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/DeclOpenACC.h"
25#include "clang/AST/DeclOpenMP.h"
26#include "clang/AST/DeclTemplate.h"
27#include "clang/AST/DependentDiagnostic.h"
28#include "clang/AST/ExternalASTSource.h"
29#include "clang/AST/Stmt.h"
30#include "clang/AST/Type.h"
31#include "clang/Basic/IdentifierTable.h"
32#include "clang/Basic/LLVM.h"
33#include "clang/Basic/Module.h"
34#include "clang/Basic/ObjCRuntime.h"
35#include "clang/Basic/PartialDiagnostic.h"
36#include "clang/Basic/SourceLocation.h"
37#include "clang/Basic/TargetInfo.h"
38#include "llvm/ADT/PointerIntPair.h"
39#include "llvm/ADT/StringRef.h"
40#include "llvm/Support/ErrorHandling.h"
41#include "llvm/Support/MathExtras.h"
42#include "llvm/Support/VersionTuple.h"
43#include "llvm/Support/raw_ostream.h"
44#include <algorithm>
45#include <cassert>
46#include <cstddef>
47#include <string>
48#include <tuple>
49#include <utility>
50
51using namespace clang;
52
53//===----------------------------------------------------------------------===//
54// Statistics
55//===----------------------------------------------------------------------===//
56
57#define DECL(DERIVED, BASE) static int n##DERIVED##s = 0;
58#define ABSTRACT_DECL(DECL)
59#include "clang/AST/DeclNodes.inc"
60
61#define DECL(DERIVED, BASE) \
62 static_assert(alignof(Decl) >= alignof(DERIVED##Decl), \
63 "Alignment sufficient after objects prepended to " #DERIVED);
64#define ABSTRACT_DECL(DECL)
65#include "clang/AST/DeclNodes.inc"
66
67void *Decl::operator new(std::size_t Size, const ASTContext &Context,
68 GlobalDeclID ID, std::size_t Extra) {
69 // Allocate an extra 8 bytes worth of storage, which ensures that the
70 // resulting pointer will still be 8-byte aligned.
71 static_assert(sizeof(uint64_t) >= alignof(Decl), "Decl won't be misaligned");
72 void *Start = Context.Allocate(Size: Size + Extra + 8);
73 void *Result = (char*)Start + 8;
74
75 uint64_t *PrefixPtr = (uint64_t *)Result - 1;
76
77 *PrefixPtr = ID.getRawValue();
78
79 // We leave the upper 16 bits to store the module IDs. 48 bits should be
80 // sufficient to store a declaration ID. See the comments in setOwningModuleID
81 // for details.
82 assert((*PrefixPtr < llvm::maskTrailingOnes<uint64_t>(48)) &&
83 "Current Implementation limits the number of module files to not "
84 "exceed 2^16. Contact Clang Developers to remove the limitation.");
85
86 return Result;
87}
88
89void *Decl::operator new(std::size_t Size, const ASTContext &Ctx,
90 DeclContext *Parent, std::size_t Extra) {
91 assert(!Parent || &Parent->getParentASTContext() == &Ctx);
92 // With local visibility enabled, we track the owning module even for local
93 // declarations. We create the TU decl early and may not yet know what the
94 // LangOpts are, so conservatively allocate the storage.
95 if (Ctx.getLangOpts().trackLocalOwningModule() || !Parent) {
96 // Ensure required alignment of the resulting object by adding extra
97 // padding at the start if required.
98 size_t ExtraAlign =
99 llvm::offsetToAlignment(Value: sizeof(Module *), Alignment: llvm::Align(alignof(Decl)));
100 auto *Buffer = reinterpret_cast<char *>(
101 ::operator new(Bytes: ExtraAlign + sizeof(Module *) + Size + Extra, C: Ctx));
102 Buffer += ExtraAlign;
103 auto *ParentModule =
104 Parent ? cast<Decl>(Val: Parent)->getOwningModule() : nullptr;
105 return new (Buffer) Module*(ParentModule) + 1;
106 }
107 return ::operator new(Bytes: Size + Extra, C: Ctx);
108}
109
110GlobalDeclID Decl::getGlobalID() const {
111 if (!isFromASTFile())
112 return GlobalDeclID();
113 // See the comments in `Decl::operator new` for details.
114 uint64_t ID = *((const uint64_t *)this - 1);
115 return GlobalDeclID(ID & llvm::maskTrailingOnes<uint64_t>(N: 48));
116}
117
118unsigned Decl::getOwningModuleID() const {
119 if (!isFromASTFile())
120 return 0;
121
122 uint64_t ID = *((const uint64_t *)this - 1);
123 return ID >> 48;
124}
125
126void Decl::setOwningModuleID(unsigned ID) {
127 assert(isFromASTFile() && "Only works on a deserialized declaration");
128 // Currently, we use 64 bits to store the GlobalDeclID and the module ID
129 // to save the space. See `Decl::operator new` for details. To make it,
130 // we split the higher 32 bits to 2 16bits for the module file index of
131 // GlobalDeclID and the module ID. This introduces a limitation that the
132 // number of modules can't exceed 2^16. (The number of module files should be
133 // less than the number of modules).
134 //
135 // It is counter-intuitive to store both the module file index and the
136 // module ID as it seems redundant. However, this is not true.
137 // The module ID may be different from the module file where it is serialized
138 // from for implicit template instantiations. See
139 // https://github.com/llvm/llvm-project/issues/101939
140 //
141 // If we reach the limitation, we have to remove the limitation by asking
142 // every deserialized declaration to pay for yet another 32 bits, or we have
143 // to review the above issue to decide what we should do for it.
144 assert((ID < llvm::maskTrailingOnes<unsigned>(16)) &&
145 "Current Implementation limits the number of modules to not exceed "
146 "2^16. Contact Clang Developers to remove the limitation.");
147 uint64_t *IDAddress = (uint64_t *)this - 1;
148 *IDAddress &= llvm::maskTrailingOnes<uint64_t>(N: 48);
149 *IDAddress |= (uint64_t)ID << 48;
150}
151
152Module *Decl::getTopLevelOwningNamedModule() const {
153 if (getOwningModule() &&
154 getOwningModule()->getTopLevelModule()->isNamedModule())
155 return getOwningModule()->getTopLevelModule();
156
157 return nullptr;
158}
159
160Module *Decl::getOwningModuleSlow() const {
161 assert(isFromASTFile() && "Not from AST file?");
162 return getASTContext().getExternalSource()->getModule(ID: getOwningModuleID());
163}
164
165bool Decl::hasLocalOwningModuleStorage() const {
166 return getASTContext().getLangOpts().trackLocalOwningModule();
167}
168
169const char *Decl::getDeclKindName() const {
170 switch (DeclKind) {
171 default: llvm_unreachable("Declaration not in DeclNodes.inc!");
172#define DECL(DERIVED, BASE) case DERIVED: return #DERIVED;
173#define ABSTRACT_DECL(DECL)
174#include "clang/AST/DeclNodes.inc"
175 }
176}
177
178void Decl::setInvalidDecl(bool Invalid) {
179 InvalidDecl = Invalid;
180 assert(!isa<TagDecl>(this) || !cast<TagDecl>(this)->isCompleteDefinition());
181 if (!Invalid) {
182 return;
183 }
184
185 if (!isa<ParmVarDecl>(Val: this)) {
186 // Defensive maneuver for ill-formed code: we're likely not to make it to
187 // a point where we set the access specifier, so default it to "public"
188 // to avoid triggering asserts elsewhere in the front end.
189 setAccess(AS_public);
190 }
191
192 // Marking a DecompositionDecl as invalid implies all the child BindingDecl's
193 // are invalid too.
194 if (auto *DD = dyn_cast<DecompositionDecl>(Val: this)) {
195 for (auto *Binding : DD->bindings()) {
196 Binding->setInvalidDecl();
197 }
198 }
199}
200
201bool DeclContext::hasValidDeclKind() const {
202 switch (getDeclKind()) {
203#define DECL(DERIVED, BASE) case Decl::DERIVED: return true;
204#define ABSTRACT_DECL(DECL)
205#include "clang/AST/DeclNodes.inc"
206 }
207 return false;
208}
209
210const char *DeclContext::getDeclKindName() const {
211 switch (getDeclKind()) {
212#define DECL(DERIVED, BASE) case Decl::DERIVED: return #DERIVED;
213#define ABSTRACT_DECL(DECL)
214#include "clang/AST/DeclNodes.inc"
215 }
216 llvm_unreachable("Declaration context not in DeclNodes.inc!");
217}
218
219bool Decl::StatisticsEnabled = false;
220void Decl::EnableStatistics() {
221 StatisticsEnabled = true;
222}
223
224void Decl::PrintStats() {
225 llvm::errs() << "\n*** Decl Stats:\n";
226
227 int totalDecls = 0;
228#define DECL(DERIVED, BASE) totalDecls += n##DERIVED##s;
229#define ABSTRACT_DECL(DECL)
230#include "clang/AST/DeclNodes.inc"
231 llvm::errs() << " " << totalDecls << " decls total.\n";
232
233 int totalBytes = 0;
234#define DECL(DERIVED, BASE) \
235 if (n##DERIVED##s > 0) { \
236 totalBytes += (int)(n##DERIVED##s * sizeof(DERIVED##Decl)); \
237 llvm::errs() << " " << n##DERIVED##s << " " #DERIVED " decls, " \
238 << sizeof(DERIVED##Decl) << " each (" \
239 << n##DERIVED##s * sizeof(DERIVED##Decl) \
240 << " bytes)\n"; \
241 }
242#define ABSTRACT_DECL(DECL)
243#include "clang/AST/DeclNodes.inc"
244
245 llvm::errs() << "Total bytes = " << totalBytes << "\n";
246}
247
248void Decl::add(Kind k) {
249 switch (k) {
250#define DECL(DERIVED, BASE) case DERIVED: ++n##DERIVED##s; break;
251#define ABSTRACT_DECL(DECL)
252#include "clang/AST/DeclNodes.inc"
253 }
254}
255
256bool Decl::isTemplateParameterPack() const {
257 if (const auto *TTP = dyn_cast<TemplateTypeParmDecl>(Val: this))
258 return TTP->isParameterPack();
259 if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Val: this))
260 return NTTP->isParameterPack();
261 if (const auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Val: this))
262 return TTP->isParameterPack();
263 return false;
264}
265
266bool Decl::isParameterPack() const {
267 if (const auto *Var = dyn_cast<ValueDecl>(Val: this))
268 return Var->isParameterPack();
269
270 return isTemplateParameterPack();
271}
272
273FunctionDecl *Decl::getAsFunction() {
274 if (auto *FD = dyn_cast<FunctionDecl>(Val: this))
275 return FD;
276 if (const auto *FTD = dyn_cast<FunctionTemplateDecl>(Val: this))
277 return FTD->getTemplatedDecl();
278 return nullptr;
279}
280
281bool Decl::isTemplateDecl() const {
282 return isa<TemplateDecl>(Val: this);
283}
284
285TemplateDecl *Decl::getDescribedTemplate() const {
286 if (auto *FD = dyn_cast<FunctionDecl>(Val: this))
287 return FD->getDescribedFunctionTemplate();
288 if (auto *RD = dyn_cast<CXXRecordDecl>(Val: this))
289 return RD->getDescribedClassTemplate();
290 if (auto *VD = dyn_cast<VarDecl>(Val: this))
291 return VD->getDescribedVarTemplate();
292 if (auto *AD = dyn_cast<TypeAliasDecl>(Val: this))
293 return AD->getDescribedAliasTemplate();
294
295 return nullptr;
296}
297
298const TemplateParameterList *Decl::getDescribedTemplateParams() const {
299 if (auto *TD = getDescribedTemplate())
300 return TD->getTemplateParameters();
301 if (auto *CTPSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(Val: this))
302 return CTPSD->getTemplateParameters();
303 if (auto *VTPSD = dyn_cast<VarTemplatePartialSpecializationDecl>(Val: this))
304 return VTPSD->getTemplateParameters();
305 return nullptr;
306}
307
308bool Decl::isTemplated() const {
309 // A declaration is templated if it is a template or a template pattern, or
310 // is within (lexcially for a friend or local function declaration,
311 // semantically otherwise) a dependent context.
