeclContext::getLookupParent() {
1217 // FIXME: Find a better way to identify friends.
1218 if (isa<FunctionDecl>(this))
1219 if (getParent()->getRedeclContext()->isFileContext() &&
1220 getLexicalParent()->getRedeclContext()->isRecord())
1221 return getLexicalParent();
1222
1223 // A lookup within the call operator of a lambda never looks in the lambda
1224 // class; instead, skip to the context in which that closure type is
1225 // declared.
1226 if (isLambdaCallOperator(this))
1227 return getParent()->getParent();
1228
1229 return getParent();
1230 }
1231
getInnermostBlockDecl() const1232 const BlockDecl *DeclContext::getInnermostBlockDecl() const {
1233 const DeclContext *Ctx = this;
1234
1235 do {
1236 if (Ctx->isClosure())
1237 return cast<BlockDecl>(Ctx);
1238 Ctx = Ctx->getParent();
1239 } while (Ctx);
1240
1241 return nullptr;
1242 }
1243
isInlineNamespace() const1244 bool DeclContext::isInlineNamespace() const {
1245 return isNamespace() &&
1246 cast<NamespaceDecl>(this)->isInline();
1247 }
1248
isStdNamespace() const1249 bool DeclContext::isStdNamespace() const {
1250 if (!isNamespace())
1251 return false;
1252
1253 const auto *ND = cast<NamespaceDecl>(this);
1254 if (ND->isInline()) {
1255 return ND->getParent()->isStdNamespace();
1256 }
1257
1258 if (!getParent()->getRedeclContext()->isTranslationUnit())
1259 return false;
1260
1261 const IdentifierInfo *II = ND->getIdentifier();
1262 return II && II->isStr("std");
1263 }
1264
isDependentContext() const1265 bool DeclContext::isDependentContext() const {
1266 if (isFileContext())
1267 return false;
1268
1269 if (isa<ClassTemplatePartialSpecializationDecl>(this))
1270 return true;
1271
1272 if (const auto *Record = dyn_cast<CXXRecordDecl>(this)) {
1273 if (Record->getDescribedClassTemplate())
1274 return true;
1275
1276 if (Record->isDependentLambda())
1277 return true;
1278 if (Record->isNeverDependentLambda())
1279 return false;
1280 }
1281
1282 if (const auto *Function = dyn_cast<FunctionDecl>(this)) {
1283 if (Function->getDescribedFunctionTemplate())
1284 return true;
1285
1286 // Friend function declarations are dependent if their *lexical*
1287 // context is dependent.
1288 if (cast<Decl>(this)->getFriendObjectKind())
1289 return getLexicalParent()->isDependentContext();
1290 }
1291
1292 // FIXME: A variable template is a dependent context, but is not a
1293 // DeclContext. A context within it (such as a lambda-expression)
1294 // should be considered dependent.
1295
1296 return getParent() && getParent()->isDependentContext();
1297 }
1298
isTransparentContext() const1299 bool DeclContext::isTransparentContext() const {
1300 if (getDeclKind() == Decl::Enum)
1301 return !cast<EnumDecl>(this)->isScoped();
1302
1303 return isa<LinkageSpecDecl, ExportDecl, HLSLBufferDecl>(this);
1304 }
1305
isLinkageSpecContext(const DeclContext * DC,LinkageSpecLanguageIDs ID)1306 static bool isLinkageSpecContext(const DeclContext *DC,
1307 LinkageSpecLanguageIDs ID) {
1308 while (DC->getDeclKind() != Decl::TranslationUnit) {
1309 if (DC->getDeclKind() == Decl::LinkageSpec)
1310 return cast<LinkageSpecDecl>(DC)->getLanguage() == ID;
1311 DC = DC->getLexicalParent();
1312 }
1313 return false;
1314 }
1315
isExternCContext() const1316 bool DeclContext::isExternCContext() const {
1317 return isLinkageSpecContext(this, LinkageSpecLanguageIDs::C);
1318 }
1319
getExternCContext() const1320 const LinkageSpecDecl *DeclContext::getExternCContext() const {
1321 const DeclContext *DC = this;
1322 while (DC->getDeclKind() != Decl::TranslationUnit) {
1323 if (DC->getDeclKind() == Decl::LinkageSpec &&
1324 cast<LinkageSpecDecl>(DC)->getLanguage() == LinkageSpecLanguageIDs::C)
1325 return cast<LinkageSpecDecl>(DC);
1326 DC = DC->getLexicalParent();
1327 }
1328 return nullptr;
1329 }
1330
isExternCXXContext() const1331 bool DeclContext::isExternCXXContext() const {
1332 return isLinkageSpecContext(this, LinkageSpecLanguageIDs::CXX);
1333 }
1334
Encloses(const DeclContext * DC) const1335 bool DeclContext::Encloses(const DeclContext *DC) const {
1336 if (getPrimaryContext() != this)
1337 return getPrimaryContext()->Encloses(DC);
1338
1339 for (; DC; DC = DC->getParent())
1340 if (!isa<LinkageSpecDecl>(DC) && !isa<ExportDecl>(DC) &&
1341 DC->getPrimaryContext() == this)
1342 return true;
1343 return false;
1344 }
1345
getNonTransparentContext()1346 DeclContext *DeclContext::getNonTransparentContext() {
1347 DeclContext *DC = this;
1348 while (DC->isTransparentContext()) {
1349 DC = DC->getParent();
1350 assert(DC && "All transparent contexts should have a parent!");
1351 }
1352 return DC;
1353 }
1354
getPrimaryContext()1355 DeclContext *DeclContext::getPrimaryContext() {
1356 switch (getDeclKind()) {
1357 case Decl::ExternCContext:
1358 case Decl::LinkageSpec:
1359 case Decl::Export:
1360 case Decl::Block:
1361 case Decl::Captured:
1362 case Decl::OMPDeclareReduction:
1363 case Decl::OMPDeclareMapper:
1364 case Decl::RequiresExprBody:
1365 // There is only one DeclContext for these entities.
