1 //===--- DeclPrinter.cpp - Printing implementation for Decl ASTs ----------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the Decl::print method, which pretty prints the
11 // AST back out to C/Objective-C/C++/Objective-C++ code.
12 //
13 //===----------------------------------------------------------------------===//
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/Attr.h"
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/DeclVisitor.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/AST/ExprCXX.h"
22 #include "clang/AST/PrettyPrinter.h"
23 #include "clang/Basic/Module.h"
24 #include "llvm/Support/raw_ostream.h"
25 using namespace clang;
26 
27 namespace {
28   class DeclPrinter : public DeclVisitor<DeclPrinter> {
29     raw_ostream &Out;
30     PrintingPolicy Policy;
31     unsigned Indentation;
32     bool PrintInstantiation;
33 
34     raw_ostream& Indent() { return Indent(Indentation); }
35     raw_ostream& Indent(unsigned Indentation);
36     void ProcessDeclGroup(SmallVectorImpl<Decl*>& Decls);
37 
38     void Print(AccessSpecifier AS);
39 
40   public:
41     DeclPrinter(raw_ostream &Out, const PrintingPolicy &Policy,
42                 unsigned Indentation = 0, bool PrintInstantiation = false)
43       : Out(Out), Policy(Policy), Indentation(Indentation),
44         PrintInstantiation(PrintInstantiation) { }
45 
46     void VisitDeclContext(DeclContext *DC, bool Indent = true);
47 
48     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
49     void VisitTypedefDecl(TypedefDecl *D);
50     void VisitTypeAliasDecl(TypeAliasDecl *D);
51     void VisitEnumDecl(EnumDecl *D);
52     void VisitRecordDecl(RecordDecl *D);
53     void VisitEnumConstantDecl(EnumConstantDecl *D);
54     void VisitEmptyDecl(EmptyDecl *D);
55     void VisitFunctionDecl(FunctionDecl *D);
56     void VisitFriendDecl(FriendDecl *D);
57     void VisitFieldDecl(FieldDecl *D);
58     void VisitVarDecl(VarDecl *D);
59     void VisitLabelDecl(LabelDecl *D);
60     void VisitParmVarDecl(ParmVarDecl *D);
61     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
62     void VisitImportDecl(ImportDecl *D);
63     void VisitStaticAssertDecl(StaticAssertDecl *D);
64     void VisitNamespaceDecl(NamespaceDecl *D);
65     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
66     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
67     void VisitCXXRecordDecl(CXXRecordDecl *D);
68     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
69     void VisitTemplateDecl(const TemplateDecl *D);
70     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
71     void VisitClassTemplateDecl(ClassTemplateDecl *D);
72     void VisitObjCMethodDecl(ObjCMethodDecl *D);
73     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
74     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
75     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
76     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
77     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
78     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
79     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
80     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
81     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
82     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
83     void VisitUsingDecl(UsingDecl *D);
84     void VisitUsingShadowDecl(UsingShadowDecl *D);
85     void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
86 
87     void PrintTemplateParameters(const TemplateParameterList *Params,
88                                  const TemplateArgumentList *Args = nullptr);
89     void prettyPrintAttributes(Decl *D);
90     void printDeclType(QualType T, StringRef DeclName, bool Pack = false);
91   };
92 }
93 
94 void Decl::print(raw_ostream &Out, unsigned Indentation,
95                  bool PrintInstantiation) const {
96   print(Out, getASTContext().getPrintingPolicy(), Indentation, PrintInstantiation);
97 }
98 
99 void Decl::print(raw_ostream &Out, const PrintingPolicy &Policy,
100                  unsigned Indentation, bool PrintInstantiation) const {
101   DeclPrinter Printer(Out, Policy, Indentation, PrintInstantiation);
102   Printer.Visit(const_cast<Decl*>(this));
103 }
104 
105 static QualType GetBaseType(QualType T) {
106   // FIXME: This should be on the Type class!
107   QualType BaseType = T;
108   while (!BaseType->isSpecifierType()) {
109     if (isa<TypedefType>(BaseType))
110       break;
111     else if (const PointerType* PTy = BaseType->getAs<PointerType>())
112       BaseType = PTy->getPointeeType();
113     else if (const BlockPointerType *BPy = BaseType->getAs<BlockPointerType>())
114       BaseType = BPy->getPointeeType();
115     else if (const ArrayType* ATy = dyn_cast<ArrayType>(BaseType))
116       BaseType = ATy->getElementType();
117     else if (const FunctionType* FTy = BaseType->getAs<FunctionType>())
118       BaseType = FTy->getReturnType();
119     else if (const VectorType *VTy = BaseType->getAs<VectorType>())
120       BaseType = VTy->getElementType();
121     else if (const ReferenceType *RTy = BaseType->getAs<ReferenceType>())
122       BaseType = RTy->getPointeeType();
123     else
124       llvm_unreachable("Unknown declarator!");
125   }
126   return BaseType;
127 }
128 
