1 //===--- Comment.cpp - Comment AST node implementation --------------------===//
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 #include "clang/AST/Comment.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/AST/Decl.h"
13 #include "clang/AST/DeclObjC.h"
14 #include "clang/AST/DeclTemplate.h"
15 #include "clang/Basic/CharInfo.h"
16 #include "llvm/Support/ErrorHandling.h"
17 
18 namespace clang {
19 namespace comments {
20 
21 const char *Comment::getCommentKindName() const {
22   switch (getCommentKind()) {
23   case NoCommentKind: return "NoCommentKind";
24 #define ABSTRACT_COMMENT(COMMENT)
25 #define COMMENT(CLASS, PARENT) \
26   case CLASS##Kind: \
27     return #CLASS;
28 #include "clang/AST/CommentNodes.inc"
29 #undef COMMENT
30 #undef ABSTRACT_COMMENT
31   }
32   llvm_unreachable("Unknown comment kind!");
33 }
34 
35 namespace {
36 struct good {};
37 struct bad {};
38 
39 template <typename T>
40 good implements_child_begin_end(Comment::child_iterator (T::*)() const) {
41   return good();
42 }
43 
44 LLVM_ATTRIBUTE_UNUSED
45 static inline bad implements_child_begin_end(
46                       Comment::child_iterator (Comment::*)() const) {
47   return bad();
48 }
49 
50 #define ASSERT_IMPLEMENTS_child_begin(function) \
51   (void) good(implements_child_begin_end(function))
52 
53 LLVM_ATTRIBUTE_UNUSED
54 static inline void CheckCommentASTNodes() {
55 #define ABSTRACT_COMMENT(COMMENT)
56 #define COMMENT(CLASS, PARENT) \
57   ASSERT_IMPLEMENTS_child_begin(&CLASS::child_begin); \
58   ASSERT_IMPLEMENTS_child_begin(&CLASS::child_end);
59 #include "clang/AST/CommentNodes.inc"
60 #undef COMMENT
61 #undef ABSTRACT_COMMENT
62 }
63 
64 #undef ASSERT_IMPLEMENTS_child_begin
65 
66 } // end unnamed namespace
67 
68 Comment::child_iterator Comment::child_begin() const {
69   switch (getCommentKind()) {
70   case NoCommentKind: llvm_unreachable("comment without a kind");
71 #define ABSTRACT_COMMENT(COMMENT)
72 #define COMMENT(CLASS, PARENT) \
73   case CLASS##Kind: \
74     return static_cast<const CLASS *>(this)->child_begin();
75 #include "clang/AST/CommentNodes.inc"
76 #undef COMMENT
77 #undef ABSTRACT_COMMENT
78   }
79   llvm_unreachable("Unknown comment kind!");
80 }
81 
82 Comment::child_iterator Comment::child_end() const {
83   switch (getCommentKind()) {
84   case NoCommentKind: llvm_unreachable("comment without a kind");
85 #define ABSTRACT_COMMENT(COMMENT)
86 #define COMMENT(CLASS, PARENT) \
87   case CLASS##Kind: \
88     return static_cast<const CLASS *>(this)->child_end();
89 #include "clang/AST/CommentNodes.inc"
90 #undef COMMENT
91 #undef ABSTRACT_COMMENT
92   }
93   llvm_unreachable("Unknown comment kind!");
94 }
95 
96 bool TextComment::isWhitespaceNoCache() const {
97   for (StringRef::const_iterator I = Text.begin(), E = Text.end();
98        I != E; ++I) {
99     if (!clang::isWhitespace(*I))
100       return false;
101   }
102   return true;
103 }
104 
105 bool ParagraphComment::isWhitespaceNoCache() const {
106   for (child_iterator I = child_begin(), E = child_end(); I != E; ++I) {
107     if (const TextComment *TC = dyn_cast<TextComment>(*I)) {
108       if (!TC->isWhitespace())
109         return false;
110     } else
111       return false;
112   }
113   return true;
114 }
115 
116 static TypeLoc lookThroughTypedefOrTypeAliasLocs(TypeLoc &SrcTL) {
117   TypeLoc TL = SrcTL.IgnoreParens();
118 
119   // Look through qualified types.
120   if (QualifiedTypeLoc QualifiedTL = TL.getAs<QualifiedTypeLoc>())
121     return QualifiedTL.getUnqualifiedLoc();
122   // Look through pointer types.
123   if (PointerTypeLoc PointerTL = TL.getAs<PointerTypeLoc>())
124     return PointerTL.getPointeeLoc().getUnqualifiedLoc();
125   // Look through reference types.
126   if (ReferenceTypeLoc ReferenceTL = TL.getAs<ReferenceTypeLoc>())
127     return ReferenceTL.getPointeeLoc().getUnqualifiedLoc();
128   // Look through adjusted types.
129   if (AdjustedTypeLoc ATL = TL.getAs<AdjustedTypeLoc>())
130     return ATL.getOriginalLoc();
131   if (BlockPointerTypeLoc BlockPointerTL = TL.getAs<BlockPointerTypeLoc>())
132     return BlockPointerTL.getPointeeLoc().getUnqualifiedLoc();
133   if (MemberPointerTypeLoc MemberPointerTL = TL.getAs<MemberPointerTypeLoc>())
134     return MemberPointerTL.getPointeeLoc().getUnqualifiedLoc();
135   if (ElaboratedTypeLoc ETL = TL.getAs<ElaboratedTypeLoc>())
136     return ETL.getNamedTypeLoc();
137 
138   return TL;
139 }
140 
141 static bool getFunctionTypeLoc(TypeLoc TL, FunctionTypeLoc &ResFTL) {
142   TypeLoc PrevTL;
143   while (PrevTL != TL) {
144     PrevTL = TL;
145     TL = lookThroughTypedefOrTypeAliasLocs(TL);
146   }
147 
148   if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {
149     ResFTL = FTL;
150     return true;
151   }
152 
153   if (TemplateSpecializationTypeLoc STL =
154           TL.getAs<TemplateSpecializationTypeLoc>()) {
155     // If we have a typedef to a template specialization with exactly one
156     // template argument of a function type, this looks like std::function,
157     // boost::function, or other function wrapper.  Treat these typedefs as
158     // functions.
159     if (STL.getNumArgs() != 1)
160       return false;
161     TemplateArgumentLoc MaybeFunction = STL.getArgLoc(0);
162     if (MaybeFunction.getArgument().getKind() != TemplateArgument::Type)
163       return false;
164     TypeSourceInfo *MaybeFunctionTSI = MaybeFunction.getTypeSourceInfo();
165     TypeLoc TL = MaybeFunctionTSI->getTypeLoc().getUnqualifiedLoc();
166     if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {
167       ResFTL = FTL;
168       return true;
169     }
170   }
171 
172   return false;
173 }
174 
175 const char *ParamCommandComment::getDirectionAsString(PassDirection D) {
176   switch (D) {
177   case ParamCommandComment::In:
178     return "[in]";
179   case ParamCommandComment::Out:
180     return "[out]";
181   case ParamCommandComment::InOut:
182     return "[in,out]";
183   }
184   llvm_unreachable("unknown PassDirection");
185 }
186 
187 void DeclInfo::fill() {
188   assert(!IsFilled);
189 
190   // Set defaults.
191   Kind = OtherKind;
192   TemplateKind = NotTemplate;
193   IsObjCMethod = false;
194   IsInstanceMethod = false;
195   IsClassMethod = false;
196   ParamVars = None;
197   TemplateParameters = nullptr;
198 
199   if (!CommentDecl) {
200     // If there is no declaration, the defaults is our only guess.
201     IsFilled = true;
202     return;
203   }
204   CurrentDecl = CommentDecl;
205 
206   Decl::Kind K = CommentDecl->getKind();
207   switch (K) {
208   default:
209     // Defaults are should be good for declarations we don't handle explicitly.
210     break;
211   case Decl::Function:
212   case Decl::CXXMethod:
213   case Decl::CXXConstructor:
214   case Decl::CXXDestructor:
215   case Decl::CXXConversion: {
216     const FunctionDecl *FD = cast<FunctionDecl>(CommentDecl);
217     Kind = FunctionKind;
218     ParamVars = FD->parameters();
219     ReturnType = FD->getReturnType();
220     unsigned NumLists = FD->getNumTemplateParameterLists();
221     if (NumLists != 0) {
222       TemplateKind = TemplateSpecialization;
223       TemplateParameters =
224           FD->getTemplateParameterList(NumLists - 1);
225     }
226 
227     if (K == Decl::CXXMethod || K == Decl::CXXConstructor ||
228         K == Decl::CXXDestructor || K == Decl::CXXConversion) {
229       const CXXMethodDecl *MD = cast<CXXMethodDecl>(CommentDecl);
230       IsInstanceMethod = MD->isInstance();
231       IsClassMethod = !IsInstanceMethod;
232     }
233     break;
234   }
235   case Decl::ObjCMethod: {
236     const ObjCMethodDecl *MD = cast<ObjCMethodDecl>(CommentDecl);
237     Kind = FunctionKind;
238     ParamVars = MD->parameters();
239     ReturnType = MD->getReturnType();
240     IsObjCMethod = true;
