1 //===--- JSONNodeDumper.h - Printing of AST nodes to JSON -----------------===//
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 AST dumping of components of individual AST nodes to
11 // a JSON.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_AST_JSONNODEDUMPER_H
16 #define LLVM_CLANG_AST_JSONNODEDUMPER_H
17 
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/ASTDumperUtils.h"
20 #include "clang/AST/ASTNodeTraverser.h"
21 #include "clang/AST/AttrVisitor.h"
22 #include "clang/AST/CommentCommandTraits.h"
23 #include "clang/AST/CommentVisitor.h"
24 #include "clang/AST/ExprCXX.h"
25 #include "clang/AST/Mangle.h"
26 #include "clang/AST/Type.h"
27 #include "llvm/Support/JSON.h"
28 
29 namespace clang {
30 
31 class APValue;
32 
33 class NodeStreamer {
34   bool FirstChild = true;
35   bool TopLevel = true;
36   llvm::SmallVector<std::function<void(bool IsLastChild)>, 32> Pending;
37 
38 protected:
39   llvm::json::OStream JOS;
40 
41 public:
42   /// Add a child of the current node.  Calls DoAddChild without arguments
43   template <typename Fn> void AddChild(Fn DoAddChild) {
44     return AddChild("", DoAddChild);
45   }
46 
47   /// Add a child of the current node with an optional label.
48   /// Calls DoAddChild without arguments.
49   template <typename Fn> void AddChild(StringRef Label, Fn DoAddChild) {
50     // If we're at the top level, there's nothing interesting to do; just
51     // run the dumper.
52     if (TopLevel) {
53       TopLevel = false;
54       JOS.objectBegin();
55 
56       DoAddChild();
57 
58       while (!Pending.empty()) {
59         Pending.back()(true);
60         Pending.pop_back();
61       }
62 
63       JOS.objectEnd();
64       TopLevel = true;
65       return;
66     }
67 
68     // We need to capture an owning-string in the lambda because the lambda
69     // is invoked in a deferred manner.
70     std::string LabelStr(!Label.empty() ? Label : "inner");
71     bool WasFirstChild = FirstChild;
72     auto DumpWithIndent = [=](bool IsLastChild) {
73       if (WasFirstChild) {
74         JOS.attributeBegin(LabelStr);
75         JOS.arrayBegin();
76       }
77 
78       FirstChild = true;
79       unsigned Depth = Pending.size();
80       JOS.objectBegin();
81 
82       DoAddChild();
83 
84       // If any children are left, they're the last at their nesting level.
85       // Dump those ones out now.
86       while (Depth < Pending.size()) {
87         Pending.back()(true);
88         this->Pending.pop_back();
89       }
90 
91       JOS.objectEnd();
92 
93       if (IsLastChild) {
94         JOS.arrayEnd();
95         JOS.attributeEnd();
96       }
97     };
98 
99     if (FirstChild) {
100       Pending.push_back(std::move(DumpWithIndent));
101     } else {
102       Pending.back()(false);
103       Pending.back() = std::move(DumpWithIndent);
104     }
105     FirstChild = false;
106   }
107 
108   NodeStreamer(raw_ostream &OS) : JOS(OS, 2) {}
109 };
110 
111 // Dumps AST nodes in JSON format. There is no implied stability for the
112 // content or format of the dump between major releases of Clang, other than it
113 // being valid JSON output. Further, there is no requirement that the
114 // information dumped is a complete representation of the AST, only that the
115 // information presented is correct.