129 static QualType getDeclType(Decl* D) {
130   if (TypedefNameDecl* TDD = dyn_cast<TypedefNameDecl>(D))
131     return TDD->getUnderlyingType();
132   if (ValueDecl* VD = dyn_cast<ValueDecl>(D))
133     return VD->getType();
134   return QualType();
135 }
136 
137 void Decl::printGroup(Decl** Begin, unsigned NumDecls,
138                       raw_ostream &Out, const PrintingPolicy &Policy,
139                       unsigned Indentation) {
140   if (NumDecls == 1) {
141     (*Begin)->print(Out, Policy, Indentation);
142     return;
143   }
144 
145   Decl** End = Begin + NumDecls;
146   TagDecl* TD = dyn_cast<TagDecl>(*Begin);
147   if (TD)
148     ++Begin;
149 
150   PrintingPolicy SubPolicy(Policy);
151   if (TD && TD->isCompleteDefinition()) {
152     TD->print(Out, Policy, Indentation);
153     Out << " ";
154     SubPolicy.SuppressTag = true;
155   }
156 
157   bool isFirst = true;
158   for ( ; Begin != End; ++Begin) {
159     if (isFirst) {
160       SubPolicy.SuppressSpecifiers = false;
161       isFirst = false;
162     } else {
163       if (!isFirst) Out << ", ";
164       SubPolicy.SuppressSpecifiers = true;
165     }
166 
167     (*Begin)->print(Out, SubPolicy, Indentation);
168   }
169 }
170 
171 LLVM_DUMP_METHOD void DeclContext::dumpDeclContext() const {
172   // Get the translation unit
173   const DeclContext *DC = this;
174   while (!DC->isTranslationUnit())
175     DC = DC->getParent();
176 
177   ASTContext &Ctx = cast<TranslationUnitDecl>(DC)->getASTContext();
178   DeclPrinter Printer(llvm::errs(), Ctx.getPrintingPolicy(), 0);
179   Printer.VisitDeclContext(const_cast<DeclContext *>(this), /*Indent=*/false);
180 }
181 
182 raw_ostream& DeclPrinter::Indent(unsigned Indentation) {
183   for (unsigned i = 0; i != Indentation; ++i)
184     Out << "  ";
185   return Out;
186 }
187 
188 void DeclPrinter::prettyPrintAttributes(Decl *D) {
189   if (Policy.PolishForDeclaration)
190     return;
191 
192   if (D->hasAttrs()) {
193     AttrVec &Attrs = D->getAttrs();
194     for (AttrVec::const_iterator i=Attrs.begin(), e=Attrs.end(); i!=e; ++i) {
195       Attr *A = *i;
196       A->printPretty(Out, Policy);
197     }
198   }
199 }
200 
201 void DeclPrinter::printDeclType(QualType T, StringRef DeclName, bool Pack) {
202   // Normally, a PackExpansionType is written as T[3]... (for instance, as a
203   // template argument), but if it is the type of a declaration, the ellipsis
204   // is placed before the name being declared.
205   if (auto *PET = T->getAs<PackExpansionType>()) {
206     Pack = true;
207     T = PET->getPattern();
208   }
209   T.print(Out, Policy, (Pack ? "..." : "") + DeclName);
210 }
211 
212 void DeclPrinter::ProcessDeclGroup(SmallVectorImpl<Decl*>& Decls) {
213   this->Indent();
214   Decl::printGroup(Decls.data(), Decls.size(), Out, Policy, Indentation);
215   Out << ";\n";
216   Decls.clear();
217 
218 }
219 
220 void DeclPrinter::Print(AccessSpecifier AS) {
221   switch(AS) {
222   case AS_none:      llvm_unreachable("No access specifier!");
223   case AS_public:    Out << "public"; break;
224   case AS_protected: Out << "protected"; break;
225   case AS_private:   Out << "private"; break;
226   }
227 }
228 
229 //----------------------------------------------------------------------------
230 // Common C declarations
231 //----------------------------------------------------------------------------
232 
233 void DeclPrinter::VisitDeclContext(DeclContext *DC, bool Indent) {
234   if (Policy.TerseOutput)
235     return;
236 
237   if (Indent)
238     Indentation += Policy.Indentation;
239 
240   SmallVector<Decl*, 2> Decls;
241   for (DeclContext::decl_iterator D = DC->decls_begin(), DEnd = DC->decls_end();
242        D != DEnd; ++D) {
243 
244     // Don't print ObjCIvarDecls, as they are printed when visiting the
245     // containing ObjCInterfaceDecl.
246     if (isa<ObjCIvarDecl>(*D))
247       continue;
248 
249     // Skip over implicit declarations in pretty-printing mode.
250     if (D->isImplicit())
251       continue;
252 
253     // The next bits of code handles stuff like "struct {int x;} a,b"; we're
254     // forced to merge the declarations because there's no other way to
255     // refer to the struct in question.  This limited merging is safe without
256     // a bunch of other checks because it only merges declarations directly
257     // referring to the tag, not typedefs.
258     //
259     // Check whether the current declaration should be grouped with a previous
260     // unnamed struct.
261     QualType CurDeclType = getDeclType(*D);
262     if (!Decls.empty() && !CurDeclType.isNull()) {
263       QualType BaseType = GetBaseType(CurDeclType);
264       if (!BaseType.isNull() && isa<ElaboratedType>(BaseType))
265         BaseType = cast<ElaboratedType>(BaseType)->getNamedType();
266       if (!BaseType.isNull() && isa<TagType>(BaseType) &&
267           cast<TagType>(BaseType)->getDecl() == Decls[0]) {
268         Decls.push_back(*D);
269         continue;
270       }
271     }
272 
273     // If we have a merged group waiting to be handled, handle it now.
274     if (!Decls.empty())
275       ProcessDeclGroup(Decls);
276 
277     // If the current declaration is an unnamed tag type, save it
278     // so we can merge it with the subsequent declaration(s) using it.
279     if (isa<TagDecl>(*D) && !cast<TagDecl>(*D)->getIdentifier()) {
280       Decls.push_back(*D);
281       continue;
282     }
283 
284     if (isa<AccessSpecDecl>(*D)) {
285       Indentation -= Policy.Indentation;
286       this->Indent();
287       Print(D->getAccess());
288       Out << ":\n";
289       Indentation += Policy.Indentation;
290       continue;
291     }
292 
293     this->Indent();
294     Visit(*D);
295 
296     // FIXME: Need to be able to tell the DeclPrinter when
297     const char *Terminator = nullptr;
298     if (isa<OMPThreadPrivateDecl>(*D))
299       Terminator = nullptr;
300     else if (isa<FunctionDecl>(*D) &&
301              cast<FunctionDecl>(*D)->isThisDeclarationADefinition())
302       Terminator = nullptr;
303     else if (isa<ObjCMethodDecl>(*D) && cast<ObjCMethodDecl>(*D)->getBody())
304       Terminator = nullptr;
305     else if (isa<NamespaceDecl>(*D) || isa<LinkageSpecDecl>(*D) ||
306              isa<ObjCImplementationDecl>(*D) ||
307              isa<ObjCInterfaceDecl>(*D) ||
308              isa<ObjCProtocolDecl>(*D) ||
309              isa<ObjCCategoryImplDecl>(*D) ||
310              isa<ObjCCategoryDecl>(*D))
311       Terminator = nullptr;
312     else if (isa<EnumConstantDecl>(*D)) {
313       DeclContext::decl_iterator Next = D;
314       ++Next;
315       if (Next != DEnd)
316         Terminator = ",";
317     } else
318       Terminator = ";";
319 
320     if (Terminator)
321       Out << Terminator;
322     Out << "\n";
323   }
324 
325   if (!Decls.empty())
326     ProcessDeclGroup(Decls);
327 
328   if (Indent)
329     Indentation -= Policy.Indentation;
330 }
331 
332 void DeclPrinter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
333   VisitDeclContext(D, false);
334 }
335 
336 void DeclPrinter::VisitTypedefDecl(TypedefDecl *D) {
337   if (!Policy.SuppressSpecifiers) {
338     Out << "typedef ";
339 
340     if (D->isModulePrivate())
341       Out << "__module_private__ ";
342   }
343   D->getTypeSourceInfo()->getType().print(Out, Policy, D->getName());
344   prettyPrintAttributes(D);
345 }
346 
347 void DeclPrinter::VisitTypeAliasDecl(TypeAliasDecl *D) {
348   Out << "using " << *D;
349   prettyPrintAttributes(D);
350   Out << " = " << D->getTypeSourceInfo()->getType().getAsString(Policy);
351 }
352 
353 void DeclPrinter::VisitEnumDecl(EnumDecl *D) {
354   if (!Policy.SuppressSpecifiers && D->isModulePrivate())
355     Out << "__module_private__ ";
356   Out << "enum ";
357   if (D->isScoped()) {
358     if (D->isScopedUsingClassTag())
359       Out << "class ";
360     else
361       Out << "struct ";
362   }
363   Out << *D;
364 
365   if (D->isFixed())
366     Out << " : " << D->getIntegerType().stream(Policy);
367 
368   if (D->isCompleteDefinition()) {
369     Out << " {\n";
370     VisitDeclContext(D);
371     Indent() << "}";
372   }
373   prettyPrintAttributes(D);
374 }
375 
376 void DeclPrinter::VisitRecordDecl(RecordDecl *D) {
377   if (!Policy.SuppressSpecifiers && D->isModulePrivate())
378     Out << "__module_private__ ";
379   Out << D->getKindName();
380 
381   prettyPrintAttributes(D);
382 
383   if (D->getIdentifier())
384     Out << ' ' << *D;
385 
386   if (D->isCompleteDefinition()) {
387     Out << " {\n";
388     VisitDeclContext(D);
389     Indent() << "}";
390   }
391 }
392 
393 void DeclPrinter::VisitEnumConstantDecl(EnumConstantDecl *D) {
394   Out << *D;
395   if (Expr *Init = D->getInitExpr()) {
396     Out << " = ";
397     Init->printPretty(Out, nullptr, Policy, Indentation);
398   }
399 }
400 
401 void DeclPrinter::VisitFunctionDecl(FunctionDecl *D) {
402   CXXConstructorDecl *CDecl = dyn_cast<CXXConstructorDecl>(D);
403   CXXConversionDecl *ConversionDecl = dyn_cast<CXXConversionDecl>(D);
404   if (!Policy.SuppressSpecifiers) {
405     switch (D->getStorageClass()) {
406     case SC_None: break;
407     case SC_Extern: Out << "extern "; break;
408     case SC_Static: Out << "static "; break;
409     case SC_PrivateExtern: Out << "__private_extern__ "; break;
410     case SC_Auto: case SC_Register: case SC_OpenCLWorkGroupLocal:
411       llvm_unreachable("invalid for functions");
412     }
413 
414     if (D->isInlineSpecified())  Out << "inline ";
415     if (D->isVirtualAsWritten()) Out << "virtual ";
416     if (D->isModulePrivate())    Out << "__module_private__ ";
417     if (D->isConstexpr() && !D->isExplicitlyDefaulted()) Out << "constexpr ";
418     if ((CDecl && CDecl->isExplicitSpecified()) ||
419         (ConversionDecl && ConversionDecl->isExplicit()))
420       Out << "explicit ";
421   }
422 
423   PrintingPolicy SubPolicy(Policy);
424   SubPolicy.SuppressSpecifiers = false;
425   std::string Proto = D->getNameInfo().getAsString();
426 
427   QualType Ty = D->getType();
428   while (const ParenType *PT = dyn_cast<ParenType>(Ty)) {
429     Proto = '(' + Proto + ')';
430     Ty = PT->getInnerType();
431   }
432 
433   if (const FunctionType *AFT = Ty->getAs<FunctionType>()) {
434     const FunctionProtoType *FT = nullptr;
435     if (D->hasWrittenPrototype())
436       FT = dyn_cast<FunctionProtoType>(AFT);
437 
438     Proto += "(";
439     if (FT) {
440       llvm::raw_string_ostream POut(Proto);