312 if (auto *AsDC = dyn_cast<DeclContext>(Val: this))
313 return AsDC->isDependentContext();
314 auto *DC = getFriendObjectKind() || isLocalExternDecl()
315 ? getLexicalDeclContext() : getDeclContext();
316 return DC->isDependentContext() || isTemplateDecl() ||
317 getDescribedTemplateParams();
318}
319
320unsigned Decl::getTemplateDepth() const {
321 if (auto *DC = dyn_cast<DeclContext>(Val: this))
322 if (DC->isFileContext())
323 return 0;
324
325 if (auto *TPL = getDescribedTemplateParams())
326 return TPL->getDepth() + 1;
327
328 if (auto *ESD = dyn_cast<CXXExpansionStmtDecl>(Val: this))
329 return ESD->getIndexTemplateParm()->getDepth() + 1;
330
331 // If this is a dependent lambda, there might be an enclosing variable
332 // template. In this case, the next step is not the parent DeclContext (or
333 // even a DeclContext at all).
334 auto *RD = dyn_cast<CXXRecordDecl>(Val: this);
335 if (RD && RD->isDependentLambda())
336 if (Decl *Context = RD->getLambdaContextDecl())
337 return Context->getTemplateDepth();
338
339 const DeclContext *DC =
340 getFriendObjectKind() ? getLexicalDeclContext() : getDeclContext();
341 return cast<Decl>(Val: DC)->getTemplateDepth();
342}
343
344const DeclContext *Decl::getParentFunctionOrMethod(bool LexicalParent) const {
345 for (const DeclContext *DC = LexicalParent ? getLexicalDeclContext()
346 : getDeclContext();
347 DC && !DC->isFileContext(); DC = DC->getParent())
348 if (DC->isFunctionOrMethod())
349 return DC;
350
351 return nullptr;
352}
353
354//===----------------------------------------------------------------------===//
355// PrettyStackTraceDecl Implementation
356//===----------------------------------------------------------------------===//
357
358void PrettyStackTraceDecl::print(raw_ostream &OS) const {
359 SourceLocation TheLoc = Loc;
360 if (TheLoc.isInvalid() && TheDecl)
361 TheLoc = TheDecl->getLocation();
362
363 if (TheLoc.isValid()) {
364 TheLoc.print(OS, SM);
365 OS << ": ";
366 }
367
368 OS << Message;
369
370 if (const auto *DN = dyn_cast_or_null<NamedDecl>(Val: TheDecl)) {
371 OS << " '";
372 DN->printQualifiedName(OS);
373 OS << '\'';
374 }
375 OS << '\n';
376}
377
378//===----------------------------------------------------------------------===//
379// Decl Implementation
380//===----------------------------------------------------------------------===//
381
382// Out-of-line virtual method providing a home for Decl.
383Decl::~Decl() = default;
384
385void Decl::setDeclContext(DeclContext *DC) {
386 DeclCtx = DC;
387}
388
389void Decl::setLexicalDeclContext(DeclContext *DC) {
390 if (DC == getLexicalDeclContext())
391 return;
392
393 if (isInSemaDC()) {
394 setDeclContextsImpl(SemaDC: getDeclContext(), LexicalDC: DC, Ctx&: getASTContext());
395 } else {
396 getMultipleDC()->LexicalDC = DC;
397 }
398
399 // FIXME: We shouldn't be changing the lexical context of declarations
400 // imported from AST files.
401 if (!isFromASTFile()) {
402 setModuleOwnershipKind(getModuleOwnershipKindForChildOf(DC));
403 if (hasOwningModule())
404 setLocalOwningModule(cast<Decl>(Val: DC)->getOwningModule());
405 }
406
407 assert(
408 ((getModuleOwnershipKind() != ModuleOwnershipKind::VisibleWhenImported &&
409 getModuleOwnershipKind() != ModuleOwnershipKind::VisiblePromoted) ||
410 getOwningModule()) &&
411 "hidden declaration has no owning module");
412}
413
414void Decl::setDeclContextsImpl(DeclContext *SemaDC, DeclContext *LexicalDC,
415 ASTContext &Ctx) {
416 if (SemaDC == LexicalDC) {
417 DeclCtx = SemaDC;
418 } else {
419 auto *MDC = new (Ctx) Decl::MultipleDC();
420 MDC->SemanticDC = SemaDC;
421 MDC->LexicalDC = LexicalDC;
422 DeclCtx = MDC;
423 }
424}
425
426bool Decl::isInLocalScopeForInstantiation() const {
427 const DeclContext *LDC = getLexicalDeclContext();
428 if (!LDC->isDependentContext())
429 return false;
430 while (true) {
431 if (LDC->isFunctionOrMethod())
432 return true;
433 if (!isa<TagDecl>(Val: LDC))
434 return false;
435 if (const auto *CRD = dyn_cast<CXXRecordDecl>(Val: LDC))
436 if (CRD->isLambda())
437 return true;
438 LDC = LDC->getLexicalParent();
439 }
440 return false;
441}
442
443bool Decl::isInAnonymousNamespace() const {
444 for (const DeclContext *DC = getDeclContext(); DC; DC = DC->getParent()) {
445 if (const auto *ND = dyn_cast<NamespaceDecl>(Val: DC))
446 if (ND->isAnonymousNamespace())
447 return true;
448 }
449
450 return false;
451}
452
453bool Decl::isInStdNamespace() const {
454 const DeclContext *DC = getDeclContext();
455 return DC && DC->getNonTransparentContext()->isStdNamespace();
456}
457
458bool Decl::isFileContextDecl() const {
459 const auto *DC = dyn_cast<DeclContext>(Val: this);
460 return DC && DC->isFileContext();
461}
462
463bool Decl::isFlexibleArrayMemberLike(
464 const ASTContext &Ctx, const Decl *D, QualType Ty,
465 LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel,
466 bool IgnoreTemplateOrMacroSubstitution) {
467 // For compatibility with existing code, we treat arrays of length 0 or
468 // 1 as flexible array members.
469 const auto *CAT = Ctx.getAsConstantArrayType(T: Ty);
470 if (CAT) {
471 using FAMKind = LangOptions::StrictFlexArraysLevelKind;
472
473 llvm::APInt Size = CAT->getSize();
474 if (StrictFlexArraysLevel == FAMKind::IncompleteOnly)
475 return false;
476
477 // GCC extension, only allowed to represent a FAM.
478 if (Size.isZero())
479 return true;
480
481 if (StrictFlexArraysLevel == FAMKind::ZeroOrIncomplete && Size.uge(RHS: 1))
482 return false;
483
484 if (StrictFlexArraysLevel == FAMKind::OneZeroOrIncomplete && Size.uge(RHS: 2))
485 return false;
486 } else if (!Ctx.getAsIncompleteArrayType(T: Ty)) {
487 return false;
488 }
489
490 if (const auto *OID = dyn_cast_if_present<ObjCIvarDecl>(Val: D))
491 return OID->getNextIvar() == nullptr;
492
493 const auto *FD = dyn_cast_if_present<FieldDecl>(Val: D);
494 if (!FD)
495 return false;
496
497 if (CAT) {
498 // GCC treats an array memeber of a union as an FAM if the size is one or
499 // zero.
500 llvm::APInt Size = CAT->getSize();
501 if (FD->getParent()->isUnion() && (Size.isZero() || Size.isOne()))
502 return true;
503 }
504
505 // Don't consider sizes resulting from macro expansions or template argument
506 // substitution to form C89 tail-padded arrays.
507 if (IgnoreTemplateOrMacroSubstitution) {
508 TypeSourceInfo *TInfo = FD->getTypeSourceInfo();
509 while (TInfo) {
510 TypeLoc TL = TInfo->getTypeLoc();
511
512 // Look through typedefs.
513 if (TypedefTypeLoc TTL = TL.getAsAdjusted<TypedefTypeLoc>()) {
514 TInfo = TTL.getDecl()->getTypeSourceInfo();
515 continue;
516 }
517
518 if (auto CTL = TL.getAs<ConstantArrayTypeLoc>()) {
519 if (const Expr *SizeExpr =
520 dyn_cast_if_present<IntegerLiteral>(Val: CTL.getSizeExpr());
521 !SizeExpr || SizeExpr->getExprLoc().isMacroID())
522 return false;
523 }
524
525 break;
526 }
527 }
528
529 // Test that the field is the last in the structure.
530 RecordDecl::field_iterator FI(
531 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
532 return ++FI == FD->getParent()->field_end();
533}
534
535TranslationUnitDecl *Decl::getTranslationUnitDecl() {
536 if (auto *TUD = dyn_cast<TranslationUnitDecl>(Val: this))
537 return TUD;
538
539 DeclContext *DC = getDeclContext();
540 assert(DC && "This decl is not contained in a translation unit!");
541
542 while (!DC->isTranslationUnit()) {
543 DC = DC->getParent();
544 assert(DC && "This decl is not contained in a translation unit!");
545 }
546
547 return cast<TranslationUnitDecl>(Val: DC);
548}
549
550ASTContext &Decl::getASTContext() const {
551 return getTranslationUnitDecl()->getASTContext();
552}
553
554/// Helper to get the language options from the ASTContext.
555/// Defined out of line to avoid depending on ASTContext.h.
556const LangOptions &Decl::getLangOpts() const {
557 return getASTContext().getLangOpts();
558}
559
560ASTMutationListener *Decl::getASTMutationListener() const {
561 return getASTContext().getASTMutationListener();
562}
563
564unsigned Decl::getMaxAlignment() const {
565 if (!hasAttrs())
566 return 0;
567
568 unsigned Align = 0;
569 const AttrVec &V = getAttrs();
570 ASTContext &Ctx = getASTContext();
571 specific_attr_iterator<AlignedAttr> I(V.begin()), E(V.end());
572 for (; I != E; ++I) {
573 if (!I->isAlignmentErrorDependent())
574 Align = std::max(a: Align, b: I->getAlignment(Ctx));
575 }
576 return Align;
577}
578
579bool Decl::isUsed(bool CheckUsedAttr) const {
580 const Decl *CanonD = getCanonicalDecl();
581 if (CanonD->Used)
582 return true;
583
584 // Check for used attribute.
585 // Ask the most recent decl, since attributes accumulate in the redecl chain.
586 if (CheckUsedAttr && getMostRecentDecl()->hasAttr<UsedAttr>())
587 return true;
588
589 // The information may have not been deserialized yet. Force deserialization
590 // to complete the needed information.
591 return getMostRecentDecl()->getCanonicalDecl()->Used;
592}
593
594void Decl::markUsed(ASTContext &C) {
595 if (isUsed(CheckUsedAttr: false))
596 return;
597
598 if (C.getASTMutationListener())
599 C.getASTMutationListener()->DeclarationMarkedUsed(D: this);
600
601 setIsUsed();
602}
603
604bool Decl::isReferenced() const {
605 if (Referenced)
606 return true;
607
608 // Check redeclarations.
609 for (const auto *I : redecls())
610 if (I->Referenced)
611 return true;
612
613 return false;
614}
615
616ExternalSourceSymbolAttr *Decl::getExternalSourceSymbolAttr() const {
617 const Decl *Definition = nullptr;
618 if (auto *ID = dyn_cast<ObjCInterfaceDecl>(Val: this)) {
619 Definition = ID->getDefinition();
620 } else if (auto *PD = dyn_cast<ObjCProtocolDecl>(Val: this)) {
621 Definition = PD->getDefinition();
622 } else if (auto *TD = dyn_cast<TagDecl>(Val: this)) {
623 Definition = TD->getDefinition();
624 }
625 if (!Definition)
626 Definition = this;
627
628 if (auto *attr = Definition->getAttr<ExternalSourceSymbolAttr>())
629 return attr;
630 if (auto *dcd = dyn_cast<Decl>(Val: getDeclContext())) {
631 return dcd->getAttr<ExternalSourceSymbolAttr>();
632 }
633
634 return nullptr;
635}
636
637bool Decl::hasDefiningAttr() const {
638 return hasAttr<AliasAttr>() || hasAttr<IFuncAttr>() ||
639 hasAttr<LoaderUninitializedAttr>();
640}
641
642const Attr *Decl::getDefiningAttr() const {
643 if (auto *AA = getAttr<AliasAttr>())
644 return AA;
645 if (auto *IFA = getAttr<IFuncAttr>())
646 return IFA;
647 if (auto *NZA = getAttr<LoaderUninitializedAttr>())
648 return NZA;
649 return nullptr;
650}
651
652static StringRef getRealizedPlatform(const AvailabilityAttr *A,
653 const ASTContext &Context) {
654 // Check if this is an App Extension "platform", and if so chop off
655 // the suffix for matching with the actual platform.
656 StringRef RealizedPlatform = A->getPlatform()->getName();
657 if (!Context.getLangOpts().AppExt)
658 return RealizedPlatform;
659 size_t suffix = RealizedPlatform.rfind(Str: "_app_extension");
660 if (suffix != StringRef::npos)
661 return RealizedPlatform.slice(Start: 0, End: suffix);
662 return RealizedPlatform;
663}
664
665/// Determine the availability of the given declaration based on
666/// the target platform.
667///
668/// When it returns an availability result other than \c AR_Available,
669/// if the \p Message parameter is non-NULL, it will be set to a
670/// string describing why the entity is unavailable.
671///
672/// FIXME: Make these strings localizable, since they end up in
673/// diagnostics.
674static AvailabilityResult CheckAvailability(ASTContext &Context,
675 const AvailabilityAttr *A,
676 std::string *Message,
677 VersionTuple EnclosingVersion) {
678 if (EnclosingVersion.empty())
679 EnclosingVersion = Context.getTargetInfo().getPlatformMinVersion();
680
681 if (EnclosingVersion.empty())
682 return AR_Available;
683
684 StringRef ActualPlatform = A->getPlatform()->getName();
685 StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
686
687 // Match the platform name.
688 if (getRealizedPlatform(A, Context) != TargetPlatform)
689 return AR_Available;
690
691 StringRef PrettyPlatformName
692 = AvailabilityAttr::getPrettyPlatformName(Platform: ActualPlatform);
693
694 if (PrettyPlatformName.empty())
695 PrettyPlatformName = ActualPlatform;
696
697 std::string HintMessage;
698 if (!A->getMessage().empty()) {
699 HintMessage = " - ";
700 HintMessage += A->getMessage();
701 }
702
703 // Make sure that this declaration has not been marked 'unavailable'.
704 if (A->getUnavailable()) {
705 if (Message) {
706 Message->clear();
707 llvm::raw_string_ostream Out(*Message);
708 Out << "not available on " << PrettyPlatformName
709 << HintMessage;
710 }
711
712 return AR_Unavailable;
713 }
714
715 // Make sure that this declaration has already been introduced.
716 if (!A->getIntroduced().empty() &&
717 EnclosingVersion < A->getIntroduced()) {
718 const IdentifierInfo *IIEnv = A->getEnvironment();
719 auto &Triple = Context.getTargetInfo().getTriple();
720 StringRef TargetEnv = Triple.getEnvironmentName();
721 StringRef EnvName =
722 llvm::Triple::getEnvironmentTypeName(Kind: Triple.getEnvironment());
723 // Matching environment or no environment on attribute.
724 if (!IIEnv || (Triple.hasEnvironment() && IIEnv->getName() == TargetEnv)) {
725 if (Message) {
726 Message->clear();
727 llvm::raw_string_ostream Out(*Message);
728 VersionTuple VTI(A->getIntroduced());
729 Out << "introduced in " << PrettyPlatformName << " " << VTI;
730 if (Triple.hasEnvironment())
731 Out << " " << EnvName;
732 Out << HintMessage;
733 }
734 }
735 // Non-matching environment or no environment on target.
736 else {
737 if (Message) {
738 Message->clear();
739 llvm::raw_string_ostream Out(*Message);
740 Out << "not available on " << PrettyPlatformName;
741 if (Triple.hasEnvironment())
742 Out << " " << EnvName;
743 Out << HintMessage;
744 }
745 }
746
747 return A->getStrict() ? AR_Unavailable : AR_NotYetIntroduced;
748 }
749
750 // Make sure that this declaration hasn't been obsoleted.
751 if (!A->getObsoleted().empty() && EnclosingVersion >= A->getObsoleted()) {
752 if (Message) {
753 Message->clear();
754 llvm::raw_string_ostream Out(*Message);
755 VersionTuple VTO(A->getObsoleted());
756 Out << "obsoleted in " << PrettyPlatformName << ' '
757 << VTO << HintMessage;
758 }
759
760 return AR_Unavailable;
761 }
762
763 // Make sure that this declaration hasn't been deprecated.
764 if (!A->getDeprecated().empty() && EnclosingVersion >= A->getDeprecated()) {
765 if (Message) {
766 Message->clear();
767 llvm::raw_string_ostream Out(*Message);
768 VersionTuple VTD(A->getDeprecated());
769 Out << "first deprecated in " << PrettyPlatformName << ' '
770 << VTD << HintMessage;
771 }
772
773 return AR_Deprecated;
774 }
775
776 return AR_Available;
777}
778
779AvailabilityResult Decl::getAvailability(std::string *Message,
780 VersionTuple EnclosingVersion,
781 StringRef *RealizedPlatform) const {
782 if (auto *FTD = dyn_cast<FunctionTemplateDecl>(Val: this))
783 return FTD->getTemplatedDecl()->getAvailability(Message, EnclosingVersion,
784 RealizedPlatform);
785
786 AvailabilityResult Result = AR_Available;
787 std::string ResultMessage;
788
789 for (const auto *A : attrs()) {
790 if (const auto *Deprecated = dyn_cast<DeprecatedAttr>(Val: A)) {
791 if (Result >= AR_Deprecated)
792 continue;
793
794 if (Message)
795 ResultMessage = std::string(Deprecated->getMessage());
796
797 Result = AR_Deprecated;
798 continue;
799 }
800
801 if (const auto *Unavailable = dyn_cast<UnavailableAttr>(Val: A)) {
802 if (Message)
803 *Message = std::string(Unavailable->getMessage());
804 return AR_Unavailable;
805 }
806
807 if (const auto *Availability = dyn_cast<AvailabilityAttr>(Val: A)) {
808 Availability = Availability->getEffectiveAttr();
809 AvailabilityResult AR = CheckAvailability(Context&: getASTContext(), A: Availability,
810 Message, EnclosingVersion);
811
812 if (AR == AR_Unavailable) {
813 if (RealizedPlatform)
814 *RealizedPlatform = Availability->getPlatform()->getName();
815 return AR_Unavailable;
816 }
817
818 if (AR > Result) {
819 Result = AR;
820 if (Message)
821 ResultMessage.swap(s&: *Message);
822 }
823 continue;
824 }
825 }
826
827 if (Message)
828 Message->swap(s&: ResultMessage);
829 return Result;
830}
831
832VersionTuple Decl::getVersionIntroduced() const {
833 const ASTContext &Context = getASTContext();
834 StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
835 for (const auto *A : attrs()) {
836 if (const auto *Availability = dyn_cast<AvailabilityAttr>(Val: A)) {
837 Availability = Availability->getEffectiveAttr();
838 if (getRealizedPlatform(A: Availability, Context) == TargetPlatform) {
839 if (!Availability->getIntroduced().empty())
840 return Availability->getIntroduced();
841 }
842 }
843 }
844 return {};
845}
846
847bool Decl::canBeWeakImported(bool &IsDefinition) const {
848 IsDefinition = false;
849
850 // Variables, if they aren't definitions.
851 if (const auto *Var = dyn_cast<VarDecl>(Val: this)) {
852 if (Var->isThisDeclarationADefinition()) {
853 IsDefinition = true;
854 return false;
855 }
856 return true;
857 }
858 // Functions, if they aren't definitions.
859 if (const auto *FD = dyn_cast<FunctionDecl>(Val: this)) {
860 if (FD->hasBody()) {
861 IsDefinition = true;
862 return false;
863 }
864 return true;
865
866 }
867 // Objective-C classes, if this is the non-fragile runtime.
868 if (isa<ObjCInterfaceDecl>(Val: this) &&
869 getASTContext().getLangOpts().ObjCRuntime.hasWeakClassImport()) {
870 return true;
871 }
872 // Nothing else.
873 return false;
874}
875
876bool Decl::isWeakImported() const {
877 bool IsDefinition;
878 if (!canBeWeakImported(IsDefinition))
879 return false;
880
881 for (const auto *A : getMostRecentDecl()->attrs()) {
882 if (isa<WeakImportAttr>(Val: A))
883 return true;
884
885 if (const auto *Availability = dyn_cast<AvailabilityAttr>(Val: A)) {
886 Availability = Availability->getEffectiveAttr();
887 if (CheckAvailability(Context&: getASTContext(), A: Availability, Message: nullptr,
888 EnclosingVersion: VersionTuple()) == AR_NotYetIntroduced)
889 return true;
890 }
891 }
892
893 return false;
894}
895
896unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
897 switch (DeclKind) {
898 case Function:
899 case CXXDeductionGuide:
900 case CXXMethod:
901 case CXXConstructor:
902 case ConstructorUsingShadow:
903 case CXXDestructor:
904 case CXXConversion:
905 case EnumConstant:
906 case Var:
907 case ImplicitParam:
908 case ParmVar:
909 case ObjCMethod:
910 case ObjCProperty:
911 case MSProperty:
912 case HLSLBuffer:
913 case HLSLRootSignature:
914 return IDNS_Ordinary;
915 case Label:
916 return IDNS_Label;
917
918 case Binding:
919 case NonTypeTemplateParm:
920 case VarTemplate:
921 case Concept:
922 // These (C++-only) declarations are found by redeclaration lookup for
923 // tag types, so we include them in the tag namespace.
924 return IDNS_Ordinary | IDNS_Tag;
925
926 case ObjCCompatibleAlias:
927 case ObjCInterface:
928 return IDNS_Ordinary | IDNS_Type;
929
930 case Typedef:
931 case TypeAlias:
932 case TemplateTypeParm:
933 case ObjCTypeParam:
934 return IDNS_Ordinary | IDNS_Type;
935
936 case UnresolvedUsingTypename:
937 return IDNS_Ordinary | IDNS_Type | IDNS_Using;
938
939 case UsingShadow:
940 return 0; // we'll actually overwrite this later
941
942 case UnresolvedUsingValue:
943 return IDNS_Ordinary | IDNS_Using;
944
945 case Using:
946 case UsingPack:
947 case UsingEnum:
948 return IDNS_Using;
949
950 case ObjCProtocol:
951 return IDNS_ObjCProtocol;
952
953 case Field:
954 case IndirectField:
955 case ObjCAtDefsField:
956 case ObjCIvar:
957 return IDNS_Member;
958
959 case Record:
960 case CXXRecord:
961 case Enum:
962 return IDNS_Tag | IDNS_Type;
963
964 case Namespace:
965 case NamespaceAlias:
966 return IDNS_Namespace;
967
968 case FunctionTemplate:
969 return IDNS_Ordinary;
970
971 case ClassTemplate:
972 case TemplateTemplateParm:
973 case TypeAliasTemplate:
974 return IDNS_Ordinary | IDNS_Tag | IDNS_Type;
975
976 case UnresolvedUsingIfExists:
977 return IDNS_Type | IDNS_Ordinary;
978
979 case OMPDeclareReduction:
980 return IDNS_OMPReduction;
981
982 case OMPDeclareMapper:
983 return IDNS_OMPMapper;
984
985 // Never have names.
986 case Friend:
987 case FriendTemplate:
988 case AccessSpec:
989 case LinkageSpec:
990 case Export:
991 case FileScopeAsm:
992 case TopLevelStmt:
993 case StaticAssert:
994 case ObjCPropertyImpl:
995 case PragmaComment:
996 case PragmaDetectMismatch:
997 case Block:
998 case Captured:
999 case OutlinedFunction:
1000 case TranslationUnit:
1001 case ExternCContext:
1002 case Decomposition:
1003 case MSGuid:
1004 case UnnamedGlobalConstant:
1005 case TemplateParamObject:
1006
1007 case UsingDirective:
1008 case BuiltinTemplate:
1009 case ClassTemplateSpecialization:
1010 case ClassTemplatePartialSpecialization:
1011 case VarTemplateSpecialization:
1012 case VarTemplatePartialSpecialization:
1013 case ObjCImplementation:
1014 case ObjCCategory:
1015 case ObjCCategoryImpl:
1016 case Import:
1017 case OMPThreadPrivate:
1018 case OMPGroupPrivate:
1019 case OMPAllocate:
1020 case OMPRequires:
1021 case OMPCapturedExpr:
1022 case Empty:
1023 case LifetimeExtendedTemporary:
1024 case RequiresExprBody:
1025 case ImplicitConceptSpecialization:
1026 case OpenACCDeclare:
1027 case OpenACCRoutine:
1028 case ExplicitInstantiation:
1029 case CXXExpansionStmt:
1030 // Never looked up by name.
1031 return 0;
1032 }
1033
1034 llvm_unreachable("Invalid DeclKind!");
1035}
1036
1037void Decl::setAttrsImpl(const AttrVec &attrs, ASTContext &Ctx) {
1038 assert(!Attrs && "Decl already contains attrs.");
1039
1040 Attrs = Ctx.allocateAttrVec();
1041 *Attrs = attrs;
1042}
1043
1044void Decl::dropAttrs() {
1045 if (!Attrs)
1046 return;
1047
1048 // The vector itself belongs to the ASTContext's allocator and is destroyed
1049 // when the context dies; only the pointer is dropped here.
1050 Attrs->clear();
1051 Attrs = nullptr;
1052}
1053
1054void Decl::addAttr(Attr *A) {
1055 if (!hasAttrs()) {
1056 setAttrs(AttrVec(1, A));
1057 return;
1058 }
1059
1060 AttrVec &Attrs = getAttrs();
1061 if (!A->isInherited()) {
1062 Attrs.push_back(Elt: A);
1063 return;
1064 }
1065
1066 // Attribute inheritance is processed after attribute parsing. To keep the
1067 // order as in the source code, add inherited attributes before non-inherited
1068 // ones.
1069 auto I = Attrs.begin(), E = Attrs.end();
1070 for (; I != E; ++I) {
1071 if (!(*I)->isInherited())
1072 break;
1073 }
1074 Attrs.insert(I, Elt: A);
1075}
1076
1077const AttrVec &Decl::getAttrs() const {
1078 assert(Attrs && "No attrs to get!");
1079 return *Attrs;
1080}
1081
1082Decl *Decl::castFromDeclContext (const DeclContext *D) {
1083 Decl::Kind DK = D->getDeclKind();
1084 switch (DK) {
1085#define DECL(NAME, BASE)
1086#define DECL_CONTEXT(NAME) \
1087 case Decl::NAME: \
1088 return static_cast<NAME##Decl *>(const_cast<DeclContext *>(D));
1089#include "clang/AST/DeclNodes.inc"
1090 default:
1091 llvm_unreachable("a decl that inherits DeclContext isn't handled");
1092 }
1093}
1094
1095DeclContext *Decl::castToDeclContext(const Decl *D) {
1096 Decl::Kind DK = D->getKind();
1097 switch(DK) {
1098#define DECL(NAME, BASE)
1099#define DECL_CONTEXT(NAME) \
1100 case Decl::NAME: \
1101 return static_cast<NAME##Decl *>(const_cast<Decl *>(D));
1102#include "clang/AST/DeclNodes.inc"
1103 default:
1104 llvm_unreachable("a decl that inherits DeclContext isn't handled");
1105 }
1106}
1107
1108SourceLocation Decl::getBodyRBrace() const {
1109 // Special handling of FunctionDecl to avoid de-serializing the body from PCH.
1110 // FunctionDecl stores EndRangeLoc for this purpose.
1111 if (const auto *FD = dyn_cast<FunctionDecl>(Val: this)) {
1112 const FunctionDecl *Definition;
1113 if (FD->hasBody(Definition))
1114 return Definition->getSourceRange().getEnd();
1115 return {};
1116 }
1117
1118 if (Stmt *Body = getBody())
1119 return Body->getSourceRange().getEnd();
1120
1121 return {};
1122}
1123
1124bool Decl::AccessDeclContextCheck() const {
1125#ifndef NDEBUG
1126 // Suppress this check if any of the following hold:
1127 // 1. this is the translation unit (and thus has no parent)
1128 // 2. this is a template parameter (and thus doesn't belong to its context)
1129 // 3. this is a non-type template parameter
1130 // 4. the context is not a record
1131 // 5. it's invalid
1132 // 6. it's a C++0x static_assert.
1133 // 7. it's a block literal declaration
1134 // 8. it's a temporary with lifetime extended due to being default value.
1135 if (isa<TranslationUnitDecl>(this) || isa<TemplateTypeParmDecl>(this) ||
1136 isa<NonTypeTemplateParmDecl>(this) || !getDeclContext() ||
1137 !isa<CXXRecordDecl>(getDeclContext()) || isInvalidDecl() ||
1138 isa<StaticAssertDecl>(this) || isa<BlockDecl>(this) ||
1139 // FIXME: a ParmVarDecl can have ClassTemplateSpecialization
1140 // as DeclContext (?).
1141 isa<ParmVarDecl>(this) ||
1142 // FIXME: a ClassTemplateSpecialization or CXXRecordDecl can have
1143 // AS_none as access specifier.
1144 isa<CXXRecordDecl>(this) || isa<LifetimeExtendedTemporaryDecl>(this))
1145 return true;
1146
1147 assert(Access != AS_none &&
1148 "Access specifier is AS_none inside a record decl");
1149#endif
1150 return true;
1151}
1152
1153bool Decl::isInExportDeclContext() const {
1154 const DeclContext *DC = getLexicalDeclContext();
1155
1156 while (DC && !isa<ExportDecl>(Val: DC))
1157 DC = DC->getLexicalParent();
1158
1159 return isa_and_nonnull<ExportDecl>(Val: DC);
1160}
1161
1162bool Decl::isModuleLocal() const {
1163 if (isa<NamespaceDecl, TranslationUnitDecl>(Val: this))
1164 return false;
1165 auto *M = getOwningModule();
1166 return M && M->isNamedModule() &&
1167 getModuleOwnershipKind() == ModuleOwnershipKind::ReachableWhenImported;
1168}
1169
1170bool Decl::isInAnotherModuleUnit() const {
1171 auto *M = getOwningModule();
1172
1173 if (!M)
1174 return false;
1175
1176 // FIXME or NOTE: maybe we need to be clear about the semantics
1177 // of clang header modules. e.g., if this lives in a clang header
1178 // module included by the current unit, should we return false
1179 // here?
1180 //
1181 // This is clear for header units as the specification says the
1182 // header units live in a synthesised translation unit. So we
1183 // can return false here.
1184 M = M->getTopLevelModule();
1185 if (!M->isNamedModule())
1186 return false;
1187
1188 return M != getASTContext().getCurrentNamedModule();
1189}
1190
1191bool Decl::isInCurrentModuleUnit() const {
1192 auto *M = getOwningModule();
1193
1194 if (!M || !M->isNamedModule())
1195 return false;
1196
1197 return M == getASTContext().getCurrentNamedModule();
1198}
1199
1200bool Decl::shouldEmitInExternalSource() const {
1201 ExternalASTSource *Source = getASTContext().getExternalSource();
1202 if (!Source)
1203 return false;
1204
1205 return Source->hasExternalDefinitions(D: this) == ExternalASTSource::EK_Always;
1206}
1207
1208bool Decl::isFromExplicitGlobalModule() const {
1209 return getOwningModule() && getOwningModule()->isExplicitGlobalModule();
1210}
1211
1212bool Decl::isFromGlobalModule() const {
1213 return getOwningModule() && getOwningModule()->isGlobalModule();
1214}
1215
1216bool Decl::isInNamedModule() const {
1217 return getOwningModule() && getOwningModule()->isNamedModule();
1218}
1219
1220bool Decl::isFromHeaderUnit() const {
1221 return getOwningModule() && getOwningModule()->isHeaderUnit();
1222}
1223
1224static Decl::Kind getKind(const Decl *D) { return D->getKind(); }
1225static Decl::Kind getKind(const DeclContext *DC) { return DC->getDeclKind(); }
1226
1227int64_t Decl::getID() const {
1228 return getASTContext().getAllocator().identifyKnownAlignedObject<Decl>(Ptr: this);
1229}
1230
1231const FunctionType *Decl::getFunctionType(bool BlocksToo) const {
1232 QualType Ty;
1233 if (const auto *D = dyn_cast<ValueDecl>(Val: this))
1234 Ty = D->getType();
1235 else if (const auto *D = dyn_cast<TypedefNameDecl>(Val: this))
1236 Ty = D->getUnderlyingType();
1237 else
1238 return nullptr;
1239
1240 if (Ty.isNull()) {
1241 // BindingDecls do not have types during parsing, so return nullptr. This is
1242 // the only known case where `Ty` is null.