1366 return this;
1367
1368 case Decl::HLSLBuffer:
1369 // Each buffer, even with the same name, is a distinct construct.
1370 // Multiple buffers with the same name are allowed for backward
1371 // compatibility.
1372 // As long as buffers have unique resource bindings the names don't matter.
1373 // The names get exposed via the CPU-side reflection API which
1374 // supports querying bindings, so we cannot remove them.
1375 return this;
1376
1377 case Decl::TranslationUnit:
1378 return static_cast<TranslationUnitDecl *>(this)->getFirstDecl();
1379 case Decl::Namespace:
1380 // The original namespace is our primary context.
1381 return static_cast<NamespaceDecl *>(this)->getOriginalNamespace();
1382
1383 case Decl::ObjCMethod:
1384 return this;
1385
1386 case Decl::ObjCInterface:
1387 if (auto *OID = dyn_cast<ObjCInterfaceDecl>(this))
1388 if (auto *Def = OID->getDefinition())
1389 return Def;
1390 return this;
1391
1392 case Decl::ObjCProtocol:
1393 if (auto *OPD = dyn_cast<ObjCProtocolDecl>(this))
1394 if (auto *Def = OPD->getDefinition())
1395 return Def;
1396 return this;
1397
1398 case Decl::ObjCCategory:
1399 return this;
1400
1401 case Decl::ObjCImplementation:
1402 case Decl::ObjCCategoryImpl:
1403 return this;
1404
1405 default:
1406 if (getDeclKind() >= Decl::firstTag && getDeclKind() <= Decl::lastTag) {
1407 // If this is a tag type that has a definition or is currently
1408 // being defined, that definition is our primary context.
1409 auto *Tag = cast<TagDecl>(this);
1410
1411 if (TagDecl *Def = Tag->getDefinition())
1412 return Def;
1413
1414 if (const auto *TagTy = dyn_cast<TagType>(Tag->getTypeForDecl())) {
1415 // Note, TagType::getDecl returns the (partial) definition one exists.
1416 TagDecl *PossiblePartialDef = TagTy->getDecl();
1417 if (PossiblePartialDef->isBeingDefined())
1418 return PossiblePartialDef;
1419 } else {
1420 assert(isa<InjectedClassNameType>(Tag->getTypeForDecl()));
1421 }
1422
1423 return Tag;
1424 }
1425
1426 assert(getDeclKind() >= Decl::firstFunction &&
1427 getDeclKind() <= Decl::lastFunction &&
1428 "Unknown DeclContext kind");
1429 return this;
1430 }
1431 }
1432
1433 template <typename T>
collectAllContextsImpl(T * Self,SmallVectorImpl<DeclContext * > & Contexts)1434 void collectAllContextsImpl(T *Self, SmallVectorImpl<DeclContext *> &Contexts) {
1435 for (T *D = Self->getMostRecentDecl(); D; D = D->getPreviousDecl())
1436 Contexts.push_back(D);
1437
1438 std::reverse(Contexts.begin(), Contexts.end());
1439 }
1440
collectAllContexts(SmallVectorImpl<DeclContext * > & Contexts)1441 void DeclContext::collectAllContexts(SmallVectorImpl<DeclContext *> &Contexts) {
1442 Contexts.clear();
1443
1444 Decl::Kind Kind = getDeclKind();
1445
1446 if (Kind == Decl::TranslationUnit)
1447 collectAllContextsImpl(static_cast<TranslationUnitDecl *>(this), Contexts);
1448 else if (Kind == Decl::Namespace)
1449 collectAllContextsImpl(static_cast<NamespaceDecl *>(this), Contexts);
1450 else
1451 Contexts.push_back(this);
1452 }
1453
1454 std::pair<Decl *, Decl *>
BuildDeclChain(ArrayRef<Decl * > Decls,bool FieldsAlreadyLoaded)1455 DeclContext::BuildDeclChain(ArrayRef<Decl *> Decls,
1456 bool FieldsAlreadyLoaded) {
1457 // Build up a chain of declarations via the Decl::NextInContextAndBits field.
