1//===--- Comment.cpp - Comment 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#include "clang/AST/Comment.h"
10#include "clang/AST/ASTContext.h"
11#include "clang/AST/Decl.h"
12#include "clang/AST/DeclObjC.h"
13#include "clang/AST/DeclTemplate.h"
14#include "clang/Basic/CharInfo.h"
15#include "llvm/Support/ErrorHandling.h"
16#include <type_traits>
17
18namespace clang {
19namespace comments {
20
21// Check that no comment class has a non-trival destructor. They are allocated
22// with a BumpPtrAllocator and therefore their destructor is not executed.
23#define ABSTRACT_COMMENT(COMMENT)
24#define COMMENT(CLASS, PARENT) \
25 static_assert(std::is_trivially_destructible<CLASS>::value, \
26 #CLASS " should be trivially destructible!");
27#include "clang/AST/CommentNodes.inc"
28#undef COMMENT
29#undef ABSTRACT_COMMENT
30
31// DeclInfo is also allocated with a BumpPtrAllocator.
32static_assert(std::is_trivially_destructible_v<DeclInfo>,
33 "DeclInfo should be trivially destructible!");
34
35const char *Comment::getCommentKindName() const {
36 switch (getCommentKind()) {
37 case CommentKind::None:
38 return "None";
39#define ABSTRACT_COMMENT(COMMENT)
40#define COMMENT(CLASS, PARENT) \
41 case CommentKind::CLASS: \
42 return #CLASS;
43#include "clang/AST/CommentNodes.inc"
44#undef COMMENT
45#undef ABSTRACT_COMMENT
46 }
47 llvm_unreachable("Unknown comment kind!");
48}
49
50namespace {
51struct good {};
52struct bad {};
53
54template <typename T>
55good implements_child_begin_end(Comment::child_iterator (T::*)() const) {
56 return good();
57}
58
59LLVM_ATTRIBUTE_UNUSED
60static inline bad implements_child_begin_end(
61 Comment::child_iterator (Comment::*)() const) {
62 return bad();
63}
64
65#define ASSERT_IMPLEMENTS_child_begin(function) \
66 (void) good(implements_child_begin_end(function))
67
68LLVM_ATTRIBUTE_UNUSED
69static inline void CheckCommentASTNodes() {
70#define ABSTRACT_COMMENT(COMMENT)
71#define COMMENT(CLASS, PARENT) \
72 ASSERT_IMPLEMENTS_child_begin(&CLASS::child_begin); \
73 ASSERT_IMPLEMENTS_child_begin(&CLASS::child_end);
74#include "clang/AST/CommentNodes.inc"
75#undef COMMENT
76#undef ABSTRACT_COMMENT
77}
78
79#undef ASSERT_IMPLEMENTS_child_begin
80
81} // end unnamed namespace
82
83Comment::child_iterator Comment::child_begin() const {
84 switch (getCommentKind()) {
85 case CommentKind::None:
86 llvm_unreachable("comment without a kind");
87#define ABSTRACT_COMMENT(COMMENT)
88#define COMMENT(CLASS, PARENT) \
89 case CommentKind::CLASS: \
90 return static_cast<const CLASS *>(this)->child_begin();
91#include "clang/AST/CommentNodes.inc"
92#undef COMMENT
93#undef ABSTRACT_COMMENT
94 }
95 llvm_unreachable("Unknown comment kind!");
96}
97
98Comment::child_iterator Comment::child_end() const {
99 switch (getCommentKind()) {
100 case CommentKind::None:
101 llvm_unreachable("comment without a kind");
102#define ABSTRACT_COMMENT(COMMENT)
103#define COMMENT(CLASS, PARENT) \
104 case CommentKind::CLASS: \
105 return static_cast<const CLASS *>(this)->child_end();
106#include "clang/AST/CommentNodes.inc"
107#undef COMMENT
108#undef ABSTRACT_COMMENT
109 }
110 llvm_unreachable("Unknown comment kind!");
111}
112
113bool TextComment::isWhitespaceNoCache() const {
114 return llvm::all_of(Text, clang::isWhitespace);
115}
116
117bool ParagraphComment::isWhitespaceNoCache() const {
118 for (child_iterator I = child_begin(), E = child_end(); I != E; ++I) {
119 if (const TextComment *TC = dyn_cast<TextComment>(*I)) {
120 if (!TC->isWhitespace())
121 return false;
122 } else
123 return false;
124 }
125 return true;
126}
127
128static TypeLoc lookThroughTypedefOrTypeAliasLocs(TypeLoc &SrcTL) {
129 TypeLoc TL = SrcTL.IgnoreParens();
130
131 // Look through attribute types.
132 if (AttributedTypeLoc AttributeTL = TL.getAs<AttributedTypeLoc>())
133 return AttributeTL.getModifiedLoc();
134 // Look through qualified types.
135 if (QualifiedTypeLoc QualifiedTL = TL.getAs<QualifiedTypeLoc>())
136 return QualifiedTL.getUnqualifiedLoc();
137 // Look through pointer types.
138 if (PointerTypeLoc PointerTL = TL.getAs<PointerTypeLoc>())
139 return PointerTL.getPointeeLoc().getUnqualifiedLoc();
140 // Look through reference types.
141 if (ReferenceTypeLoc ReferenceTL = TL.getAs<ReferenceTypeLoc>())
142 return ReferenceTL.getPointeeLoc().getUnqualifiedLoc();
143 // Look through adjusted types.
144 if (AdjustedTypeLoc ATL = TL.getAs<AdjustedTypeLoc>())
145 return ATL.getOriginalLoc();
146 if (BlockPointerTypeLoc BlockPointerTL = TL.getAs<BlockPointerTypeLoc>())
147 return BlockPointerTL.getPointeeLoc().getUnqualifiedLoc();
148 if (MemberPointerTypeLoc MemberPointerTL = TL.getAs<MemberPointerTypeLoc>())
149 return MemberPointerTL.getPointeeLoc().getUnqualifiedLoc();
150 if (ElaboratedTypeLoc ETL = TL.getAs<ElaboratedTypeLoc>())
151 return ETL.getNamedTypeLoc();
152
153 return TL;
154}
155
156static bool getFunctionTypeLoc(TypeLoc TL, FunctionTypeLoc &ResFTL) {
157 TypeLoc PrevTL;
158 while (PrevTL != TL) {
159 PrevTL = TL;
160 TL = lookThroughTypedefOrTypeAliasLocs(SrcTL&: TL);
161 }
162
163 if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {
164 ResFTL = FTL;
165 return true;
166 }
167
168 if (TemplateSpecializationTypeLoc STL =
169 TL.getAs<TemplateSpecializationTypeLoc>()) {
170 // If we have a typedef to a template specialization with exactly one
171 // template argument of a function type, this looks like std::function,
172 // boost::function, or other function wrapper. Treat these typedefs as
173 // functions.
174 if (STL.getNumArgs() != 1)
175 return false;
176 TemplateArgumentLoc MaybeFunction = STL.getArgLoc(i: 0);
177 if (MaybeFunction.getArgument().getKind() != TemplateArgument::Type)
178 return false;
179 TypeSourceInfo *MaybeFunctionTSI = MaybeFunction.getTypeSourceInfo();
180 TypeLoc TL = MaybeFunctionTSI->getTypeLoc().getUnqualifiedLoc();
181 if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {
182 ResFTL = FTL;
183 return true;
184 }
185 }
186
187 return false;
188}
189
190const char *
191ParamCommandComment::getDirectionAsString(ParamCommandPassDirection D) {
192 switch (D) {
193 case ParamCommandPassDirection::In:
194 return "[in]";
195 case ParamCommandPassDirection::Out:
196 return "[out]";
197 case ParamCommandPassDirection::InOut:
198 return "[in,out]";
199 }
200 llvm_unreachable("unknown PassDirection");
201}
202
203void DeclInfo::fill() {
204 assert(!IsFilled);
205
206 // Set defaults.
207 Kind = OtherKind;
208 TemplateKind = NotTemplate;
209 IsObjCMethod = false;
210 IsInstanceMethod = false;
211 IsClassMethod = false;
212 IsVariadic = false;
213 ParamVars = std::nullopt;
214 TemplateParameters = nullptr;
215
216 if (!CommentDecl) {
217 // If there is no declaration, the defaults is our only guess.
218 IsFilled = true;
219 return;
220 }
221 CurrentDecl = CommentDecl;
222
223 Decl::Kind K = CommentDecl->getKind();
224 const TypeSourceInfo *TSI = nullptr;
225 switch (K) {
226 default:
227 // Defaults are should be good for declarations we don't handle explicitly.
228 break;
229 case Decl::Function:
230 case Decl::CXXMethod:
231 case Decl::CXXConstructor:
232 case Decl::CXXDestructor:
233 case Decl::CXXConversion: {
234 const FunctionDecl *FD = cast<FunctionDecl>(CommentDecl);
235 Kind = FunctionKind;
236 ParamVars = FD->parameters();
237 ReturnType = FD->getReturnType();
238 unsigned NumLists = FD->getNumTemplateParameterLists();
239 if (NumLists != 0) {
240 TemplateKind = TemplateSpecialization;
241 TemplateParameters =
242 FD->getTemplateParameterList(NumLists - 1);
243 }
244
245 if (K == Decl::CXXMethod || K == Decl::CXXConstructor ||
246 K == Decl::CXXDestructor || K == Decl::CXXConversion) {
247 const CXXMethodDecl *MD = cast<CXXMethodDecl>(CommentDecl);
248 IsInstanceMethod = MD->isInstance();
249 IsClassMethod = !IsInstanceMethod;
250 }
251 IsVariadic = FD->isVariadic();
252 assert(involvesFunctionType());
253 break;
254 }
255 case Decl::ObjCMethod: {
256 const ObjCMethodDecl *MD = cast<ObjCMethodDecl>(CommentDecl);
257 Kind = FunctionKind;
258 ParamVars = MD->parameters();
259 ReturnType = MD->getReturnType();
260 IsObjCMethod = true;
261 IsInstanceMethod = MD->isInstanceMethod();
262 IsClassMethod = !IsInstanceMethod;
263 IsVariadic = MD->isVariadic();
264 assert(involvesFunctionType());
265 break;
266 }
267 case Decl::FunctionTemplate: {
268 const FunctionTemplateDecl *FTD = cast<FunctionTemplateDecl>(CommentDecl);
269 Kind = FunctionKind;
270 TemplateKind = Template;
271 const FunctionDecl *FD = FTD->getTemplatedDecl();
272 ParamVars = FD->parameters();
273 ReturnType = FD->getReturnType();
274 TemplateParameters = FTD->getTemplateParameters();
275 IsVariadic = FD->isVariadic();
276 assert(involvesFunctionType());
277 break;
278 }
279 case Decl::ClassTemplate: {
280 const ClassTemplateDecl *CTD = cast<ClassTemplateDecl>(CommentDecl);
281 Kind = ClassKind;
282 TemplateKind = Template;
283 TemplateParameters = CTD->getTemplateParameters();
284 break;
285 }
286 case Decl::ClassTemplatePartialSpecialization: {
287 const ClassTemplatePartialSpecializationDecl *CTPSD =
288 cast<ClassTemplatePartialSpecializationDecl>(CommentDecl);
289 Kind = ClassKind;
290 TemplateKind = TemplatePartialSpecialization;
291 TemplateParameters = CTPSD->getTemplateParameters();
292 break;
293 }
294 case Decl::ClassTemplateSpecialization:
295 Kind = ClassKind;
296 TemplateKind = TemplateSpecialization;
297 break;
298 case Decl::Record:
299 case Decl::CXXRecord:
300 Kind = ClassKind;
301 break;
302 case Decl::Var:
303 if (const VarTemplateDecl *VTD =
304 cast<VarDecl>(CommentDecl)->getDescribedVarTemplate()) {
305 TemplateKind = TemplateSpecialization;
306 TemplateParameters = VTD->getTemplateParameters();
307 }
308 [[fallthrough]];
309 case Decl::Field:
310 case Decl::EnumConstant:
311 case Decl::ObjCIvar:
312 case Decl::ObjCAtDefsField:
313 case Decl::ObjCProperty:
314 if (const auto *VD = dyn_cast<DeclaratorDecl>(CommentDecl))
315 TSI = VD->getTypeSourceInfo();
316 else if (const auto *PD = dyn_cast<ObjCPropertyDecl>(CommentDecl))
317 TSI = PD->getTypeSourceInfo();
318 Kind = VariableKind;
319 break;
320 case Decl::VarTemplate: {
321 const VarTemplateDecl *VTD = cast<VarTemplateDecl>(CommentDecl);
322 Kind = VariableKind;
323 TemplateKind = Template;
324 TemplateParameters = VTD->getTemplateParameters();
325 if (const VarDecl *VD = VTD->getTemplatedDecl())
326 TSI = VD->getTypeSourceInfo();
327 break;
328 }
329 case Decl::Namespace:
330 Kind = NamespaceKind;
331 break;
332 case Decl::TypeAlias:
333 case Decl::Typedef:
334 Kind = TypedefKind;
335 TSI = cast<TypedefNameDecl>(CommentDecl)->getTypeSourceInfo();
336 break;
337 case Decl::TypeAliasTemplate: {
338 const TypeAliasTemplateDecl *TAT = cast<TypeAliasTemplateDecl>(CommentDecl);
339 Kind = TypedefKind;
340 TemplateKind = Template;
341 TemplateParameters = TAT->getTemplateParameters();
342 if (TypeAliasDecl *TAD = TAT->getTemplatedDecl())
343 TSI = TAD->getTypeSourceInfo();
344 break;
345 }
346 case Decl::Enum:
347 Kind = EnumKind;
348 break;
349 }
350
351 // If the type is a typedef / using to something we consider a function,
352 // extract arguments and return type.
353 if (TSI) {
354 TypeLoc TL = TSI->getTypeLoc().getUnqualifiedLoc();
355 FunctionTypeLoc FTL;
356 if (getFunctionTypeLoc(TL, ResFTL&: FTL)) {
357 ParamVars = FTL.getParams();
358 ReturnType = FTL.getReturnLoc().getType();
359 if (const auto *FPT = dyn_cast<FunctionProtoType>(FTL.getTypePtr()))
360 IsVariadic = FPT->isVariadic();
361 assert(involvesFunctionType());
362 }
363 }
364
365 IsFilled = true;
366}
367
368StringRef ParamCommandComment::getParamName(const FullComment *FC) const {
369 assert(isParamIndexValid());
370 if (isVarArgParam())
371 return "...";
372 return FC->getDeclInfo()->ParamVars[getParamIndex()]->getName();
373}
374
375StringRef TParamCommandComment::getParamName(const FullComment *FC) const {
376 assert(isPositionValid());
377 const TemplateParameterList *TPL = FC->getDeclInfo()->TemplateParameters;
378 for (unsigned i = 0, e = getDepth(); i != e; ++i) {
379 assert(TPL && "Unknown TemplateParameterList");
380 if (i == e - 1)
381 return TPL->getParam(Idx: getIndex(Depth: i))->getName();
382 const NamedDecl *Param = TPL->getParam(Idx: getIndex(Depth: i));
383 if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param))
384 TPL = TTP->getTemplateParameters();
385 }
386 return "";
387}
388
389} // end namespace comments
390} // end namespace clang
391
392

source code of clang/lib/AST/Comment.cpp