1243 assert(isa<BindingDecl>(this));
1244 return nullptr;
1245 }
1246
1247 if (Ty->isFunctionPointerType())
1248 Ty = Ty->castAs<PointerType>()->getPointeeType();
1249 else if (Ty->isMemberFunctionPointerType())
1250 Ty = Ty->castAs<MemberPointerType>()->getPointeeType();
1251 else if (Ty->isFunctionReferenceType())
1252 Ty = Ty->castAs<ReferenceType>()->getPointeeType();
1253 else if (BlocksToo && Ty->isBlockPointerType())
1254 Ty = Ty->castAs<BlockPointerType>()->getPointeeType();
1255
1256 return Ty->getAs<FunctionType>();
1257}
1258
1259bool Decl::isFunctionPointerType() const {
1260 QualType Ty;
1261 if (const auto *D = dyn_cast<ValueDecl>(Val: this))
1262 Ty = D->getType();
1263 else if (const auto *D = dyn_cast<TypedefNameDecl>(Val: this))
1264 Ty = D->getUnderlyingType();
1265 else
1266 return false;
1267
1268 return Ty.getCanonicalType()->isFunctionPointerType();
1269}
1270
1271DeclContext *Decl::getNonTransparentDeclContext() {
1272 assert(getDeclContext());
1273 return getDeclContext()->getNonTransparentContext();
1274}
1275
1276/// Starting at a given context (a Decl or DeclContext), look for a
1277/// code context that is not a closure (a lambda, block, etc.).
1278template <class T> static Decl *getNonClosureContext(T *D) {
1279 if (getKind(D) == Decl::CXXMethod) {
1280 auto *MD = cast<CXXMethodDecl>(D);
1281 if (MD->getOverloadedOperator() == OO_Call &&
1282 MD->getParent()->isLambda())
1283 return getNonClosureContext(MD->getParent()->getParent());
1284 return MD;
1285 }
1286 if (auto *FD = dyn_cast<FunctionDecl>(D))
1287 return FD;
1288 if (auto *MD = dyn_cast<ObjCMethodDecl>(D))
1289 return MD;
1290 if (auto *BD = dyn_cast<BlockDecl>(D))
1291 return getNonClosureContext(BD->getParent());
1292 if (auto *CD = dyn_cast<CapturedDecl>(D))
1293 return getNonClosureContext(CD->getParent());
1294 if (auto *OFD = dyn_cast<OutlinedFunctionDecl>(D))
1295 return getNonClosureContext(OFD->getParent());
1296 return nullptr;
1297}
1298
1299Decl *Decl::getNonClosureContext() {
1300 return ::getNonClosureContext(D: this);
1301}
1302
1303Decl *DeclContext::getNonClosureAncestor() {
1304 return ::getNonClosureContext(D: this);
1305}
1306
1307//===----------------------------------------------------------------------===//
1308// DeclContext Implementation
1309//===----------------------------------------------------------------------===//
1310
1311DeclContext::DeclContext(Decl::Kind K) {
1312 DeclContextBits.DeclKind = K;
1313 setHasExternalLexicalStorage(false);
1314 setHasExternalVisibleStorage(false);
1315 setNeedToReconcileExternalVisibleStorage(false);
1316 setHasLazyLocalLexicalLookups(false);
1317 setHasLazyExternalLexicalLookups(false);
1318}
1319
1320bool DeclContext::classof(const Decl *D) {
1321 Decl::Kind DK = D->getKind();
1322 switch (DK) {
1323#define DECL(NAME, BASE)
1324#define DECL_CONTEXT(NAME) case Decl::NAME:
1325#include "clang/AST/DeclNodes.inc"
1326 return true;
1327 default:
1328 return false;
1329 }
1330}
1331
1332DeclContext::~DeclContext() = default;
1333
1334/// Find the parent context of this context that will be
1335/// used for unqualified name lookup.
1336///
1337/// Generally, the parent lookup context is the semantic context. However, for
1338/// a friend function the parent lookup context is the lexical context, which
1339/// is the class in which the friend is declared.
1340DeclContext *DeclContext::getLookupParent() {
1341 // FIXME: Find a better way to identify friends.
1342 if (isa<FunctionDecl>(Val: this))
1343 if (getParent()->getRedeclContext()->isFileContext() &&
1344 getLexicalParent()->getRedeclContext()->isRecord())
1345 return getLexicalParent();
1346
1347 // A lookup within the call operator of a lambda never looks in the lambda
1348 // class; instead, skip to the context in which that closure type is
1349 // declared.
1350 if (isLambdaCallOperator(DC: this))
1351 return getParent()->getParent();
1352
1353 return getParent();
1354}
1355
1356const BlockDecl *DeclContext::getInnermostBlockDecl() const {
1357 const DeclContext *Ctx = this;
1358
1359 do {
1360 if (Ctx->isClosure())
1361 return cast<BlockDecl>(Val: Ctx);
1362 Ctx = Ctx->getParent();
1363 } while (Ctx);
1364
1365 return nullptr;
1366}
1367
1368bool DeclContext::isInlineNamespace() const {
1369 return isNamespace() &&
1370 cast<NamespaceDecl>(Val: this)->isInline();
1371}
1372
1373bool DeclContext::isStdNamespace() const {
1374 if (!isNamespace())
1375 return false;
1376
1377 const auto *ND = cast<NamespaceDecl>(Val: this);
1378 if (ND->isInline()) {
1379 return ND->getParent()->isStdNamespace();
1380 }
1381
1382 if (!getParent()->getRedeclContext()->isTranslationUnit())
1383 return false;
1384
1385 const IdentifierInfo *II = ND->getIdentifier();
1386 return II && II->isStr(Str: "std");
1387}
1388
1389bool DeclContext::isDependentContext() const {
1390 if (isFileContext())
1391 return false;
1392
1393 if (isa<ClassTemplatePartialSpecializationDecl, CXXExpansionStmtDecl>(Val: this))
1394 return true;
1395
1396 if (const auto *Record = dyn_cast<CXXRecordDecl>(Val: this)) {
1397 if (Record->getDescribedClassTemplate())
1398 return true;
1399
1400 if (Record->isDependentLambda())
1401 return true;
1402 if (Record->isNeverDependentLambda())
1403 return false;
1404 }
1405
1406 if (const auto *Function = dyn_cast<FunctionDecl>(Val: this)) {
1407 if (Function->getDescribedFunctionTemplate())
1408 return true;
1409
1410 // Friend function declarations are dependent if their *lexical*
1411 // context is dependent.
1412 if (cast<Decl>(Val: this)->getFriendObjectKind())
1413 return getLexicalParent()->isDependentContext();
1414 }
1415
1416 // FIXME: A variable template is a dependent context, but is not a
1417 // DeclContext. A context within it (such as a lambda-expression)
1418 // should be considered dependent.
1419
1420 return getParent() && getParent()->isDependentContext();
1421}
1422
1423bool DeclContext::isTransparentContext() const {
1424 if (getDeclKind() == Decl::Enum)
1425 return !cast<EnumDecl>(Val: this)->isScoped();
1426
1427 return isa<LinkageSpecDecl, ExportDecl, HLSLBufferDecl>(Val: this);
1428}
1429
1430static bool isLinkageSpecContext(const DeclContext *DC,
1431 LinkageSpecLanguageIDs ID) {
1432 while (DC->getDeclKind() != Decl::TranslationUnit) {
1433 if (DC->getDeclKind() == Decl::LinkageSpec)
1434 return cast<LinkageSpecDecl>(Val: DC)->getLanguage() == ID;
1435 DC = DC->getLexicalParent();
1436 }
1437 return false;
1438}
1439
1440bool DeclContext::isExternCContext() const {
1441 return isLinkageSpecContext(DC: this, ID: LinkageSpecLanguageIDs::C);
1442}
1443
1444const LinkageSpecDecl *DeclContext::getExternCContext() const {
1445 const DeclContext *DC = this;
1446 while (DC->getDeclKind() != Decl::TranslationUnit) {
1447 if (DC->getDeclKind() == Decl::LinkageSpec &&
1448 cast<LinkageSpecDecl>(Val: DC)->getLanguage() == LinkageSpecLanguageIDs::C)
1449 return cast<LinkageSpecDecl>(Val: DC);
1450 DC = DC->getLexicalParent();
1451 }
1452 return nullptr;
1453}
1454
1455bool DeclContext::isExternCXXContext() const {
1456 return isLinkageSpecContext(DC: this, ID: LinkageSpecLanguageIDs::CXX);
1457}
1458
1459bool DeclContext::Encloses(const DeclContext *DC) const {
1460 if (getPrimaryContext() != this)
1461 return getPrimaryContext()->Encloses(DC);
1462
1463 for (; DC; DC = DC->getParent())
1464 if (!isa<LinkageSpecDecl, ExportDecl>(Val: DC) &&
1465 DC->getPrimaryContext() == this)
1466 return true;
1467 return false;
1468}
1469
1470bool DeclContext::LexicallyEncloses(const DeclContext *DC) const {
1471 if (getPrimaryContext() != this)
1472 return getPrimaryContext()->LexicallyEncloses(DC);
1473
1474 for (; DC; DC = DC->getLexicalParent())
1475 if (!isa<LinkageSpecDecl, ExportDecl>(Val: DC) &&
1476 DC->getPrimaryContext() == this)
1477 return true;
1478 return false;
1479}
1480
1481DeclContext *DeclContext::getNonTransparentContext() {
1482 DeclContext *DC = this;
1483 while (DC->isTransparentContext()) {
1484 DC = DC->getParent();
1485 assert(DC && "All transparent contexts should have a parent!");
1486 }
1487 return DC;
1488}
1489
1490DeclContext *DeclContext::getPrimaryContext() {
1491 switch (getDeclKind()) {
1492 case Decl::ExternCContext:
1493 case Decl::LinkageSpec:
1494 case Decl::Export:
1495 case Decl::TopLevelStmt:
1496 case Decl::Block:
1497 case Decl::Captured:
1498 case Decl::OutlinedFunction:
1499 case Decl::OMPDeclareReduction:
1500 case Decl::OMPDeclareMapper:
1501 case Decl::RequiresExprBody:
1502 case Decl::CXXExpansionStmt:
1503 // There is only one DeclContext for these entities.
1504 return this;
1505
1506 case Decl::HLSLBuffer:
1507 // Each buffer, even with the same name, is a distinct construct.