1458 Decl *FirstNewDecl = nullptr;
1459 Decl *PrevDecl = nullptr;
1460 for (auto *D : Decls) {
1461 if (FieldsAlreadyLoaded && isa<FieldDecl>(D))
1462 continue;
1463
1464 if (PrevDecl)
1465 PrevDecl->NextInContextAndBits.setPointer(D);
1466 else
1467 FirstNewDecl = D;
1468
1469 PrevDecl = D;
1470 }
1471
1472 return std::make_pair(FirstNewDecl, PrevDecl);
1473 }
1474
1475 /// We have just acquired external visible storage, and we already have
1476 /// built a lookup map. For every name in the map, pull in the new names from
1477 /// the external storage.
reconcileExternalVisibleStorage() const1478 void DeclContext::reconcileExternalVisibleStorage() const {
1479 assert(hasNeedToReconcileExternalVisibleStorage() && LookupPtr);
1480 setNeedToReconcileExternalVisibleStorage(false);
1481
1482 for (auto &Lookup : *LookupPtr)
1483 Lookup.second.setHasExternalDecls();
1484 }
1485
1486 /// Load the declarations within this lexical storage from an
1487 /// external source.
1488 /// \return \c true if any declarations were added.
1489 bool
LoadLexicalDeclsFromExternalStorage() const1490 DeclContext::LoadLexicalDeclsFromExternalStorage() const {
1491 ExternalASTSource *Source = getParentASTContext().getExternalSource();
1492 assert(hasExternalLexicalStorage() && Source && "No external storage?");
1493
1494 // Notify that we have a DeclContext that is initializing.
1495 ExternalASTSource::Deserializing ADeclContext(Source);
1496
1497 // Load the external declarations, if any.
1498 SmallVector<Decl*, 64> Decls;
1499 setHasExternalLexicalStorage(false);
1500 Source->FindExternalLexicalDecls(this, Decls);
1501
1502 if (Decls.empty())
1503 return false;
1504
1505 // We may have already loaded just the fields of this record, in which case
1506 // we need to ignore them.
1507 bool FieldsAlreadyLoaded = false;
1508 if (const auto *RD = dyn_cast<RecordDecl>(this))
1509 FieldsAlreadyLoaded = RD->hasLoadedFieldsFromExternalStorage();
1510
1511 // Splice the newly-read declarations into the beginning of the list
1512 // of declarations.
1513 Decl *ExternalFirst, *ExternalLast;
1514 std::tie(ExternalFirst, ExternalLast) =
1515 BuildDeclChain(Decls, FieldsAlreadyLoaded);
1516 ExternalLast->NextInContextAndBits.setPointer(FirstDecl);
1517 FirstDecl = ExternalFirst;
1518 if (!LastDecl)
1519 LastDecl = ExternalLast;
1520 return true;
1521 }
1522
1523 DeclContext::lookup_result
SetNoExternalVisibleDeclsForName(const DeclContext * DC,DeclarationName Name)1524 ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
1525 DeclarationName Name) {
1526 ASTContext &Context = DC->getParentASTContext();
1527 StoredDeclsMap *Map;
1528 if (!(Map = DC->LookupPtr))
1529 Map = DC->CreateStoredDeclsMap(Context);
1530 if (DC->hasNeedToReconcileExternalVisibleStorage())
1531 DC->reconcileExternalVisibleStorage();
1532
1533 (*Map)[Name].removeExternalDecls();
1534
1535 return DeclContext::lookup_result();
1536 }
1537
1538 DeclContext::lookup_result
SetExternalVisibleDeclsForName(const DeclContext * DC,DeclarationName Name,ArrayRef<NamedDecl * > Decls)1539 ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
1540 DeclarationName Name,
1541 ArrayRef<NamedDecl*> Decls) {
1542 ASTContext &Context = DC->getParentASTContext();
1543 StoredDeclsMap *Map;
1544 if (!(Map = DC->LookupPtr))
1545 Map = DC->CreateStoredDeclsMap(Context);
1546 if (DC->hasNeedToReconcileExternalVisibleStorage())
1547 DC->reconcileExternalVisibleStorage();
1548
1549 StoredDeclsList &List = (*Map)[Name];
1550 List.replaceExternalDecls(Decls);
1551 return List.getLookupResult();
1552 }
1553
decls_begin() const1554 DeclContext::decl_iterator DeclContext::decls_begin() const {
1555 if (hasExternalLexicalStorage())
1556 LoadLexicalDeclsFromExternalStorage();
1557 return decl_iterator(FirstDecl);
1558 }
1559
decls_empty() const1560 bool DeclContext::decls_empty() const {
1561 if (hasExternalLexicalStorage())
1562 LoadLexicalDeclsFromExternalStorage();
1563
1564 return !FirstDecl;
1565 }
1566
containsDecl(Decl * D) const1567 bool DeclContext::containsDecl(Decl *D) const {
1568 return (D->getLexicalDeclContext() == this &&
1569 (D->NextInContextAndBits.getPointer() || D == LastDecl));
1570 }
1571
containsDeclAndLoad(Decl * D) const1572 bool DeclContext::containsDeclAndLoad(Decl *D) const {
1573 if (hasExternalLexicalStorage())
1574 LoadLexicalDeclsFromExternalStorage();
1575 return containsDecl(D);
1576 }
1577
1578 /// shouldBeHidden - Determine whether a declaration which was declared
1579 /// within its semantic context should be invisible to qualified name lookup.
shouldBeHidden(NamedDecl * D)1580 static bool shouldBeHidden(NamedDecl *D) {
1581 // Skip unnamed declarations.
1582 if (!D->getDeclName())
1583 return true;
1584
1585 // Skip entities that can't be found by name lookup into a particular
1586 // context.
1587 if ((D->getIdentifierNamespace() == 0 && !isa<UsingDirectiveDecl>(D)) ||
1588 D->isTemplateParameter())
1589 return true;
1590
1591 // Skip friends and local extern declarations unless they're the first
1592 // declaration of the entity.
1593 if ((D->isLocalExternDecl() || D->getFriendObjectKind()) &&
1594 D != D->getCanonicalDecl())
1595 return true;
1596
1597 // Skip template specializations.
1598 // FIXME: This feels like a hack. Should DeclarationName support
1599 // template-ids, or is there a better way to keep specializations
1600 // from being visible?
1601 if (isa<ClassTemplateSpecializationDecl>(D))
1602 return true;
1603 if (auto *FD = dyn_cast<FunctionDecl>(D))
1604 if (FD->isFunctionTemplateSpecialization())
1605 return true;
1606
1607 // Hide destructors that are invalid. There should always be one destructor,
1608 // but if it is an invalid decl, another one is created. We need to hide the
1609 // invalid one from places that expect exactly one destructor, like the
1610 // serialization code.
1611 if (isa<CXXDestructorDecl>(D) && D->isInvalidDecl())
1612 return true;
1613
1614 return false;
1615 }
1616
removeDecl(Decl * D)1617 void DeclContext::removeDecl(Decl *D) {
1618 assert(D->getLexicalDeclContext() == this &&
1619 "decl being removed from non-lexical context");
1620 assert((D->NextInContextAndBits.getPointer() || D == LastDecl) &&
1621 "decl is not in decls list");
1622
1623 // Remove D from the decl chain. This is O(n) but hopefully rare.
1624 if (D == FirstDecl) {
1625 if (D == LastDecl)
1626 FirstDecl = LastDecl = nullptr;
1627 else
1628 FirstDecl = D->NextInContextAndBits.getPointer();
1629 } else {
1630 for (Decl *I = FirstDecl; true; I = I->NextInContextAndBits.getPointer()) {
1631 assert(I && "decl not found in linked list");
1632 if (I->NextInContextAndBits.getPointer() == D) {
1633 I->NextInContextAndBits.setPointer(D->NextInContextAndBits.getPointer());
1634 if (D == LastDecl) LastDecl = I;
1635 break;
1636 }
1637 }
1638 }
1639
1640 // Mark that D is no longer in the decl chain.
1641 D->NextInContextAndBits.setPointer(nullptr);
1642
1643 // Remove D from the lookup table if necessary.
1644 if (isa<NamedDecl>(D)) {
1645 auto *ND = cast<NamedDecl>(D);
1646
1647 // Do not try to remove the declaration if that is invisible to qualified
1648 // lookup. E.g. template specializations are skipped.
1649 if (shouldBeHidden(ND))
1650 return;
1651
1652 // Remove only decls that have a name
1653 if (!ND->getDeclName())
1654 return;
1655
1656 auto *DC = D->getDeclContext();
1657 do {
1658 StoredDeclsMap *Map = DC->getPrimaryContext()->LookupPtr;
1659 if (Map) {
1660 StoredDeclsMap::iterator Pos = Map->find(ND->getDeclName());
1661 assert(Pos != Map->end() && "no lookup entry for decl");
1662 StoredDeclsList &List = Pos->second;
1663 List.remove(ND);
1664 // Clean up the entry if there are no more decls.
1665 if (List.isNull())
1666 Map->erase(Pos);
1667 }
1668 } while (DC->isTransparentContext() && (DC = DC->getParent()));
1669 }
1670 }
1671
addHiddenDecl(Decl * D)1672 void DeclContext::addHiddenDecl(Decl *D) {
1673 assert(D->getLexicalDeclContext() == this &&
1674 "Decl inserted into wrong lexical context");
1675 assert(!D->getNextDeclInContext() && D != LastDecl &&
1676 "Decl already inserted into a DeclContext");
1677
1678 if (FirstDecl) {
1679 LastDecl->NextInContextAndBits.setPointer(D);
1680 LastDecl = D;
1681 } else {
1682 FirstDecl = LastDecl = D;
1683 }
1684
1685 // Notify a C++ record declaration that we've added a member, so it can
1686 // update its class-specific state.
1687 if (auto *Record = dyn_cast<CXXRecordDecl>(this))
1688 Record->addedMember(D);
1689
1690 // If this is a newly-created (not de-serialized) import declaration, wire
1691 // it in to the list of local import declarations.
