1 //===--- ASTDiagnostic.cpp - Diagnostic Printing Hooks for AST Nodes ------===// 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 a diagnostic formatting hook for AST elements. 11 // 12 //===----------------------------------------------------------------------===// 13 #include "clang/AST/ASTDiagnostic.h" 14 15 #include "clang/AST/ASTContext.h" 16 #include "clang/AST/DeclObjC.h" 17 #include "clang/AST/Type.h" 18 #include "llvm/Support/raw_ostream.h" 19 20 using namespace clang; 21 22 // Returns a desugared version of the QualType, and marks ShouldAKA as true 23 // whenever we remove significant sugar from the type. 24 static QualType Desugar(ASTContext &Context, QualType QT, bool &ShouldAKA) { 25 QualifierCollector QC; 26 27 while (true) { 28 const Type *Ty = QC.strip(QT); 29 30 // Don't aka just because we saw an elaborated type... 31 if (const ElaboratedType *ET = dyn_cast<ElaboratedType>(Ty)) { 32 QT = ET->desugar(); 33 continue; 34 } 35 // ... or a paren type ... 36 if (const ParenType *PT = dyn_cast<ParenType>(Ty)) { 37 QT = PT->desugar(); 38 continue; 39 } 40 // ...or a substituted template type parameter ... 41 if (const SubstTemplateTypeParmType *ST = 42 dyn_cast<SubstTemplateTypeParmType>(Ty)) { 43 QT = ST->desugar(); 44 continue; 45 } 46 // ...or an attributed type... 47 if (const AttributedType *AT = dyn_cast<AttributedType>(Ty)) { 48 QT = AT->desugar(); 49 continue; 50 } 51 // ... or an auto type. 52 if (const AutoType *AT = dyn_cast<AutoType>(Ty)) { 53 if (!AT->isSugared()) 54 break; 55 QT = AT->desugar(); 56 continue; 57 } 58 59 // Don't desugar template specializations, unless it's an alias template. 60 if (const TemplateSpecializationType *TST 61 = dyn_cast<TemplateSpecializationType>(Ty)) 62 if (!TST->isTypeAlias()) 63 break; 64 65 // Don't desugar magic Objective-C types. 66 if (QualType(Ty,0) == Context.getObjCIdType() || 67 QualType(Ty,0) == Context.getObjCClassType() || 68 QualType(Ty,0) == Context.getObjCSelType() || 69 QualType(Ty,0) == Context.getObjCProtoType()) 70 break; 71 72 // Don't desugar va_list. 73 if (QualType(Ty,0) == Context.getBuiltinVaListType()) 74 break; 75 76 // Otherwise, do a single-step desugar. 77 QualType Underlying; 78 bool IsSugar = false; 79 switch (Ty->getTypeClass()) { 80 #define ABSTRACT_TYPE(Class, Base) 81 #define TYPE(Class, Base) \ 82 case Type::Class: { \ 83 const Class##Type *CTy = cast<Class##Type>(Ty); \ 84 if (CTy->isSugared()) { \ 85 IsSugar = true; \ 86 Underlying = CTy->desugar(); \ 87 } \ 88 break; \ 89 } 90 #include "clang/AST/TypeNodes.def" 91 } 92 93 // If it wasn't sugared, we're done. 94 if (!IsSugar) 95 break; 96 97 // If the desugared type is a vector type, we don't want to expand 98 // it, it will turn into an attribute mess. People want their "vec4". 99 if (isa<VectorType>(Underlying)) 100 break; 101 102 // Don't desugar through the primary typedef of an anonymous type. 103 if (const TagType *UTT = Underlying->getAs<TagType>()) 104 if (const TypedefType *QTT = dyn_cast<TypedefType>(QT)) 105 if (UTT->getDecl()->getTypedefNameForAnonDecl() == QTT->getDecl()) 106 break; 107 108 // Record that we actually looked through an opaque type here. 109 ShouldAKA = true; 110 QT = Underlying; 111 } 112 113 // If we have a pointer-like type, desugar the pointee as well. 114 // FIXME: Handle other pointer-like types. 115 if (const PointerType *Ty = QT->getAs<PointerType>()) { 116 QT = