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