1692 if (!D->isFromASTFile()) {
1693 if (auto *Import = dyn_cast<ImportDecl>(D))
1694 D->getASTContext().addedLocalImportDecl(Import);
1695 }
1696 }
1697
addDecl(Decl * D)1698 void DeclContext::addDecl(Decl *D) {
1699 addHiddenDecl(D);
1700
1701 if (auto *ND = dyn_cast<NamedDecl>(D))
1702 ND->getDeclContext()->getPrimaryContext()->
1703 makeDeclVisibleInContextWithFlags(ND, false, true);
1704 }
1705
addDeclInternal(Decl * D)1706 void DeclContext::addDeclInternal(Decl *D) {
1707 addHiddenDecl(D);
1708
1709 if (auto *ND = dyn_cast<NamedDecl>(D))
1710 ND->getDeclContext()->getPrimaryContext()->
1711 makeDeclVisibleInContextWithFlags(ND, true, true);
1712 }
1713
1714 /// buildLookup - Build the lookup data structure with all of the
1715 /// declarations in this DeclContext (and any other contexts linked
1716 /// to it or transparent contexts nested within it) and return it.
1717 ///
1718 /// Note that the produced map may miss out declarations from an
1719 /// external source. If it does, those entries will be marked with
1720 /// the 'hasExternalDecls' flag.
buildLookup()1721 StoredDeclsMap *DeclContext::buildLookup() {
1722 assert(this == getPrimaryContext() && "buildLookup called on non-primary DC");
1723
1724 if (!hasLazyLocalLexicalLookups() &&
1725 !hasLazyExternalLexicalLookups())
1726 return LookupPtr;
1727
1728 SmallVector<DeclContext *, 2> Contexts;
1729 collectAllContexts(Contexts);
1730
1731 if (hasLazyExternalLexicalLookups()) {
1732 setHasLazyExternalLexicalLookups(false);
1733 for (auto *DC : Contexts) {
1734 if (DC->hasExternalLexicalStorage()) {
1735 bool LoadedDecls = DC->LoadLexicalDeclsFromExternalStorage();
1736 setHasLazyLocalLexicalLookups(
1737 hasLazyLocalLexicalLookups() | LoadedDecls );
1738 }
1739 }
1740
1741 if (!hasLazyLocalLexicalLookups())
1742 return LookupPtr;
1743 }
1744
1745 for (auto *DC : Contexts)
1746 buildLookupImpl(DC, hasExternalVisibleStorage());
1747
1748 // We no longer have any lazy decls.
1749 setHasLazyLocalLexicalLookups(false);
1750 return LookupPtr;
1751 }
1752
1753 /// buildLookupImpl - Build part of the lookup data structure for the
1754 /// declarations contained within DCtx, which will either be this
1755 /// DeclContext, a DeclContext linked to it, or a transparent context
1756 /// nested within it.
buildLookupImpl(DeclContext * DCtx,bool Internal)1757 void DeclContext::buildLookupImpl(DeclContext *DCtx, bool Internal) {
1758 for (auto *D : DCtx->noload_decls()) {
1759 // Insert this declaration into the lookup structure, but only if
1760 // it's semantically within its decl context. Any other decls which
1761 // should be found in this context are added eagerly.
1762 //
1763 // If it's from an AST file, don't add it now. It'll get handled by
1764 // FindExternalVisibleDeclsByName if needed. Exception: if we're not
1765 // in C++, we do not track external visible decls for the TU, so in
1766 // that case we need to collect them all here.
1767 if (auto *ND = dyn_cast<NamedDecl>(D))
1768 if (ND->getDeclContext() == DCtx && !shouldBeHidden(ND) &&
1769 (!ND->isFromASTFile() ||
1770 (isTranslationUnit() &&
1771 !getParentASTContext().getLangOpts().CPlusPlus)))
1772 makeDeclVisibleInContextImpl(ND, Internal);
1773
1774 // If this declaration is itself a transparent declaration context
1775 // or inline namespace, add the members of this declaration of that
1776 // context (recursively).
1777 if (auto *InnerCtx = dyn_cast<DeclContext>(D))
1778 if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
1779 buildLookupImpl(InnerCtx, Internal);
1780 }
1781 }
1782
1783 DeclContext::lookup_result
lookup(DeclarationName Name) const1784 DeclContext::lookup(DeclarationName Name) const {
1785 // For transparent DeclContext, we should lookup in their enclosing context.
1786 if (getDeclKind() == Decl::LinkageSpec || getDeclKind() == Decl::Export)
1787 return getParent()->lookup(Name);
1788
1789 const DeclContext *PrimaryContext = getPrimaryContext();
1790 if (PrimaryContext != this)
1791 return PrimaryContext->lookup(Name);
1792
1793 // If we have an external source, ensure that any later redeclarations of this
1794 // context have been loaded, since they may add names to the result of this
1795 // lookup (or add external visible storage).
1796 ExternalASTSource *Source = getParentASTContext().getExternalSource();
1797 if (Source)
1798 (void)cast<Decl>(this)->getMostRecentDecl();
1799
1800 if (hasExternalVisibleStorage()) {
1801 assert(Source && "external visible storage but no external source?");
1802
1803 if (hasNeedToReconcileExternalVisibleStorage())
1804 reconcileExternalVisibleStorage();
1805
1806 StoredDeclsMap *Map = LookupPtr;
1807
1808 if (hasLazyLocalLexicalLookups() ||
1809 hasLazyExternalLexicalLookups())
1810 // FIXME: Make buildLookup const?
1811 Map = const_cast<DeclContext*>(this)->buildLookup();
1812
1813 if (!Map)
1814 Map = CreateStoredDeclsMap(getParentASTContext());
1815
1816 // If we have a lookup result with no external decls, we are done.
1817 std::pair<StoredDeclsMap::iterator, bool> R =
1818 Map->insert(std::make_pair(Name, StoredDeclsList()));
1819 if (!R.second && !R.first->second.hasExternalDecls())
1820 return R.first->second.getLookupResult();
1821
1822 if (Source->FindExternalVisibleDeclsByName(this, Name) || !R.second) {
1823 if (StoredDeclsMap *Map = LookupPtr) {
1824 StoredDeclsMap::iterator I = Map->find(Name);
1825 if (I != Map->end())
1826 return I->second.getLookupResult();
1827 }
1828 }
1829
1830 return {};
1831 }
1832
1833 StoredDeclsMap *Map = LookupPtr;
1834 if (hasLazyLocalLexicalLookups() ||
1835 hasLazyExternalLexicalLookups())
1836 Map = const_cast<DeclContext*>(this)->buildLookup();
1837
1838 if (!Map)
1839 return {};
1840
1841 StoredDeclsMap::iterator I = Map->find(Name);
1842 if (I == Map->end())
1843 return {};
1844
1845 return I->second.getLookupResult();
1846 }
1847
1848 DeclContext::lookup_result
noload_lookup(DeclarationName Name)1849 DeclContext::noload_lookup(DeclarationName Name) {
1850 assert(getDeclKind() != Decl::LinkageSpec &&
1851 getDeclKind() != Decl::Export &&
1852 "should not perform lookups into transparent contexts");
1853
1854 DeclContext *PrimaryContext = getPrimaryContext();
1855 if (PrimaryContext != this)
1856 return PrimaryContext->noload_lookup(Name);
1857
1858 loadLazyLocalLexicalLookups();
1859 StoredDeclsMap *Map = LookupPtr;
1860 if (!Map)
1861 return {};
1862
1863 StoredDeclsMap::iterator I = Map->find(Name);
1864 return I != Map->end() ? I->second.getLookupResult()
1865 : lookup_result();
1866 }
1867
1868 // If we have any lazy lexical declarations not in our lookup map, add them
1869 // now. Don't import any external declarations, not even if we know we have
1870 // some missing from the external visible lookups.
loadLazyLocalLexicalLookups()1871 void DeclContext::loadLazyLocalLexicalLookups() {
1872 if (hasLazyLocalLexicalLookups()) {
1873 SmallVector<DeclContext *, 2> Contexts;
1874 collectAllContexts(Contexts);
1875 for (auto *Context : Contexts)
1876 buildLookupImpl(Context, hasExternalVisibleStorage());
1877 setHasLazyLocalLexicalLookups(false);
1878 }
1879 }
1880
localUncachedLookup(DeclarationName Name,SmallVectorImpl<NamedDecl * > & Results)1881 void DeclContext::localUncachedLookup(DeclarationName Name,
1882 SmallVectorImpl<NamedDecl *> &Results) {
1883 Results.clear();
1884
1885 // If there's no external storage, just perform a normal lookup and copy
1886 // the results.
1887 if (!hasExternalVisibleStorage() && !hasExternalLexicalStorage() && Name) {
1888 lookup_result LookupResults = lookup(Name);
1889 Results.insert(Results.end(), LookupResults.begin(), LookupResults.end());
1890 if (!Results.empty())
1891 return;
1892 }
1893
1894 // If we have a lookup table, check there first. Maybe we'll get lucky.
1895 // FIXME: Should we be checking these flags on the primary context?
1896 if (Name && !hasLazyLocalLexicalLookups() &&
1897 !hasLazyExternalLexicalLookups()) {
1898 if (StoredDeclsMap *Map = LookupPtr) {
1899 StoredDeclsMap::iterator Pos = Map->find(Name);
1900 if (Pos != Map->end()) {
1901 Results.insert(Results.end(),
1902 Pos->second.getLookupResult().begin(),
1903 Pos->second.getLookupResult().end());
1904 return;
1905 }
1906 }
1907 }
1908
1909 // Slow case: grovel through the declarations in our chain looking for
1910 // matches.
1911 // FIXME: If we have lazy external declarations, this will not find them!
1912 // FIXME: Should we CollectAllContexts and walk them all here?
1913 for (Decl *D = FirstDecl; D; D = D->getNextDeclInContext()) {
1914 if (auto *ND = dyn_cast<NamedDecl>(D))
1915 if (ND->getDeclName() == Name)
1916 Results.push_back(ND);
1917 }
1918 }
1919
getRedeclContext()1920 DeclContext *DeclContext::getRedeclContext() {
1921 DeclContext *Ctx = this;
1922
1923 // In C, a record type is the redeclaration context for its fields only. If
1924 // we arrive at a record context after skipping anything else, we should skip
1925 // the record as well. Currently, this means skipping enumerations because
1926 // they're the only transparent context that can exist within a struct or
1927 // union.
1928 bool SkipRecords = getDeclKind() == Decl::Kind::Enum &&
1929 !getParentASTContext().getLangOpts().CPlusPlus;
1930
1931 // Skip through contexts to get to the redeclaration context. Transparent
1932 // contexts are always skipped.
1933 while ((SkipRecords && Ctx->isRecord()) || Ctx->isTransparentContext())
1934 Ctx = Ctx->getParent();
1935 return Ctx;
1936 }
1937
getEnclosingNamespaceContext()1938 DeclContext *DeclContext::getEnclosingNamespaceContext() {
1939 DeclContext *Ctx = this;
1940 // Skip through non-namespace, non-translation-unit contexts.
1941 while (!Ctx->isFileContext())
1942 Ctx = Ctx->getParent();
1943 return Ctx->getPrimaryContext();
1944 }
1945
getOuterLexicalRecordContext()1946 RecordDecl *DeclContext::getOuterLexicalRecordContext() {
1947 // Loop until we find a non-record context.
1948 RecordDecl *OutermostRD = nullptr;
1949 DeclContext *DC = this;
1950 while (DC->isRecord()) {
1951 OutermostRD = cast<RecordDecl>(DC);
1952 DC = DC->getLexicalParent();
1953 }
1954 return OutermostRD;
1955 }
1956
InEnclosingNamespaceSetOf(const DeclContext * O) const1957 bool DeclContext::InEnclosingNamespaceSetOf(const DeclContext *O) const {
1958 // For non-file contexts, this is equivalent to Equals.
1959 if (!isFileContext())
1960 return O->Equals(this);
1961
1962 do {
1963 if (O->Equals(this))
1964 return true;
1965
1966 const auto *NS = dyn_cast<NamespaceDecl>(O);
1967 if (!NS || !NS->isInline())
1968 break;
1969 O = NS->getParent();
1970 } while (O);
1971
1972 return false;
1973 }
1974
makeDeclVisibleInContext(NamedDecl * D)1975 void DeclContext::makeDeclVisibleInContext(NamedDecl *D) {
1976 DeclContext *PrimaryDC = this->getPrimaryContext();
1977 DeclContext *DeclDC = D->getDeclContext()->getPrimaryContext();
1978 // If the decl is being added outside of its semantic decl context, we
1979 // need to ensure that we eagerly build the lookup information for it.
1980 PrimaryDC->makeDeclVisibleInContextWithFlags(D, false, PrimaryDC == DeclDC);
1981 }
1982
makeDeclVisibleInContextWithFlags(NamedDecl * D,bool Internal,bool Recoverable)1983 void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
1984 bool Recoverable) {
1985 assert(this == getPrimaryContext() && "expected a primary DC");
1986
1987 if (!isLookupContext()) {
1988 if (isTransparentContext())
1989 getParent()->getPrimaryContext()
1990 ->makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
1991 return;
1992 }
1993
1994 // Skip declarations which should be invisible to name lookup.
1995 if (shouldBeHidden(D))
1996 return;
1997
1998 // If we already have a lookup data structure, perform the insertion into
1999 // it. If we might have externally-stored decls with this name, look them
2000 // up and perform the insertion. If this decl was declared outside its
2001 // semantic context, buildLookup won't add it, so add it now.
2002 //
2003 // FIXME: As a performance hack, don't add such decls into the translation
2004 // unit unless we're in C++, since qualified lookup into the TU is never
2005 // performed.
2006 if (LookupPtr || hasExternalVisibleStorage() ||
2007 ((!Recoverable || D->getDeclContext() != D->getLexicalDeclContext()) &&
2008 (getParentASTContext().getLangOpts().CPlusPlus ||
2009 !isTranslationUnit()))) {
2010 // If we have lazily omitted any decls, they might have the same name as
2011 // the decl which we are adding, so build a full lookup table before adding
2012 // this decl.
2013 buildLookup();
2014 makeDeclVisibleInContextImpl(D, Internal);
2015 } else {
2016 setHasLazyLocalLexicalLookups(true);
2017 }
2018
2019 // If we are a transparent context or inline namespace, insert into our
2020 // parent context, too. This operation is recursive.
2021 if (isTransparentContext() || isInlineNamespace())
2022 getParent()->getPrimaryContext()->
2023 makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
2024
2025 auto *DCAsDecl = cast<Decl>(this);
2026 // Notify that a decl was made visible unless we are a Tag being defined.
2027 if (!(isa<TagDecl>(DCAsDecl) && cast<TagDecl>(DCAsDecl)->isBeingDefined()))
2028 if (ASTMutationListener *L = DCAsDecl->getASTMutationListener())
2029 L->AddedVisibleDecl(this, D);
2030 }
2031
makeDeclVisibleInContextImpl(NamedDecl * D,bool Internal)2032 void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
2033 // Find or create the stored declaration map.