116 class JSONNodeDumper
117     : public ConstAttrVisitor<JSONNodeDumper>,
118       public comments::ConstCommentVisitor<JSONNodeDumper, void,
119                                            const comments::FullComment *>,
120       public ConstTemplateArgumentVisitor<JSONNodeDumper>,
121       public ConstStmtVisitor<JSONNodeDumper>,
122       public TypeVisitor<JSONNodeDumper>,
123       public ConstDeclVisitor<JSONNodeDumper>,
124       public NodeStreamer {
125   friend class JSONDumper;
126 
127   const SourceManager &SM;
128   ASTContext& Ctx;
129   ASTNameGenerator ASTNameGen;
130   PrintingPolicy PrintPolicy;
131   const comments::CommandTraits *Traits;
132   StringRef LastLocFilename, LastLocPresumedFilename;
133   unsigned LastLocLine, LastLocPresumedLine;
134 
135   using InnerAttrVisitor = ConstAttrVisitor<JSONNodeDumper>;
136   using InnerCommentVisitor =
137       comments::ConstCommentVisitor<JSONNodeDumper, void,
138                                     const comments::FullComment *>;
139   using InnerTemplateArgVisitor = ConstTemplateArgumentVisitor<JSONNodeDumper>;
140   using InnerStmtVisitor = ConstStmtVisitor<JSONNodeDumper>;
141   using InnerTypeVisitor = TypeVisitor<JSONNodeDumper>;
142   using InnerDeclVisitor = ConstDeclVisitor<JSONNodeDumper>;
143 
144   void attributeOnlyIfTrue(StringRef Key, bool Value) {
145     if (Value)
146       JOS.attribute(Key, Value);
147   }
148 
149   void writeIncludeStack(PresumedLoc Loc, bool JustFirst = false);
150 
151   // Writes the attributes of a SourceLocation object without.
152   void writeBareSourceLocation(SourceLocation Loc, bool IsSpelling);
153 
154   // Writes the attributes of a SourceLocation to JSON based on its presumed
155   // spelling location. If the given location represents a macro invocation,
156   // this outputs two sub-objects: one for the spelling and one for the
157   // expansion location.
158   void writeSourceLocation(SourceLocation Loc);
159   void writeSourceRange(SourceRange R);
160   std::string createPointerRepresentation(const void *Ptr);
161   llvm::json::Object createQualType(QualType QT, bool Desugar = true);
162   llvm::json::Object createBareDeclRef(const Decl *D);
163   void writeBareDeclRef(const Decl *D);
164   llvm::json::Object createCXXRecordDefinitionData(const CXXRecordDecl *RD);
165   llvm::json::Object createCXXBaseSpecifier(const CXXBaseSpecifier &BS);
166   std::string createAccessSpecifier(AccessSpecifier AS);
167   llvm::json::Array createCastPath(const CastExpr *C);
168 
169   void writePreviousDeclImpl(...) {}
170 
171   template <typename T> void writePreviousDeclImpl(const Mergeable<T> *D) {
172     const T *First = D->getFirstDecl();
173     if (First != D)
174       JOS.attribute("firstRedecl", createPointerRepresentation(First));
175   }
176 
177   template <typename T> void writePreviousDeclImpl(const Redeclarable<T> *D) {
178     const T *Prev = D->getPreviousDecl();
179     if (Prev)
180       JOS.attribute("previousDecl", createPointerRepresentation(Prev));
181   }
182   void addPreviousDeclaration(const Decl *D);
183 
184   StringRef getCommentCommandName(unsigned CommandID) const;
185 
186 public:
187   JSONNodeDumper(raw_ostream &OS, const SourceManager &SrcMgr, ASTContext &Ctx,
188                  const PrintingPolicy &PrintPolicy,
189                  const comments::CommandTraits *Traits)
190       : NodeStreamer(OS), SM(SrcMgr), Ctx(Ctx), ASTNameGen(Ctx),
191         PrintPolicy(PrintPolicy), Traits(Traits), LastLocLine(0),
192         LastLocPresumedLine(0) {}
193 
194   void Visit(const Attr *A);
195   void Visit(const Stmt *Node);
196   void Visit(const Type *T);
197   void Visit(QualType T);
198   void Visit(const Decl *D);
199 
200   void Visit(const comments::Comment *C, const comments::FullComment *FC);
201   void Visit(const TemplateArgument &TA, SourceRange R = {},
202              const Decl *From = nullptr, StringRef Label = {});
203   void Visit(const CXXCtorInitializer *Init);
204   void Visit(const OMPClause *C);
205   void Visit(const BlockDecl::Capture &C);
206   void Visit(const GenericSelectionExpr::ConstAssociation &A);
207   void Visit(const APValue &Value, QualType Ty);
208 
209   void VisitTypedefType(const TypedefType *TT);
210   void VisitFunctionType(const FunctionType *T);
211   void VisitFunctionProtoType(const FunctionProtoType *T);