1508 // Multiple buffers with the same name are allowed for backward
1509 // compatibility.
1510 // As long as buffers have unique resource bindings the names don't matter.
1511 // The names get exposed via the CPU-side reflection API which
1512 // supports querying bindings, so we cannot remove them.
1513 return this;
1514
1515 case Decl::TranslationUnit:
1516 return static_cast<TranslationUnitDecl *>(this)->getFirstDecl();
1517 case Decl::Namespace:
1518 return static_cast<NamespaceDecl *>(this)->getFirstDecl();
1519
1520 case Decl::ObjCMethod:
1521 return this;
1522
1523 case Decl::ObjCInterface:
1524 if (auto *OID = dyn_cast<ObjCInterfaceDecl>(Val: this))
1525 if (auto *Def = OID->getDefinition())
1526 return Def;
1527 return this;
1528
1529 case Decl::ObjCProtocol:
1530 if (auto *OPD = dyn_cast<ObjCProtocolDecl>(Val: this))
1531 if (auto *Def = OPD->getDefinition())
1532 return Def;
1533 return this;
1534
1535 case Decl::ObjCCategory:
1536 return this;
1537
1538 case Decl::ObjCImplementation:
1539 case Decl::ObjCCategoryImpl:
1540 return this;
1541
1542 // If this is a tag type that has a definition or is currently
1543 // being defined, that definition is our primary context.
1544 case Decl::ClassTemplatePartialSpecialization:
1545 case Decl::ClassTemplateSpecialization:
1546 case Decl::CXXRecord:
1547 return cast<CXXRecordDecl>(Val: this)->getDefinitionOrSelf();
1548 case Decl::Record:
1549 case Decl::Enum:
1550 return cast<TagDecl>(Val: this)->getDefinitionOrSelf();
1551
1552 default:
1553 assert(getDeclKind() >= Decl::firstFunction &&
1554 getDeclKind() <= Decl::lastFunction && "Unknown DeclContext kind");
1555 return this;
1556 }
1557}
1558
1559template <typename T>
1560static void collectAllContextsImpl(T *Self,
1561 SmallVectorImpl<DeclContext *> &Contexts) {
1562 for (T *D = Self->getMostRecentDecl(); D; D = D->getPreviousDecl())
1563 Contexts.push_back(Elt: D);
1564
1565 std::reverse(first: Contexts.begin(), last: Contexts.end());
1566}
1567
1568void DeclContext::collectAllContexts(SmallVectorImpl<DeclContext *> &Contexts) {
1569 Contexts.clear();
1570
1571 Decl::Kind Kind = getDeclKind();
1572
1573 if (Kind == Decl::TranslationUnit)
1574 collectAllContextsImpl(Self: static_cast<TranslationUnitDecl *>(this), Contexts);
1575 else if (Kind == Decl::Namespace)
1576 collectAllContextsImpl(Self: static_cast<NamespaceDecl *>(this), Contexts);
1577 else
1578 Contexts.push_back(Elt: this);
1579}
1580
1581std::pair<Decl *, Decl *>
1582DeclContext::BuildDeclChain(ArrayRef<Decl *> Decls,
1583 bool FieldsAlreadyLoaded) {
1584 // Build up a chain of declarations via the Decl::NextInContextAndBits field.
1585 Decl *FirstNewDecl = nullptr;
1586 Decl *PrevDecl = nullptr;
1587 for (auto *D : Decls) {
1588 if (FieldsAlreadyLoaded && isa<FieldDecl>(Val: D))
1589 continue;
1590
1591 if (PrevDecl)
1592 PrevDecl->NextInContextAndBits.setPointer(D);
1593 else
1594 FirstNewDecl = D;
1595
1596 PrevDecl = D;
1597 }
1598
1599 return std::make_pair(x&: FirstNewDecl, y&: PrevDecl);
1600}
1601
1602/// We have just acquired external visible storage, and we already have
1603/// built a lookup map. For every name in the map, pull in the new names from
1604/// the external storage.
1605void DeclContext::reconcileExternalVisibleStorage() const {
1606 assert(hasNeedToReconcileExternalVisibleStorage() && LookupPtr);
1607 setNeedToReconcileExternalVisibleStorage(false);
1608
1609 for (auto &Lookup : *LookupPtr)
1610 Lookup.second.setHasExternalDecls();
1611}
1612
1613/// Load the declarations within this lexical storage from an
1614/// external source.
1615/// \return \c true if any declarations were added.
1616bool
1617DeclContext::LoadLexicalDeclsFromExternalStorage() const {
1618 ExternalASTSource *Source = getParentASTContext().getExternalSource();
1619 assert(hasExternalLexicalStorage() && Source && "No external storage?");
1620
1621 // Notify that we have a DeclContext that is initializing.
1622 ExternalASTSource::Deserializing ADeclContext(Source);
1623
1624 // Load the external declarations, if any.
1625 SmallVector<Decl*, 64> Decls;
1626 setHasExternalLexicalStorage(false);
1627 Source->FindExternalLexicalDecls(DC: this, Result&: Decls);
1628
1629 if (Decls.empty())
1630 return false;
1631
1632 // We may have already loaded just the fields of this record, in which case
1633 // we need to ignore them.
1634 bool FieldsAlreadyLoaded = false;
1635 if (const auto *RD = dyn_cast<RecordDecl>(Val: this))
1636 FieldsAlreadyLoaded = RD->hasLoadedFieldsFromExternalStorage();
1637
1638 // Splice the newly-read declarations into the beginning of the list
1639 // of declarations.
1640 Decl *ExternalFirst, *ExternalLast;
1641 std::tie(args&: ExternalFirst, args&: ExternalLast) =
1642 BuildDeclChain(Decls, FieldsAlreadyLoaded);
1643 ExternalLast->NextInContextAndBits.setPointer(FirstDecl);
1644 FirstDecl = ExternalFirst;
1645 if (!LastDecl)
1646 LastDecl = ExternalLast;
1647 return true;
1648}
1649
1650DeclContext::lookup_result
1651ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
1652 DeclarationName Name) {
1653 ASTContext &Context = DC->getParentASTContext();
1654 StoredDeclsMap *Map;
1655 if (!(Map = DC->LookupPtr))
1656 Map = DC->CreateStoredDeclsMap(C&: Context);
1657 if (DC->hasNeedToReconcileExternalVisibleStorage())
1658 DC->reconcileExternalVisibleStorage();
1659
1660 (*Map)[Name].removeExternalDecls();
1661
1662 return DeclContext::lookup_result();
1663}
1664
1665DeclContext::lookup_result
1666ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
1667 DeclarationName Name,
1668 ArrayRef<NamedDecl*> Decls) {
1669 ASTContext &Context = DC->getParentASTContext();
1670 StoredDeclsMap *Map;
1671 if (!(Map = DC->LookupPtr))
1672 Map = DC->CreateStoredDeclsMap(C&: Context);
1673 if (DC->hasNeedToReconcileExternalVisibleStorage())
1674 DC->reconcileExternalVisibleStorage();
1675
1676 StoredDeclsList &List = (*Map)[Name];
1677 List.replaceExternalDecls(Decls);
1678 return List.getLookupResult();
1679}
1680
1681DeclContext::decl_iterator DeclContext::decls_begin() const {
1682 if (hasExternalLexicalStorage())
1683 LoadLexicalDeclsFromExternalStorage();
1684 return decl_iterator(FirstDecl);
1685}
1686
1687bool DeclContext::decls_empty() const {
1688 if (hasExternalLexicalStorage())
1689 LoadLexicalDeclsFromExternalStorage();
1690
1691 return !FirstDecl;
1692}
1693
1694bool DeclContext::containsDecl(Decl *D) const {
1695 return (D->getLexicalDeclContext() == this &&
1696 (D->NextInContextAndBits.getPointer() || D == LastDecl));
1697}
1698
1699bool DeclContext::containsDeclAndLoad(Decl *D) const {
1700 if (hasExternalLexicalStorage())
1701 LoadLexicalDeclsFromExternalStorage();
1702 return containsDecl(D);
1703}
1704
1705/// shouldBeHidden - Determine whether a declaration which was declared
1706/// within its semantic context should be invisible to qualified name lookup.
1707static bool shouldBeHidden(NamedDecl *D) {
1708 // Skip unnamed declarations.
1709 if (!D->getDeclName())
1710 return true;
1711
1712 // Skip entities that can't be found by name lookup into a particular
1713 // context.
1714 if ((D->getIdentifierNamespace() == 0 && !isa<UsingDirectiveDecl>(Val: D)) ||
1715 D->isTemplateParameter())
1716 return true;
1717
1718 // Skip friends and local extern declarations unless they're the first
1719 // declaration of the entity.
1720 if ((D->isLocalExternDecl() || D->getFriendObjectKind()) &&
1721 D != D->getCanonicalDecl())
1722 return true;
1723
1724 // Skip template specializations.
1725 // FIXME: This feels like a hack. Should DeclarationName support
1726 // template-ids, or is there a better way to keep specializations
1727 // from being visible?
1728 if (isa<ClassTemplateSpecializationDecl>(Val: D))
1729 return true;
1730 if (auto *FD = dyn_cast<FunctionDecl>(Val: D))
1731 if (FD->isFunctionTemplateSpecialization())
1732 return true;
1733
1734 // Hide destructors that are invalid. There should always be one destructor,
1735 // but if it is an invalid decl, another one is created. We need to hide the
1736 // invalid one from places that expect exactly one destructor, like the
1737 // serialization code.
1738 if (isa<CXXDestructorDecl>(Val: D) && D->isInvalidDecl())
1739 return true;
1740
1741 return false;
1742}
1743
1744void DeclContext::removeDecl(Decl *D) {
1745 assert(D->getLexicalDeclContext() == this &&
1746 "decl being removed from non-lexical context");
1747 assert((D->NextInContextAndBits.getPointer() || D == LastDecl) &&
1748 "decl is not in decls list");
1749
1750 // Remove D from the decl chain. This is O(n) but hopefully rare.
1751 if (D == FirstDecl) {
1752 if (D == LastDecl)
1753 FirstDecl = LastDecl = nullptr;
1754 else
1755 FirstDecl = D->NextInContextAndBits.getPointer();
1756 } else {
1757 for (Decl *I = FirstDecl; true; I = I->NextInContextAndBits.getPointer()) {
1758 assert(I && "decl not found in linked list");
1759 if (I->NextInContextAndBits.getPointer() == D) {
1760 I->NextInContextAndBits.setPointer(D->NextInContextAndBits.getPointer());
1761 if (D == LastDecl) LastDecl = I;
1762 break;
1763 }
1764 }
1765 }
1766
1767 // Mark that D is no longer in the decl chain.
1768 D->NextInContextAndBits.setPointer(nullptr);
1769
1770 // Remove D from the lookup table if necessary.
1771 if (isa<NamedDecl>(Val: D)) {
1772 auto *ND = cast<NamedDecl>(Val: D);
1773
1774 // Do not try to remove the declaration if that is invisible to qualified
1775 // lookup. E.g. template specializations are skipped.