2034 StoredDeclsMap *Map = LookupPtr;
2035 if (!Map) {
2036 ASTContext *C = &getParentASTContext();
2037 Map = CreateStoredDeclsMap(*C);
2038 }
2039
2040 // If there is an external AST source, load any declarations it knows about
2041 // with this declaration's name.
2042 // If the lookup table contains an entry about this name it means that we
2043 // have already checked the external source.
2044 if (!Internal)
2045 if (ExternalASTSource *Source = getParentASTContext().getExternalSource())
2046 if (hasExternalVisibleStorage() &&
2047 Map->find(D->getDeclName()) == Map->end())
2048 Source->FindExternalVisibleDeclsByName(this, D->getDeclName());
2049
2050 // Insert this declaration into the map.
2051 StoredDeclsList &DeclNameEntries = (*Map)[D->getDeclName()];
2052
2053 if (Internal) {
2054 // If this is being added as part of loading an external declaration,
2055 // this may not be the only external declaration with this name.
2056 // In this case, we never try to replace an existing declaration; we'll
2057 // handle that when we finalize the list of declarations for this name.
2058 DeclNameEntries.setHasExternalDecls();
2059 DeclNameEntries.prependDeclNoReplace(D);
2060 return;
2061 }
2062
2063 DeclNameEntries.addOrReplaceDecl(D);
2064 }
2065
operator *() const2066 UsingDirectiveDecl *DeclContext::udir_iterator::operator*() const {
2067 return cast<UsingDirectiveDecl>(*I);
2068 }
2069
2070 /// Returns iterator range [First, Last) of UsingDirectiveDecls stored within
2071 /// this context.
using_directives() const2072 DeclContext::udir_range DeclContext::using_directives() const {
2073 // FIXME: Use something more efficient than normal lookup for using
2074 // directives. In C++, using directives are looked up more than anything else.
2075 lookup_result Result = lookup(UsingDirectiveDecl::getName());
2076 return udir_range(Result.begin(), Result.end());
2077 }
2078
2079 //===----------------------------------------------------------------------===//
2080 // Creation and Destruction of StoredDeclsMaps. //
2081 //===----------------------------------------------------------------------===//
2082
CreateStoredDeclsMap(ASTContext & C) const2083 StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
2084 assert(!LookupPtr && "context already has a decls map");
2085 assert(getPrimaryContext() == this &&
2086 "creating decls map on non-primary context");
2087
2088 StoredDeclsMap *M;
2089 bool Dependent = isDependentContext();
2090 if (Dependent)
2091 M = new DependentStoredDeclsMap();
2092 else
2093 M = new StoredDeclsMap();
2094 M->Previous = C.LastSDM;
2095 C.LastSDM = llvm::PointerIntPair<StoredDeclsMap*,1>(M, Dependent);
2096 LookupPtr = M;
2097 return M;
2098 }
2099
ReleaseDeclContextMaps()2100 void ASTContext::ReleaseDeclContextMaps() {
2101 // It's okay to delete DependentStoredDeclsMaps via a StoredDeclsMap
2102 // pointer because the subclass doesn't add anything that needs to
2103 // be deleted.
2104 StoredDeclsMap::DestroyAll(LastSDM.getPointer(), LastSDM.getInt());
2105 LastSDM.setPointer(nullptr);
2106 }
2107
DestroyAll(StoredDeclsMap * Map,bool Dependent)2108 void StoredDeclsMap::DestroyAll(StoredDeclsMap *Map, bool Dependent) {
2109 while (Map) {
2110 // Advance the iteration before we invalidate memory.
2111 llvm::PointerIntPair<StoredDeclsMap*,1> Next = Map->Previous;
2112
2113 if (Dependent)
2114 delete static_cast<DependentStoredDeclsMap*>(Map);
2115 else
2116 delete Map;
2117
2118 Map = Next.getPointer();
2119 Dependent = Next.getInt();
2120 }
2121 }
2122
Create(ASTContext & C,DeclContext * Parent,const PartialDiagnostic & PDiag)2123 DependentDiagnostic *DependentDiagnostic::Create(ASTContext &C,
2124 DeclContext *Parent,
2125 const PartialDiagnostic &PDiag) {
2126 assert(Parent->isDependentContext()
2127 && "cannot iterate dependent diagnostics of non-dependent context");
2128 Parent = Parent->getPrimaryContext();
2129 if (!Parent->LookupPtr)
2130 Parent->CreateStoredDeclsMap(C);
2131
2132 auto *Map = static_cast<DependentStoredDeclsMap *>(Parent->LookupPtr);
2133
2134 // Allocate the copy of the PartialDiagnostic via the ASTContext's
2135 // BumpPtrAllocator, rather than the ASTContext itself.
2136 DiagnosticStorage *DiagStorage = nullptr;
2137 if (PDiag.hasStorage())
2138 DiagStorage = new (C) DiagnosticStorage;
2139
2140 auto *DD = new (C) DependentDiagnostic(PDiag, DiagStorage);
2141
2142 // TODO: Maybe we shouldn't reverse the order during insertion.
2143 DD->NextDiagnostic = Map->FirstDiagnostic;
2144 Map->FirstDiagnostic = DD;
2145
2146 return DD;
2147 }
2148