441       DeclPrinter ParamPrinter(POut, SubPolicy, Indentation);
442       for (unsigned i = 0, e = D->getNumParams(); i != e; ++i) {
443         if (i) POut << ", ";
444         ParamPrinter.VisitParmVarDecl(D->getParamDecl(i));
445       }
446 
447       if (FT->isVariadic()) {
448         if (D->getNumParams()) POut << ", ";
449         POut << "...";
450       }
451     } else if (D->doesThisDeclarationHaveABody() && !D->hasPrototype()) {
452       for (unsigned i = 0, e = D->getNumParams(); i != e; ++i) {
453         if (i)
454           Proto += ", ";
455         Proto += D->getParamDecl(i)->getNameAsString();
456       }
457     }
458 
459     Proto += ")";
460 
461     if (FT) {
462       if (FT->isConst())
463         Proto += " const";
464       if (FT->isVolatile())
465         Proto += " volatile";
466       if (FT->isRestrict())
467         Proto += " restrict";
468 
469       switch (FT->getRefQualifier()) {
470       case RQ_None:
471         break;
472       case RQ_LValue:
473         Proto += " &";
474         break;
475       case RQ_RValue:
476         Proto += " &&";
477         break;
478       }
479     }
480 
481     if (FT && FT->hasDynamicExceptionSpec()) {
482       Proto += " throw(";
483       if (FT->getExceptionSpecType() == EST_MSAny)
484         Proto += "...";
485       else
486         for (unsigned I = 0, N = FT->getNumExceptions(); I != N; ++I) {
487           if (I)
488             Proto += ", ";
489 
490           Proto += FT->getExceptionType(I).getAsString(SubPolicy);
491         }
492       Proto += ")";
493     } else if (FT && isNoexceptExceptionSpec(FT->getExceptionSpecType())) {
494       Proto += " noexcept";
495       if (FT->getExceptionSpecType() == EST_ComputedNoexcept) {
496         Proto += "(";
497         llvm::raw_string_ostream EOut(Proto);
498         FT->getNoexceptExpr()->printPretty(EOut, nullptr, SubPolicy,
499                                            Indentation);
500         EOut.flush();
501         Proto += EOut.str();
502         Proto += ")";
503       }
504     }
505 
506     if (CDecl) {
507       bool HasInitializerList = false;
508       for (const auto *BMInitializer : CDecl->inits()) {
509         if (BMInitializer->isInClassMemberInitializer())
510           continue;
511 
512         if (!HasInitializerList) {
513           Proto += " : ";
514           Out << Proto;
515           Proto.clear();
516           HasInitializerList = true;
517         } else
518           Out << ", ";
519 
520         if (BMInitializer->isAnyMemberInitializer()) {
521           FieldDecl *FD = BMInitializer->getAnyMember();
522           Out << *FD;
523         } else {
524           Out << QualType(BMInitializer->getBaseClass(), 0).getAsString(Policy);
525         }
526 
527         Out << "(";
528         if (!BMInitializer->getInit()) {
529           // Nothing to print
530         } else {
531           Expr *Init = BMInitializer->getInit();
532           if (ExprWithCleanups *Tmp = dyn_cast<ExprWithCleanups>(Init))
533             Init = Tmp->getSubExpr();
534 
535           Init = Init->IgnoreParens();
536 
537           Expr *SimpleInit = nullptr;
538           Expr **Args = nullptr;
539           unsigned NumArgs = 0;
540           if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
541             Args = ParenList->getExprs();
542             NumArgs = ParenList->getNumExprs();
543           } else if (CXXConstructExpr *Construct
544                                         = dyn_cast<CXXConstructExpr>(Init)) {
545             Args = Construct->getArgs();
546             NumArgs = Construct->getNumArgs();
547           } else
548             SimpleInit = Init;
549 
550           if (SimpleInit)
551             SimpleInit->printPretty(Out, nullptr, Policy, Indentation);
552           else {
553             for (unsigned I = 0; I != NumArgs; ++I) {
554               assert(Args[I] != nullptr && "Expected non-null Expr");
555               if (isa<CXXDefaultArgExpr>(Args[I]))
556                 break;
557 
558               if (I)
559                 Out << ", ";
560               Args[I]->printPretty(Out, nullptr, Policy, Indentation);
561             }
562           }
563         }
564         Out << ")";
565         if (BMInitializer->isPackExpansion())
566           Out << "...";
567       }
568     } else if (!ConversionDecl && !isa<CXXDestructorDecl>(D)) {
569       if (FT && FT->hasTrailingReturn()) {
570         Out << "auto " << Proto << " -> ";
571         Proto.clear();
572       }
573       AFT->getReturnType().print(Out, Policy, Proto);
574       Proto.clear();
575     }
576     Out << Proto;
577   } else {
578     Ty.print(Out, Policy, Proto);
579   }
580 
581   prettyPrintAttributes(D);
582 
583   if (D->isPure())
584     Out << " = 0";
585   else if (D->isDeletedAsWritten())
586     Out << " = delete";
587   else if (D->isExplicitlyDefaulted())
588     Out << " = default";
589   else if (D->doesThisDeclarationHaveABody() && !Policy.TerseOutput) {
590     if (!D->hasPrototype() && D->getNumParams()) {
591       // This is a K&R function definition, so we need to print the
592       // parameters.