1776 if (shouldBeHidden(D: ND))
1777 return;
1778
1779 // Remove only decls that have a name
1780 if (!ND->getDeclName())
1781 return;
1782
1783 auto *DC = D->getDeclContext();
1784 do {
1785 StoredDeclsMap *Map = DC->getPrimaryContext()->LookupPtr;
1786 if (Map) {
1787 StoredDeclsMap::iterator Pos = Map->find(Val: ND->getDeclName());
1788 assert(Pos != Map->end() && "no lookup entry for decl");
1789 StoredDeclsList &List = Pos->second;
1790 List.remove(D: ND);
1791 // Clean up the entry if there are no more decls.
1792 if (List.isNull())
1793 Map->erase(I: Pos);
1794 }
1795 } while (DC->isTransparentContext() && (DC = DC->getParent()));
1796 }
1797}
1798
1799void DeclContext::addHiddenDecl(Decl *D) {
1800 assert(D->getLexicalDeclContext() == this &&
1801 "Decl inserted into wrong lexical context");
1802 assert(!D->getNextDeclInContext() && D != LastDecl &&
1803 "Decl already inserted into a DeclContext");
1804
1805 if (FirstDecl) {
1806 LastDecl->NextInContextAndBits.setPointer(D);
1807 LastDecl = D;
1808 } else {
1809 FirstDecl = LastDecl = D;
1810 }
1811
1812 // Notify a C++ record declaration that we've added a member, so it can
1813 // update its class-specific state.
1814 if (auto *Record = dyn_cast<CXXRecordDecl>(Val: this))
1815 Record->addedMember(D);
1816
1817 // If this is a newly-created (not de-serialized) import declaration, wire
1818 // it in to the list of local import declarations.
1819 if (!D->isFromASTFile()) {
1820 if (auto *Import = dyn_cast<ImportDecl>(Val: D))
1821 D->getASTContext().addedLocalImportDecl(Import);
1822 }
1823}
1824
1825void DeclContext::addDecl(Decl *D) {
1826 addHiddenDecl(D);
1827
1828 if (auto *ND = dyn_cast<NamedDecl>(Val: D))
1829 ND->getDeclContext()->getPrimaryContext()->
1830 makeDeclVisibleInContextWithFlags(D: ND, Internal: false, Rediscoverable: true);
1831}
1832
1833void DeclContext::addDeclInternal(Decl *D) {
1834 addHiddenDecl(D);
1835
1836 if (auto *ND = dyn_cast<NamedDecl>(Val: D))
1837 ND->getDeclContext()->getPrimaryContext()->
1838 makeDeclVisibleInContextWithFlags(D: ND, Internal: true, Rediscoverable: true);
1839}
1840
1841/// buildLookup - Build the lookup data structure with all of the
1842/// declarations in this DeclContext (and any other contexts linked
1843/// to it or transparent contexts nested within it) and return it.
1844///
1845/// Note that the produced map may miss out declarations from an
1846/// external source. If it does, those entries will be marked with
1847/// the 'hasExternalDecls' flag.
1848StoredDeclsMap *DeclContext::buildLookup() {
1849 assert(this == getPrimaryContext() && "buildLookup called on non-primary DC");
1850
1851 if (!hasLazyLocalLexicalLookups() &&
1852 !hasLazyExternalLexicalLookups())
1853 return LookupPtr;
1854
1855 SmallVector<DeclContext *, 2> Contexts;
1856 collectAllContexts(Contexts);
1857
1858 if (hasLazyExternalLexicalLookups()) {
1859 setHasLazyExternalLexicalLookups(false);
1860 for (auto *DC : Contexts) {
1861 if (DC->hasExternalLexicalStorage()) {
1862 bool LoadedDecls = DC->LoadLexicalDeclsFromExternalStorage();
1863 setHasLazyLocalLexicalLookups(
1864 hasLazyLocalLexicalLookups() | LoadedDecls );
1865 }
1866 }
1867
1868 if (!hasLazyLocalLexicalLookups())
1869 return LookupPtr;
1870 }
1871
1872 for (auto *DC : Contexts)
1873 buildLookupImpl(DCtx: DC, Internal: hasExternalVisibleStorage());
1874
1875 // We no longer have any lazy decls.
1876 setHasLazyLocalLexicalLookups(false);
1877 return LookupPtr;
1878}
1879
1880/// buildLookupImpl - Build part of the lookup data structure for the
1881/// declarations contained within DCtx, which will either be this
1882/// DeclContext, a DeclContext linked to it, or a transparent context
1883/// nested within it.
1884void DeclContext::buildLookupImpl(DeclContext *DCtx, bool Internal) {
1885 for (auto *D : DCtx->noload_decls()) {
1886 // Insert this declaration into the lookup structure, but only if
1887 // it's semantically within its decl context. Any other decls which
1888 // should be found in this context are added eagerly.
1889 //
1890 // If it's from an AST file, don't add it now. It'll get handled by
1891 // FindExternalVisibleDeclsByName if needed. Exception: if we're not
1892 // in C++, we do not track external visible decls for the TU, so in
1893 // that case we need to collect them all here.
1894 if (auto *ND = dyn_cast<NamedDecl>(Val: D))
1895 if (ND->getDeclContext() == DCtx && !shouldBeHidden(D: ND) &&
1896 (!ND->isFromASTFile() ||
1897 (isTranslationUnit() &&
1898 !getParentASTContext().getLangOpts().CPlusPlus)))
1899 makeDeclVisibleInContextImpl(D: ND, Internal);
1900
1901 // If this declaration is itself a transparent declaration context
1902 // or inline namespace, add the members of this declaration of that
1903 // context (recursively).
1904 if (auto *InnerCtx = dyn_cast<DeclContext>(Val: D))
1905 if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
1906 buildLookupImpl(DCtx: InnerCtx, Internal);
1907 }
1908}
1909
1910DeclContext::lookup_result
1911DeclContext::lookup(DeclarationName Name) const {
1912 // For transparent DeclContext, we should lookup in their enclosing context.
1913 if (getDeclKind() == Decl::LinkageSpec || getDeclKind() == Decl::Export)
1914 return getParent()->lookup(Name);
1915
1916 return getPrimaryContext()->lookupImpl(Name, OriginalLookupDC: this);
1917}
1918
1919DeclContext::lookup_result
1920DeclContext::lookupImpl(DeclarationName Name,
1921 const DeclContext *OriginalLookupDC) const {
1922 assert(this == getPrimaryContext() &&
1923 "lookupImpl should only be called with primary DC!");
1924 assert(getDeclKind() != Decl::LinkageSpec && getDeclKind() != Decl::Export &&
1925 "We shouldn't lookup in transparent DC.");
1926
1927 // If we have an external source, ensure that any later redeclarations of this
1928 // context have been loaded, since they may add names to the result of this
1929 // lookup (or add external visible storage).
1930 ExternalASTSource *Source = getParentASTContext().getExternalSource();
1931 if (Source)
1932 (void)cast<Decl>(Val: this)->getMostRecentDecl();
1933
1934 if (hasExternalVisibleStorage()) {
1935 assert(Source && "external visible storage but no external source?");
1936
1937 if (hasNeedToReconcileExternalVisibleStorage())
1938 reconcileExternalVisibleStorage();
1939
1940 StoredDeclsMap *Map = LookupPtr;
1941
1942 if (hasLazyLocalLexicalLookups() ||
1943 hasLazyExternalLexicalLookups())
1944 // FIXME: Make buildLookup const?
1945 Map = const_cast<DeclContext*>(this)->buildLookup();
1946
1947 if (!Map)
1948 Map = CreateStoredDeclsMap(C&: getParentASTContext());
1949
1950 // If we have a lookup result with no external decls, we are done.
1951 std::pair<StoredDeclsMap::iterator, bool> R = Map->try_emplace(Key: Name);
1952 if (!R.second && !R.first->second.hasExternalDecls())
1953 return R.first->second.getLookupResult();
1954
1955 if (Source->FindExternalVisibleDeclsByName(DC: this, Name, OriginalDC: OriginalLookupDC) ||
1956 !R.second) {
1957 if (StoredDeclsMap *Map = LookupPtr) {
1958 StoredDeclsMap::iterator I = Map->find(Val: Name);
1959 if (I != Map->end())
1960 return I->second.getLookupResult();
1961 }
1962 }
1963
1964 return {};
1965 }
1966
1967 StoredDeclsMap *Map = LookupPtr;
1968 if (hasLazyLocalLexicalLookups() ||
1969 hasLazyExternalLexicalLookups())
1970 Map = const_cast<DeclContext*>(this)->buildLookup();
1971
1972 if (!Map)
1973 return {};
1974
1975 StoredDeclsMap::iterator I = Map->find(Val: Name);
1976 if (I == Map->end())
1977 return {};
1978
1979 return I->second.getLookupResult();
1980}
1981
1982DeclContext::lookup_result
1983DeclContext::noload_lookup(DeclarationName Name) {
1984 // For transparent DeclContext, we should lookup in their enclosing context.
1985 if (getDeclKind() == Decl::LinkageSpec || getDeclKind() == Decl::Export)
1986 return getParent()->noload_lookup(Name);
1987
1988 DeclContext *PrimaryContext = getPrimaryContext();
1989 if (PrimaryContext != this)
1990 return PrimaryContext->noload_lookup(Name);
1991
1992 loadLazyLocalLexicalLookups();
1993 StoredDeclsMap *Map = LookupPtr;
1994 if (!Map)
1995 return {};
1996
1997 StoredDeclsMap::iterator I = Map->find(Val: Name);
1998 return I != Map->end() ? I->second.getLookupResult()
1999 : lookup_result();
2000}
2001
2002// If we have any lazy lexical declarations not in our lookup map, add them
2003// now. Don't import any external declarations, not even if we know we have
2004// some missing from the external visible lookups.
2005void DeclContext::loadLazyLocalLexicalLookups() {
2006 if (hasLazyLocalLexicalLookups()) {
2007 SmallVector<DeclContext *, 2> Contexts;
2008 collectAllContexts(Contexts);
2009 for (auto *Context : Contexts)
2010 buildLookupImpl(DCtx: Context, Internal: hasExternalVisibleStorage());
2011 setHasLazyLocalLexicalLookups(false);
2012 }
2013}
2014
2015void DeclContext::localUncachedLookup(DeclarationName Name,
2016 SmallVectorImpl<NamedDecl *> &Results) {
2017 Results.clear();
2018
2019 // If there's no external storage, just perform a normal lookup and copy
2020 // the results.
2021 if (!hasExternalVisibleStorage() && !hasExternalLexicalStorage() && Name) {
2022 lookup_result LookupResults = lookup(Name);
2023 llvm::append_range(C&: Results, R&: LookupResults);
2024 if (!Results.empty())
2025 return;
2026 }
2027
2028 // If we have a lookup table, check there first. Maybe we'll get lucky.
2029 // FIXME: Should we be checking these flags on the primary context?
2030 if (Name && !hasLazyLocalLexicalLookups() &&
2031 !hasLazyExternalLexicalLookups()) {
2032 if (StoredDeclsMap *Map = LookupPtr) {
2033 StoredDeclsMap::iterator Pos = Map->find(Val: Name);
2034 if (Pos != Map->end()) {
2035 Results.insert(I: Results.end(),
2036 From: Pos->second.getLookupResult().begin(),
2037 To: Pos->second.getLookupResult().end());
2038 return;
2039 }
2040 }
2041 }
2042
2043 // Slow case: grovel through the declarations in our chain looking for
2044 // matches.
