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