593       Out << '\n';
594       DeclPrinter ParamPrinter(Out, SubPolicy, Indentation);
595       Indentation += Policy.Indentation;
596       for (unsigned i = 0, e = D->getNumParams(); i != e; ++i) {
597         Indent();
598         ParamPrinter.VisitParmVarDecl(D->getParamDecl(i));
599         Out << ";\n";
600       }
601       Indentation -= Policy.Indentation;
602     } else
603       Out << ' ';
604 
605     if (D->getBody())
606       D->getBody()->printPretty(Out, nullptr, SubPolicy, Indentation);
607     Out << '\n';
608   }
609 }
610 
611 void DeclPrinter::VisitFriendDecl(FriendDecl *D) {
612   if (TypeSourceInfo *TSI = D->getFriendType()) {
613     unsigned NumTPLists = D->getFriendTypeNumTemplateParameterLists();
614     for (unsigned i = 0; i < NumTPLists; ++i)
615       PrintTemplateParameters(D->getFriendTypeTemplateParameterList(i));
616     Out << "friend ";
617     Out << " " << TSI->getType().getAsString(Policy);
618   }
619   else if (FunctionDecl *FD =
620       dyn_cast<FunctionDecl>(D->getFriendDecl())) {
621     Out << "friend ";
622     VisitFunctionDecl(FD);
623   }
624   else if (FunctionTemplateDecl *FTD =
625            dyn_cast<FunctionTemplateDecl>(D->getFriendDecl())) {
626     Out << "friend ";
627     VisitFunctionTemplateDecl(FTD);
628   }
629   else if (ClassTemplateDecl *CTD =
630            dyn_cast<ClassTemplateDecl>(D->getFriendDecl())) {
631     Out << "friend ";
632     VisitRedeclarableTemplateDecl(CTD);
633   }
634 }
635 
636 void DeclPrinter::VisitFieldDecl(FieldDecl *D) {
637   if (!Policy.SuppressSpecifiers && D->isMutable())
638     Out << "mutable ";
639   if (!Policy.SuppressSpecifiers && D->isModulePrivate())
640     Out << "__module_private__ ";
641 
642   Out << D->getASTContext().getUnqualifiedObjCPointerType(D->getType()).
643             stream(Policy, D->getName());
644 
645   if (D->isBitField()) {
646     Out << " : ";
647     D->getBitWidth()->printPretty(Out, nullptr, Policy, Indentation);
648   }
649 
650   Expr *Init = D->getInClassInitializer();
651   if (!Policy.SuppressInitializers && Init) {
652     if (D->getInClassInitStyle() == ICIS_ListInit)
653       Out << " ";
654     else
655       Out << " = ";
656     Init->printPretty(Out, nullptr, Policy, Indentation);
657   }
658   prettyPrintAttributes(D);
659 }
660 
661 void DeclPrinter::VisitLabelDecl(LabelDecl *D) {
662   Out << *D << ":";
663 }
664 
665 void DeclPrinter::VisitVarDecl(VarDecl *D) {
666   if (!Policy.SuppressSpecifiers) {
667     StorageClass SC = D->getStorageClass();
668     if (SC != SC_None)
669       Out << VarDecl::getStorageClassSpecifierString(SC) << " ";
670 
671     switch (D->getTSCSpec()) {
672     case TSCS_unspecified:
673       break;
674     case TSCS___thread:
675       Out << "__thread ";
676       break;
677     case TSCS__Thread_local:
678       Out << "_Thread_local ";
679       break;
680     case TSCS_thread_local:
681       Out << "thread_local ";
682       break;
683     }
684 
685     if (D->isModulePrivate())
686       Out << "__module_private__ ";
687   }
688 
689   QualType T = D->getTypeSourceInfo()
690     ? D->getTypeSourceInfo()->getType()
691     : D->getASTContext().getUnqualifiedObjCPointerType(D->getType());
692   printDeclType(T, D->getName());
693   Expr *Init = D->getInit();
694   if (!Policy.SuppressInitializers && Init) {
695     bool ImplicitInit = false;
696     if (CXXConstructExpr *Construct =
697             dyn_cast<CXXConstructExpr>(Init->IgnoreImplicit())) {
698       if (D->getInitStyle() == VarDecl::CallInit &&
699           !Construct->isListInitialization()) {
700         ImplicitInit = Construct->getNumArgs() == 0 ||
701           Construct->getArg(0)->isDefaultArgument();
702       }
703     }
704     if (!ImplicitInit) {
705       if ((D->getInitStyle() == VarDecl::CallInit) && !isa<ParenListExpr>(Init))
706         Out << "(";
707       else if (D->getInitStyle() == VarDecl::CInit) {
708         Out << " = ";
709       }
710       Init->printPretty(Out, nullptr, Policy, Indentation);
711       if ((D->getInitStyle() == VarDecl::CallInit) && !isa<ParenListExpr>(Init))
712         Out << ")";
713     }
714   }
715   prettyPrintAttributes(D);
716 }
717 
718 void DeclPrinter::VisitParmVarDecl(ParmVarDecl *D) {
719   VisitVarDecl(D);
720 }
721 
722 void DeclPrinter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
723   Out << "__asm (";
724   D->getAsmString()->printPretty(Out, nullptr, Policy, Indentation);
725   Out << ")";
726 }
727 
728 void DeclPrinter::VisitImportDecl(ImportDecl *D) {
729   Out << "@import " << D->getImportedModule()->getFullModuleName()
730       << ";\n";
731 }
732 
733 void DeclPrinter::VisitStaticAssertDecl(StaticAssertDecl *D) {
734   Out << "static_assert(";
735   D->getAssertExpr()->printPretty(Out, nullptr, Policy, Indentation);
736   if (StringLiteral *SL = D->getMessage()) {
737     Out << ", ";
738     SL->printPretty(Out, nullptr, Policy, Indentation);
739   }
740   Out << ")";
741 }
742 
743 //----------------------------------------------------------------------------
744 // C++ declarations
745 //----------------------------------------------------------------------------
746 void DeclPrinter::VisitNamespaceDecl(NamespaceDecl *D) {
747   if (D->isInline())
748     Out << "inline ";
749   Out << "namespace " << *D << " {\n";
750   VisitDeclContext(D);
751   Indent() << "}";
752 }
753 
754 void DeclPrinter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
755   Out << "using namespace ";
756   if (D->getQualifier())
757     D->getQualifier()->print(Out, Policy);
758   Out << *D->getNominatedNamespaceAsWritten();
759 }
760 
761 void DeclPrinter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
762   Out << "namespace " << *D << " = ";
763   if (D->getQualifier())
764     D->getQualifier()->print(Out, Policy);
765   Out << *D->getAliasedNamespace();
766 }
767 
768 void DeclPrinter::VisitEmptyDecl(EmptyDecl *D) {
769   prettyPrintAttributes(D);
770 }
771 
772 void DeclPrinter::VisitCXXRecordDecl(CXXRecordDecl *D) {
773   if (!Policy.SuppressSpecifiers && D->isModulePrivate())
774     Out << "__module_private__ ";
775   Out << D->getKindName();
776 
777   prettyPrintAttributes(D);
778 
779   if (D->getIdentifier())
780     Out << ' ' << *D;
781 
782   if (D->isCompleteDefinition()) {
783     // Print the base classes
784     if (D->getNumBases()) {
785       Out << " : ";
786       for (CXXRecordDecl::base_class_iterator Base = D->bases_begin(),
787              BaseEnd = D->bases_end(); Base != BaseEnd; ++Base) {
788         if (Base != D->bases_begin())
789           Out << ", ";
790 
791         if (Base->isVirtual())
792           Out << "virtual ";
793 
794         AccessSpecifier AS = Base->getAccessSpecifierAsWritten();
795         if (AS != AS_none) {
796           Print(AS);
797           Out << " ";
798         }
799         Out << Base->getType().getAsString(Policy);
800 
801         if (Base->isPackExpansion())
802           Out << "...";
803       }
804     }
805 
806     // Print the class definition
807     // FIXME: Doesn't print access specifiers, e.g., "public:"
808     Out << " {\n";
809     VisitDeclContext(D);
810     Indent() << "}";
811   }
812 }
813 
814 void DeclPrinter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
815   const char *l;
816   if (D->getLanguage() == LinkageSpecDecl::lang_c)
817     l = "C";
818   else {
819     assert(D->getLanguage() == LinkageSpecDecl::lang_cxx &&
820            "unknown language in linkage specification");
821     l = "C++";
822   }
823 
824   Out << "extern \"" << l << "\" ";
825   if (D->hasBraces()) {
826     Out << "{\n";
827     VisitDeclContext(D);
828     Indent() << "}";
829   } else
830     Visit(*D->decls_begin());
831 }
832 
833 void DeclPrinter::PrintTemplateParameters(const TemplateParameterList *Params,
834                                           const TemplateArgumentList *Args) {
835   assert(Params);
836   assert(!Args || Params->size() == Args->size());
837 
838   Out << "template <";
839 
840   for (unsigned i = 0, e = Params->size(); i != e; ++i) {
841     if (i != 0)
842       Out << ", ";
843 
844     const Decl *Param = Params->getParam(i);
845     if (const TemplateTypeParmDecl *TTP =
846           dyn_cast<TemplateTypeParmDecl>(Param)) {
847 
848       if (TTP->wasDeclaredWithTypename())
849         Out << "typename ";
850       else
851         Out << "class ";
852 
853       if (TTP->isParameterPack())
854         Out << "...";
855 
856       Out << *TTP;
857 
858       if (Args) {
859         Out << " = ";
860         Args->get(i).print(Policy, Out);
861       } else if (TTP->hasDefaultArgument()) {
862         Out << " = ";
863         Out << TTP->getDefaultArgument().getAsString(Policy);
864       };
865     } else if (const NonTypeTemplateParmDecl *NTTP =
866                  dyn_cast<NonTypeTemplateParmDecl>(Param)) {
867       StringRef Name;
868       if (IdentifierInfo *II = NTTP->getIdentifier())
869         Name = II->getName();
870       printDeclType(NTTP->getType(), Name, NTTP->isParameterPack());
871 
872       if (Args) {
873         Out << " = ";
874         Args->get(i).print(Policy, Out);
875       } else if (NTTP->hasDefaultArgument()) {
876         Out << " = ";
877         NTTP->getDefaultArgument()->printPretty(Out, nullptr, Policy,
878                                                 Indentation);
879       }
880     } else if (const TemplateTemplateParmDecl *TTPD =
881                  dyn_cast<TemplateTemplateParmDecl>(Param)) {
882       VisitTemplateDecl(TTPD);
883       // FIXME: print the default argument, if present.
884     }
885   }
886 
887   Out << "> ";
888 }
889 
890 void DeclPrinter::VisitTemplateDecl(const TemplateDecl *D) {
891   PrintTemplateParameters(D->getTemplateParameters());
892 
893   if (const TemplateTemplateParmDecl *TTP =
894         dyn_cast<TemplateTemplateParmDecl>(D)) {
895     Out << "class ";
896     if (TTP->isParameterPack())
897       Out << "...";
898     Out << D->getName();
899   } else {
900     Visit(D->getTemplatedDecl());
901   }
902 }
903 
904 void DeclPrinter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
905   if (PrintInstantiation) {
906     TemplateParameterList *Params = D->getTemplateParameters();
907     for (auto *I : D->specializations()) {
908       PrintTemplateParameters(Params, I->getTemplateSpecializationArgs());
909       Visit(I);
910     }
911   }
912 
913   return VisitRedeclarableTemplateDecl(D);
914 }
915 
916 void DeclPrinter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
917   if (PrintInstantiation) {
918     TemplateParameterList *Params = D->getTemplateParameters();
919     for (auto *I : D->specializations()) {
920       PrintTemplateParameters(Params, &I->getTemplateArgs());
921       Visit(I);
922       Out << '\n';
923     }
924   }
925 
926   return VisitRedeclarableTemplateDecl(D);
927 }
928 
929 //----------------------------------------------------------------------------
930 // Objective-C declarations
931 //----------------------------------------------------------------------------
932 
933 void DeclPrinter::VisitObjCMethodDecl(ObjCMethodDecl *OMD) {
934   if (OMD->isInstanceMethod())
935     Out << "- ";
936   else
937     Out << "+ ";
938   if (!OMD->getReturnType().isNull())
939     Out << '(' << OMD->getASTContext()
940                       .getUnqualifiedObjCPointerType(OMD->getReturnType())
941                       .getAsString(Policy) << ")";
942 
943   std::string name = OMD->getSelector().getAsString();
944   std::string::size_type pos, lastPos = 0;
945   for (const auto *PI : OMD->params()) {
946     // FIXME: selector is missing here!