2045 // FIXME: If we have lazy external declarations, this will not find them!
2046 // FIXME: Should we CollectAllContexts and walk them all here?
2047 for (Decl *D = FirstDecl; D; D = D->getNextDeclInContext()) {
2048 if (auto *ND = dyn_cast<NamedDecl>(Val: D))
2049 if (ND->getDeclName() == Name)
2050 Results.push_back(Elt: ND);
2051 }
2052}
2053
2054DeclContext *DeclContext::getRedeclContext() {
2055 DeclContext *Ctx = this;
2056
2057 // In C, a record type is the redeclaration context for its fields only. If
2058 // we arrive at a record context after skipping anything else, we should skip
2059 // the record as well. Currently, this means skipping enumerations because
2060 // they're the only transparent context that can exist within a struct or
2061 // union.
2062 bool SkipRecords = getDeclKind() == Decl::Kind::Enum &&
2063 !getParentASTContext().getLangOpts().CPlusPlus;
2064
2065 // Skip through contexts to get to the redeclaration context. Transparent
2066 // contexts are always skipped.
2067 while ((SkipRecords && Ctx->isRecord()) || Ctx->isTransparentContext())
2068 Ctx = Ctx->getParent();
2069 return Ctx;
2070}
2071
2072DeclContext *DeclContext::getEnclosingNamespaceContext() {
2073 DeclContext *Ctx = this;
2074 // Skip through non-namespace, non-translation-unit contexts.
2075 while (!Ctx->isFileContext())
2076 Ctx = Ctx->getParent();
2077 return Ctx->getPrimaryContext();
2078}
2079
2080RecordDecl *DeclContext::getOuterLexicalRecordContext() {
2081 // Loop until we find a non-record context.
2082 RecordDecl *OutermostRD = nullptr;
2083 DeclContext *DC = this;
2084 while (DC->isRecord()) {
2085 OutermostRD = cast<RecordDecl>(Val: DC);
2086 DC = DC->getLexicalParent();
2087 }
2088 return OutermostRD;
2089}
2090
2091DeclContext *DeclContext::getEnclosingNonExpansionStatementContext() {
2092 DeclContext *DC = this;
2093 while (isa<CXXExpansionStmtDecl>(Val: DC))
2094 DC = DC->getParent();
2095 return DC;
2096}
2097
2098FunctionDecl *DeclContext::getEnclosingFunction() {
2099 return dyn_cast<FunctionDecl>(Val: getEnclosingNonExpansionStatementContext());
2100}
2101
2102FunctionDecl *DeclContext::castEnclosingFunction() {
2103 return cast<FunctionDecl>(Val: getEnclosingNonExpansionStatementContext());
2104}
2105
2106bool DeclContext::InEnclosingNamespaceSetOf(const DeclContext *O) const {
2107 // For non-file contexts, this is equivalent to Equals.
2108 if (!isFileContext())
2109 return O->Equals(DC: this);
2110
2111 do {
2112 if (O->Equals(DC: this))
2113 return true;
2114
2115 const auto *NS = dyn_cast<NamespaceDecl>(Val: O);
2116 if (!NS || !NS->isInline())
2117 break;
2118 O = NS->getParent();
2119 } while (O);
2120
2121 return false;
2122}
2123
2124void DeclContext::makeDeclVisibleInContext(NamedDecl *D) {
2125 DeclContext *PrimaryDC = this->getPrimaryContext();
2126 DeclContext *DeclDC = D->getDeclContext()->getPrimaryContext();
2127 // If the decl is being added outside of its semantic decl context, we
2128 // need to ensure that we eagerly build the lookup information for it.
2129 PrimaryDC->makeDeclVisibleInContextWithFlags(D, Internal: false, Rediscoverable: PrimaryDC == DeclDC);
2130}
2131
2132void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
2133 bool Recoverable) {
2134 assert(this == getPrimaryContext() && "expected a primary DC");
2135
2136 if (!isLookupContext()) {
2137 if (isTransparentContext())
2138 getParent()->getPrimaryContext()
2139 ->makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
2140 return;
2141 }
2142
2143 // Skip declarations which should be invisible to name lookup.
2144 if (shouldBeHidden(D))
2145 return;
2146
2147 // If we already have a lookup data structure, perform the insertion into
2148 // it. If we might have externally-stored decls with this name, look them
2149 // up and perform the insertion. If this decl was declared outside its
2150 // semantic context, buildLookup won't add it, so add it now.
2151 //
2152 // FIXME: As a performance hack, don't add such decls into the translation
2153 // unit unless we're in C++, since qualified lookup into the TU is never
2154 // performed.
2155 if (LookupPtr || hasExternalVisibleStorage() ||
2156 ((!Recoverable || D->getDeclContext() != D->getLexicalDeclContext()) &&
2157 (getParentASTContext().getLangOpts().CPlusPlus ||
2158 !isTranslationUnit()))) {
2159 // If we have lazily omitted any decls, they might have the same name as
2160 // the decl which we are adding, so build a full lookup table before adding
2161 // this decl.
2162 buildLookup();
2163 makeDeclVisibleInContextImpl(D, Internal);
2164 } else {
2165 setHasLazyLocalLexicalLookups(true);
2166 }
2167
2168 // If we are a transparent context or inline namespace, insert into our
2169 // parent context, too. This operation is recursive.
2170 if (isTransparentContext() || isInlineNamespace())
2171 getParent()->getPrimaryContext()->
2172 makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
2173
2174 auto *DCAsDecl = cast<Decl>(Val: this);
2175 // Notify that a decl was made visible unless we are a Tag being defined.
2176 if (!(isa<TagDecl>(Val: DCAsDecl) && cast<TagDecl>(Val: DCAsDecl)->isBeingDefined()))
2177 if (ASTMutationListener *L = DCAsDecl->getASTMutationListener())
2178 L->AddedVisibleDecl(DC: this, D);
2179}
2180
2181void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
2182 // Find or create the stored declaration map.
2183 StoredDeclsMap *Map = LookupPtr;
2184 if (!Map) {
2185 ASTContext *C = &getParentASTContext();
2186 Map = CreateStoredDeclsMap(C&: *C);
2187 }
2188
2189 // If there is an external AST source, load any declarations it knows about
2190 // with this declaration's name.
2191 // If the lookup table contains an entry about this name it means that we
2192 // have already checked the external source.
2193 if (!Internal)
2194 if (ExternalASTSource *Source = getParentASTContext().getExternalSource())
2195 if (hasExternalVisibleStorage() && !Map->contains(Val: D->getDeclName()))
2196 Source->FindExternalVisibleDeclsByName(DC: this, Name: D->getDeclName(),
2197 OriginalDC: D->getDeclContext());
2198
2199 // Insert this declaration into the map.
2200 StoredDeclsList &DeclNameEntries = (*Map)[D->getDeclName()];
2201
2202 if (Internal) {
2203 // If this is being added as part of loading an external declaration,
2204 // this may not be the only external declaration with this name.
2205 // In this case, we never try to replace an existing declaration; we'll
2206 // handle that when we finalize the list of declarations for this name.
2207 DeclNameEntries.setHasExternalDecls();
2208 DeclNameEntries.prependDeclNoReplace(D);
2209 return;
2210 }
2211
2212 DeclNameEntries.addOrReplaceDecl(D);
2213}
2214
2215UsingDirectiveDecl *DeclContext::udir_iterator::operator*() const {
2216 return cast<UsingDirectiveDecl>(Val: *I);
2217}
2218
2219/// Returns iterator range [First, Last) of UsingDirectiveDecls stored within
2220/// this context.
2221DeclContext::udir_range DeclContext::using_directives() const {
2222 // FIXME: Use something more efficient than normal lookup for using
2223 // directives. In C++, using directives are looked up more than anything else.
2224 lookup_result Result = lookup(Name: UsingDirectiveDecl::getName());
2225 return udir_range(Result.begin(), Result.end());
2226}
2227
2228//===----------------------------------------------------------------------===//
2229// Creation and Destruction of StoredDeclsMaps. //
2230//===----------------------------------------------------------------------===//
2231
2232StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
2233 assert(!LookupPtr && "context already has a decls map");
2234 assert(getPrimaryContext() == this &&
2235 "creating decls map on non-primary context");
2236
2237 StoredDeclsMap *M;
2238 bool Dependent = isDependentContext();
2239 if (Dependent)
2240 M = new DependentStoredDeclsMap();
2241 else
2242 M = new StoredDeclsMap();
2243 M->Previous = C.LastSDM;
2244 C.LastSDM = llvm::PointerIntPair<StoredDeclsMap*,1>(M, Dependent);
2245 LookupPtr = M;
2246 return M;
2247}
2248
2249void ASTContext::ReleaseDeclContextMaps() {
2250 // It's okay to delete DependentStoredDeclsMaps via a StoredDeclsMap
2251 // pointer because the subclass doesn't add anything that needs to
2252 // be deleted.
2253 StoredDeclsMap::DestroyAll(Map: LastSDM.getPointer(), Dependent: LastSDM.getInt());
2254 LastSDM.setPointer(nullptr);
2255}
2256
2257void StoredDeclsMap::DestroyAll(StoredDeclsMap *Map, bool Dependent) {
2258 while (Map) {
2259 // Advance the iteration before we invalidate memory.
2260 llvm::PointerIntPair<StoredDeclsMap*,1> Next = Map->Previous;
2261
2262 if (Dependent)
2263 delete static_cast<DependentStoredDeclsMap*>(Map);
2264 else
2265 delete Map;
2266
2267 Map = Next.getPointer();
2268 Dependent = Next.getInt();
2269 }
2270}
2271
2272DependentDiagnostic *DependentDiagnostic::Create(ASTContext &C,
2273 DeclContext *Parent,
2274 const PartialDiagnostic &PDiag) {
2275 assert(Parent->isDependentContext()
2276 && "cannot iterate dependent diagnostics of non-dependent context");
2277 Parent = Parent->getPrimaryContext();
2278 if (!Parent->LookupPtr)
2279 Parent->CreateStoredDeclsMap(C);
2280
2281 auto *Map = static_cast<DependentStoredDeclsMap *>(Parent->LookupPtr);
2282
2283 // Allocate the copy of the PartialDiagnostic via the ASTContext's
2284 // BumpPtrAllocator, rather than the ASTContext itself.
2285 DiagnosticStorage *DiagStorage = nullptr;
2286 if (PDiag.hasStorage())
2287 DiagStorage = new (C) DiagnosticStorage;
2288
2289 auto *DD = new (C) DependentDiagnostic(PDiag, DiagStorage);
2290
2291 // TODO: Maybe we shouldn't reverse the order during insertion.
2292 DD->NextDiagnostic = Map->FirstDiagnostic;
2293 Map->FirstDiagnostic = DD;
2294
2295 return DD;
2296}
2297
2298unsigned DeclIDBase::getLocalDeclIndex() const {
2299 return ID & llvm::maskTrailingOnes<DeclID>(N: 32);
2300}
2301