241     IsInstanceMethod = MD->isInstanceMethod();
242     IsClassMethod = !IsInstanceMethod;
243     break;
244   }
245   case Decl::FunctionTemplate: {
246     const FunctionTemplateDecl *FTD = cast<FunctionTemplateDecl>(CommentDecl);
247     Kind = FunctionKind;
248     TemplateKind = Template;
249     const FunctionDecl *FD = FTD->getTemplatedDecl();
250     ParamVars = FD->parameters();
251     ReturnType = FD->getReturnType();
252     TemplateParameters = FTD->getTemplateParameters();
253     break;
254   }
255   case Decl::ClassTemplate: {
256     const ClassTemplateDecl *CTD = cast<ClassTemplateDecl>(CommentDecl);
257     Kind = ClassKind;
258     TemplateKind = Template;
259     TemplateParameters = CTD->getTemplateParameters();
260     break;
261   }
262   case Decl::ClassTemplatePartialSpecialization: {
263     const ClassTemplatePartialSpecializationDecl *CTPSD =
264         cast<ClassTemplatePartialSpecializationDecl>(CommentDecl);
265     Kind = ClassKind;
266     TemplateKind = TemplatePartialSpecialization;
267     TemplateParameters = CTPSD->getTemplateParameters();
268     break;
269   }
270   case Decl::ClassTemplateSpecialization:
271     Kind = ClassKind;
272     TemplateKind = TemplateSpecialization;
273     break;
274   case Decl::Record:
275   case Decl::CXXRecord:
276     Kind = ClassKind;
277     break;
278   case Decl::Var:
279   case Decl::Field:
280   case Decl::EnumConstant:
281   case Decl::ObjCIvar:
282   case Decl::ObjCAtDefsField:
283     Kind = VariableKind;
284     break;
285   case Decl::Namespace:
286     Kind = NamespaceKind;
287     break;
288   case Decl::TypeAlias:
289   case Decl::Typedef: {
290     Kind = TypedefKind;
291     // If this is a typedef / using to something we consider a function, extract
292     // arguments and return type.
293     const TypeSourceInfo *TSI =
294         K == Decl::Typedef
295             ? cast<TypedefDecl>(CommentDecl)->getTypeSourceInfo()
296             : cast<TypeAliasDecl>(CommentDecl)->getTypeSourceInfo();
297     if (!TSI)
298       break;
299     TypeLoc TL = TSI->getTypeLoc().getUnqualifiedLoc();
300     FunctionTypeLoc FTL;
301     if (getFunctionTypeLoc(TL, FTL)) {
302       Kind = FunctionKind;
303       ParamVars = FTL.getParams();
304       ReturnType = FTL.getReturnLoc().getType();
305     }
306     break;
307   }
308   case Decl::TypeAliasTemplate: {
309     const TypeAliasTemplateDecl *TAT = cast<TypeAliasTemplateDecl>(CommentDecl);
310     Kind = TypedefKind;
311     TemplateKind = Template;
312     TemplateParameters = TAT->getTemplateParameters();
313     TypeAliasDecl *TAD = TAT->getTemplatedDecl();
314     if (!TAD)
315       break;
316 
317     const TypeSourceInfo *TSI = TAD->getTypeSourceInfo();
318     if (!TSI)
319       break;
320     TypeLoc TL = TSI->getTypeLoc().getUnqualifiedLoc();
321     FunctionTypeLoc FTL;
322     if (getFunctionTypeLoc(TL, FTL)) {
323       Kind = FunctionKind;
324       ParamVars = FTL.getParams();
325       ReturnType = FTL.getReturnLoc().getType();
326     }
327     break;
328   }
329   case Decl::Enum:
330     Kind = EnumKind;
331     break;
332   }
333 
334   IsFilled = true;
335 }
336 
337 StringRef ParamCommandComment::getParamName(const FullComment *FC) const {
338   assert(isParamIndexValid());
339   if (isVarArgParam())
340     return "...";
341   return FC->getDeclInfo()->ParamVars[getParamIndex()]->getName();
342 }
343 
344 StringRef TParamCommandComment::getParamName(const FullComment *FC) const {
345   assert(isPositionValid());
346   const TemplateParameterList *TPL = FC->getDeclInfo()->TemplateParameters;
347   for (unsigned i = 0, e = getDepth(); i != e; ++i) {
348     if (i == e-1)
349       return TPL->getParam(getIndex(i))->getName();
350     const NamedDecl *Param = TPL->getParam(getIndex(i));
351     if (const TemplateTemplateParmDecl *TTP =
352           dyn_cast<TemplateTemplateParmDecl>(Param))
353       TPL = TTP->getTemplateParameters();
354   }
355   return "";
356 }
357 
358 } // end namespace comments
359 } // end namespace clang
360 
361