947     pos = name.find_first_of(':', lastPos);
948     Out << " " << name.substr(lastPos, pos - lastPos);
949     Out << ":(" << PI->getASTContext().getUnqualifiedObjCPointerType(PI->getType()).
950                       getAsString(Policy) << ')' << *PI;
951     lastPos = pos + 1;
952   }
953 
954   if (OMD->param_begin() == OMD->param_end())
955     Out << " " << name;
956 
957   if (OMD->isVariadic())
958       Out << ", ...";
959 
960   prettyPrintAttributes(OMD);
961 
962   if (OMD->getBody() && !Policy.TerseOutput) {
963     Out << ' ';
964     OMD->getBody()->printPretty(Out, nullptr, Policy);
965   }
966   else if (Policy.PolishForDeclaration)
967     Out << ';';
968 }
969 
970 void DeclPrinter::VisitObjCImplementationDecl(ObjCImplementationDecl *OID) {
971   std::string I = OID->getNameAsString();
972   ObjCInterfaceDecl *SID = OID->getSuperClass();
973 
974   bool eolnOut = false;
975   if (SID)
976     Out << "@implementation " << I << " : " << *SID;
977   else
978     Out << "@implementation " << I;
979 
980   if (OID->ivar_size() > 0) {
981     Out << "{\n";
982     eolnOut = true;
983     Indentation += Policy.Indentation;
984     for (const auto *I : OID->ivars()) {
985       Indent() << I->getASTContext().getUnqualifiedObjCPointerType(I->getType()).
986                     getAsString(Policy) << ' ' << *I << ";\n";
987     }
988     Indentation -= Policy.Indentation;
989     Out << "}\n";
990   }
991   else if (SID || (OID->decls_begin() != OID->decls_end())) {
992     Out << "\n";
993     eolnOut = true;
994   }
995   VisitDeclContext(OID, false);
996   if (!eolnOut)
997     Out << "\n";
998   Out << "@end";
999 }
1000 
1001 void DeclPrinter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *OID) {
1002   std::string I = OID->getNameAsString();
1003   ObjCInterfaceDecl *SID = OID->getSuperClass();
1004 
1005   if (!OID->isThisDeclarationADefinition()) {
1006     Out << "@class " << I << ";";
1007     return;
1008   }
1009   bool eolnOut = false;
1010   if (SID)
1011     Out << "@interface " << I << " : " << *SID;
1012   else
1013     Out << "@interface " << I;
1014 
1015   // Protocols?
1016   const ObjCList<ObjCProtocolDecl> &Protocols = OID->getReferencedProtocols();
1017   if (!Protocols.empty()) {
1018     for (ObjCList<ObjCProtocolDecl>::iterator I = Protocols.begin(),
1019          E = Protocols.end(); I != E; ++I)
1020       Out << (I == Protocols.begin() ? '<' : ',') << **I;
1021     Out << "> ";
1022   }
1023 
1024   if (OID->ivar_size() > 0) {
1025     Out << "{\n";
1026     eolnOut = true;
1027     Indentation += Policy.Indentation;
1028     for (const auto *I : OID->ivars()) {
1029       Indent() << I->getASTContext()
1030                       .getUnqualifiedObjCPointerType(I->getType())
1031                       .getAsString(Policy) << ' ' << *I << ";\n";
1032     }
1033     Indentation -= Policy.Indentation;
1034     Out << "}\n";
1035   }
1036   else if (SID || (OID->decls_begin() != OID->decls_end())) {
1037     Out << "\n";
1038     eolnOut = true;
1039   }
1040 
1041   VisitDeclContext(OID, false);
1042   if (!eolnOut)
1043     Out << "\n";
1044   Out << "@end";
1045   // FIXME: implement the rest...
1046 }
1047 
1048 void DeclPrinter::VisitObjCProtocolDecl(ObjCProtocolDecl *PID) {
1049   if (!PID->isThisDeclarationADefinition()) {
1050     Out << "@protocol " << *PID << ";\n";
1051     return;
1052   }
1053   // Protocols?
1054   const ObjCList<ObjCProtocolDecl> &Protocols = PID->getReferencedProtocols();
1055   if (!Protocols.empty()) {
1056     Out << "@protocol " << *PID;
1057     for (ObjCList<ObjCProtocolDecl>::iterator I = Protocols.begin(),
1058          E = Protocols.end(); I != E; ++I)
1059       Out << (I == Protocols.begin() ? '<' : ',') << **I;
1060     Out << ">\n";
1061   } else
1062     Out << "@protocol " << *PID << '\n';
1063   VisitDeclContext(PID, false);
1064   Out << "@end";
1065 }
1066 
1067 void DeclPrinter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *PID) {
1068   Out << "@implementation " << *PID->getClassInterface() << '(' << *PID <<")\n";
1069 
1070   VisitDeclContext(PID, false);
1071   Out << "@end";
1072   // FIXME: implement the rest...