212   void VisitRValueReferenceType(const ReferenceType *RT);
213   void VisitArrayType(const ArrayType *AT);
214   void VisitConstantArrayType(const ConstantArrayType *CAT);
215   void VisitDependentSizedExtVectorType(const DependentSizedExtVectorType *VT);
216   void VisitVectorType(const VectorType *VT);
217   void VisitUnresolvedUsingType(const UnresolvedUsingType *UUT);
218   void VisitUnaryTransformType(const UnaryTransformType *UTT);
219   void VisitTagType(const TagType *TT);
220   void VisitTemplateTypeParmType(const TemplateTypeParmType *TTPT);
221   void VisitAutoType(const AutoType *AT);
222   void VisitTemplateSpecializationType(const TemplateSpecializationType *TST);
223   void VisitInjectedClassNameType(const InjectedClassNameType *ICNT);
224   void VisitObjCInterfaceType(const ObjCInterfaceType *OIT);
225   void VisitPackExpansionType(const PackExpansionType *PET);
226   void VisitElaboratedType(const ElaboratedType *ET);
227   void VisitMacroQualifiedType(const MacroQualifiedType *MQT);
228   void VisitMemberPointerType(const MemberPointerType *MPT);
229 
230   void VisitNamedDecl(const NamedDecl *ND);
231   void VisitTypedefDecl(const TypedefDecl *TD);
232   void VisitTypeAliasDecl(const TypeAliasDecl *TAD);
233   void VisitNamespaceDecl(const NamespaceDecl *ND);
234   void VisitUsingDirectiveDecl(const UsingDirectiveDecl *UDD);
235   void VisitNamespaceAliasDecl(const NamespaceAliasDecl *NAD);
236   void VisitUsingDecl(const UsingDecl *UD);
237   void VisitUsingShadowDecl(const UsingShadowDecl *USD);
238   void VisitVarDecl(const VarDecl *VD);
239   void VisitFieldDecl(const FieldDecl *FD);
240   void VisitFunctionDecl(const FunctionDecl *FD);
241   void VisitEnumDecl(const EnumDecl *ED);
242   void VisitEnumConstantDecl(const EnumConstantDecl *ECD);
243   void VisitRecordDecl(const RecordDecl *RD);
244   void VisitCXXRecordDecl(const CXXRecordDecl *RD);
245   void VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D);
246   void VisitNonTypeTemplateParmDecl(const NonTypeTemplateParmDecl *D);
247   void VisitTemplateTemplateParmDecl(const TemplateTemplateParmDecl *D);
248   void VisitLinkageSpecDecl(const LinkageSpecDecl *LSD);
249   void VisitAccessSpecDecl(const AccessSpecDecl *ASD);
250   void VisitFriendDecl(const FriendDecl *FD);
251 
252   void VisitObjCIvarDecl(const ObjCIvarDecl *D);
253   void VisitObjCMethodDecl(const ObjCMethodDecl *D);
254   void VisitObjCTypeParamDecl(const ObjCTypeParamDecl *D);
255   void VisitObjCCategoryDecl(const ObjCCategoryDecl *D);
256   void VisitObjCCategoryImplDecl(const ObjCCategoryImplDecl *D);
257   void VisitObjCProtocolDecl(const ObjCProtocolDecl *D);
258   void VisitObjCInterfaceDecl(const ObjCInterfaceDecl *D);
259   void VisitObjCImplementationDecl(const ObjCImplementationDecl *D);
260   void VisitObjCCompatibleAliasDecl(const ObjCCompatibleAliasDecl *D);
261   void VisitObjCPropertyDecl(const ObjCPropertyDecl *D);
262   void VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D);
263   void VisitBlockDecl(const BlockDecl *D);
264 
265   void VisitDeclRefExpr(const DeclRefExpr *DRE);
266   void VisitPredefinedExpr(const PredefinedExpr *PE);
267   void VisitUnaryOperator(const UnaryOperator *UO);
268   void VisitBinaryOperator(const BinaryOperator *BO);
269   void VisitCompoundAssignOperator(const CompoundAssignOperator *CAO);
270   void VisitMemberExpr(const MemberExpr *ME);
271   void VisitCXXNewExpr(const CXXNewExpr *NE);
272   void VisitCXXDeleteExpr(const CXXDeleteExpr *DE);
273   void VisitCXXThisExpr(const CXXThisExpr *TE);
274   void VisitCastExpr(const CastExpr *CE);
275   void VisitImplicitCastExpr(const ImplicitCastExpr *ICE);
276   void VisitCallExpr(const CallExpr *CE);
277   void VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *TTE);
278   void VisitSizeOfPackExpr(const SizeOfPackExpr *SOPE);
279   void VisitUnresolvedLookupExpr(const UnresolvedLookupExpr *ULE);
280   void VisitAddrLabelExpr(const AddrLabelExpr *ALE);
281   void VisitCXXTypeidExpr(const CXXTypeidExpr *CTE);
282   void VisitConstantExpr(const ConstantExpr *CE);
283   void VisitInitListExpr(const InitListExpr *ILE);
284   void VisitGenericSelectionExpr(const GenericSelectionExpr *GSE);
285   void VisitCXXUnresolvedConstructExpr(const CXXUnresolvedConstructExpr *UCE);
286   void VisitCXXConstructExpr(const CXXConstructExpr *CE);
287   void VisitExprWithCleanups(const ExprWithCleanups *EWC);
288   void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *BTE);
289   void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *MTE);
290   void VisitCXXDependentScopeMemberExpr(const CXXDependentScopeMemberExpr *ME);
291 
292   void VisitObjCEncodeExpr(const ObjCEncodeExpr *OEE);
293   void VisitObjCMessageExpr(const ObjCMessageExpr *OME);
294   void VisitObjCBoxedExpr(const ObjCBoxedExpr *OBE);
295   void VisitObjCSelectorExpr(const ObjCSelectorExpr *OSE);
296   void VisitObjCProtocolExpr(const ObjCProtocolExpr *OPE);
297   void VisitObjCPropertyRefExpr(const ObjCPropertyRefExpr *OPRE);
298   void VisitObjCSubscriptRefExpr(const ObjCSubscriptRefExpr *OSRE);
299   void VisitObjCIvarRefExpr(const ObjCIvarRefExpr *OIRE);
300   void VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *OBLE);
301 
302   void VisitIntegerLiteral(const IntegerLiteral *IL);
303   void VisitCharacterLiteral(const CharacterLiteral *CL);
304   void VisitFixedPointLiteral(const FixedPointLiteral *FPL);
305   void VisitFloatingLiteral(const FloatingLiteral *FL);
306   void VisitStringLiteral(const StringLiteral *SL);
307   void VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *BLE);
308 
309   void VisitIfStmt(const IfStmt *IS);
310   void VisitSwitchStmt(const SwitchStmt *SS);
311   void VisitCaseStmt(const CaseStmt *CS);
312   void VisitLabelStmt(const LabelStmt *LS);
313   void VisitGotoStmt(const GotoStmt *GS);
314   void VisitWhileStmt(const WhileStmt *WS);
315   void VisitObjCAtCatchStmt(const ObjCAtCatchStmt *OACS);
316 
317   void VisitNullTemplateArgument(const TemplateArgument &TA);
318   void VisitTypeTemplateArgument(const TemplateArgument &TA);
319   void VisitDeclarationTemplateArgument(const TemplateArgument &TA);
320   void VisitNullPtrTemplateArgument(const TemplateArgument &TA);
321   void VisitIntegralTemplateArgument(const TemplateArgument &TA);
322   void VisitTemplateTemplateArgument(const TemplateArgument &TA);
323   void VisitTemplateExpansionTemplateArgument(const TemplateArgument &TA);
324   void VisitExpressionTemplateArgument(const TemplateArgument &TA);
325   void VisitPackTemplateArgument(const TemplateArgument &TA);
326 
327   void visitTextComment(const comments::TextComment *C,
328                         const comments::FullComment *);
329   void visitInlineCommandComment(const comments::InlineCommandComment *C,
330                                  const comments::FullComment *);
331   void visitHTMLStartTagComment(const comments::HTMLStartTagComment *C,
332                                 const comments::FullComment *);
333   void visitHTMLEndTagComment(const comments::HTMLEndTagComment *C,
334                               const comments::FullComment *);
335   void visitBlockCommandComment(const comments::BlockCommandComment *C,
336                                 const comments::FullComment *);
337   void visitParamCommandComment(const comments::ParamCommandComment *C,
338                                 const comments::FullComment *FC);
339   void visitTParamCommandComment(const comments::TParamCommandComment *C,
340                                  const comments::FullComment *FC);
341   void visitVerbatimBlockComment(const comments::VerbatimBlockComment *C,
342                                  const comments::FullComment *);
343   void
344   visitVerbatimBlockLineComment(const comments::VerbatimBlockLineComment *C,
345                                 const comments::FullComment *);
346   void visitVerbatimLineComment(const comments::VerbatimLineComment *C,
347                                 const comments::FullComment *);
348 };
349 
350 class JSONDumper : public ASTNodeTraverser<JSONDumper, JSONNodeDumper> {
351   JSONNodeDumper NodeDumper;
352 
353   template <typename SpecializationDecl>
354   void writeTemplateDeclSpecialization(const SpecializationDecl *SD,
355                                        bool DumpExplicitInst,
356                                        bool DumpRefOnly) {
357     bool DumpedAny = false;
358     for (const auto *RedeclWithBadType : SD->redecls()) {
359       // FIXME: The redecls() range sometimes has elements of a less-specific
360       // type. (In particular, ClassTemplateSpecializationDecl::redecls() gives
361       // us TagDecls, and should give CXXRecordDecls).
362       const auto *Redecl = dyn_cast<SpecializationDecl>(RedeclWithBadType);
363       if (!Redecl) {
364         // Found the injected-class-name for a class template. This will be
365         // dumped as part of its surrounding class so we don't need to dump it
366         // here.
367         assert(isa<CXXRecordDecl>(RedeclWithBadType) &&
368                "expected an injected-class-name");
369         continue;
370       }
371 
372       switch (Redecl->getTemplateSpecializationKind()) {
373       case TSK_ExplicitInstantiationDeclaration:
374       case TSK_ExplicitInstantiationDefinition:
375         if (!DumpExplicitInst)
376           break;
377         LLVM_FALLTHROUGH;
378       case TSK_Undeclared:
379       case TSK_ImplicitInstantiation:
380         if (DumpRefOnly)
381           NodeDumper.AddChild([=] { NodeDumper.writeBareDeclRef(Redecl); });
382         else
383           Visit(Redecl);
384         DumpedAny = true;
385         break;
386       case TSK_ExplicitSpecialization:
387         break;
388       }
389     }
390 
391     // Ensure we dump at least one decl for each specialization.
392     if (!DumpedAny)
393       NodeDumper.AddChild([=] { NodeDumper.writeBareDeclRef(SD); });
394   }
395 
396   template <typename TemplateDecl>
397   void writeTemplateDecl(const TemplateDecl *TD, bool DumpExplicitInst) {
398     // FIXME: it would be nice to dump template parameters and specializations
399     // to their own named arrays rather than shoving them into the "inner"
400     // array. However, template declarations are currently being handled at the
401     // wrong "level" of the traversal hierarchy and so it is difficult to
402     // achieve without losing information elsewhere.
403 
404     dumpTemplateParameters(TD->getTemplateParameters());
405 
406     Visit(TD->getTemplatedDecl());
407 
408     for (const auto *Child : TD->specializations())
409       writeTemplateDeclSpecialization(Child, DumpExplicitInst,
410                                       !TD->isCanonicalDecl());
411   }
412 
413 public:
414   JSONDumper(raw_ostream &OS, const SourceManager &SrcMgr, ASTContext &Ctx,
415              const PrintingPolicy &PrintPolicy,
416              const comments::CommandTraits *Traits)
417       : NodeDumper(OS, SrcMgr, Ctx, PrintPolicy, Traits) {}
418 
419   JSONNodeDumper &doGetNodeDelegate() { return NodeDumper; }
420 
421   void VisitFunctionTemplateDecl(const FunctionTemplateDecl *FTD) {
422     writeTemplateDecl(FTD, true);
423   }
424   void VisitClassTemplateDecl(const ClassTemplateDecl *CTD) {
425     writeTemplateDecl(CTD, false);
426   }
427   void VisitVarTemplateDecl(const VarTemplateDecl *VTD) {
428     writeTemplateDecl(VTD, false);
429   }
430 };
431 
432 } // namespace clang
433 
434 #endif // LLVM_CLANG_AST_JSONNODEDUMPER_H
435