1073 }
1074 
1075 void DeclPrinter::VisitObjCCategoryDecl(ObjCCategoryDecl *PID) {
1076   Out << "@interface " << *PID->getClassInterface() << '(' << *PID << ")\n";
1077   if (PID->ivar_size() > 0) {
1078     Out << "{\n";
1079     Indentation += Policy.Indentation;
1080     for (const auto *I : PID->ivars())
1081       Indent() << I->getASTContext().getUnqualifiedObjCPointerType(I->getType()).
1082                     getAsString(Policy) << ' ' << *I << ";\n";
1083     Indentation -= Policy.Indentation;
1084     Out << "}\n";
1085   }
1086 
1087   VisitDeclContext(PID, false);
1088   Out << "@end";
1089 
1090   // FIXME: implement the rest...
1091 }
1092 
1093 void DeclPrinter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *AID) {
1094   Out << "@compatibility_alias " << *AID
1095       << ' ' << *AID->getClassInterface() << ";\n";
1096 }
1097 
1098 /// PrintObjCPropertyDecl - print a property declaration.
1099 ///
1100 void DeclPrinter::VisitObjCPropertyDecl(ObjCPropertyDecl *PDecl) {
1101   if (PDecl->getPropertyImplementation() == ObjCPropertyDecl::Required)
1102     Out << "@required\n";
1103   else if (PDecl->getPropertyImplementation() == ObjCPropertyDecl::Optional)
1104     Out << "@optional\n";
1105 
1106   Out << "@property";
1107   if (PDecl->getPropertyAttributes() != ObjCPropertyDecl::OBJC_PR_noattr) {
1108     bool first = true;
1109     Out << " (";
1110     if (PDecl->getPropertyAttributes() &
1111         ObjCPropertyDecl::OBJC_PR_readonly) {
1112       Out << (first ? ' ' : ',') << "readonly";
1113       first = false;
1114     }
1115 
1116     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
1117       Out << (first ? ' ' : ',') << "getter = ";
1118       PDecl->getGetterName().print(Out);
1119       first = false;
1120     }
1121     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
1122       Out << (first ? ' ' : ',') << "setter = ";
1123       PDecl->getSetterName().print(Out);
1124       first = false;
1125     }
1126 
1127     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_assign) {
1128       Out << (first ? ' ' : ',') << "assign";
1129       first = false;
1130     }
1131 
1132     if (PDecl->getPropertyAttributes() &
1133         ObjCPropertyDecl::OBJC_PR_readwrite) {
1134       Out << (first ? ' ' : ',') << "readwrite";
1135       first = false;
1136     }
1137 
1138     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain) {
1139       Out << (first ? ' ' : ',') << "retain";
1140       first = false;
1141     }
1142 
1143     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_strong) {
1144       Out << (first ? ' ' : ',') << "strong";
1145       first = false;
1146     }
1147 
1148     if (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy) {
1149       Out << (first ? ' ' : ',') << "copy";
1150       first = false;
1151     }
1152 
1153     if (PDecl->getPropertyAttributes() &
1154         ObjCPropertyDecl::OBJC_PR_nonatomic) {
1155       Out << (first ? ' ' : ',') << "nonatomic";
1156       first = false;
1157     }
1158     if (PDecl->getPropertyAttributes() &
1159         ObjCPropertyDecl::OBJC_PR_atomic) {
1160       Out << (first ? ' ' : ',') << "atomic";
1161       first = false;
1162     }
1163 
1164     (void) first; // Silence dead store warning due to idiomatic code.
1165     Out << " )";
1166   }
1167   Out << ' ' << PDecl->getASTContext().getUnqualifiedObjCPointerType(PDecl->getType()).
1168                   getAsString(Policy) << ' ' << *PDecl;
1169   if (Policy.PolishForDeclaration)
1170     Out << ';';
1171 }
1172 
1173 void DeclPrinter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *PID) {
1174   if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize)
1175     Out << "@synthesize ";
1176   else
1177     Out << "@dynamic ";
1178   Out << *PID->getPropertyDecl();
1179   if (PID->getPropertyIvarDecl())
1180     Out << '=' << *PID->getPropertyIvarDecl();
1181 }
1182 
1183 void DeclPrinter::VisitUsingDecl(UsingDecl *D) {
1184   if (!D->isAccessDeclaration())
1185     Out << "using ";
1186   if (D->hasTypename())
1187     Out << "typename ";
1188   D->getQualifier()->print(Out, Policy);
1189   Out << *D;
1190 }
1191 
1192 void
1193 DeclPrinter::VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D) {
1194   Out << "using typename ";
1195   D->getQualifier()->print(Out, Policy);
1196   Out << D->getDeclName();
1197 }
1198 
1199 void DeclPrinter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
1200   if (!D->isAccessDeclaration())
1201     Out << "using ";
1202   D->getQualifier()->print(Out, Policy);
1203   Out << D->getName();
1204 }
1205 
1206 void DeclPrinter::VisitUsingShadowDecl(UsingShadowDecl *D) {
1207   // ignore
1208 }
1209 
1210 void DeclPrinter::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
1211   Out << "#pragma omp threadprivate";
1212   if (!D->varlist_empty()) {
1213     for (OMPThreadPrivateDecl::varlist_iterator I = D->varlist_begin(),
1214                                                 E = D->varlist_end();
1215                                                 I != E; ++I) {
1216       Out << (I == D->varlist_begin() ? '(' : ',');
1217       NamedDecl *ND = cast<NamedDecl>(cast<DeclRefExpr>(*I)->getDecl());
1218       ND->printQualifiedName(Out);
1219     }
1220     Out << ")";
1221   }
1222 }
1223 
1224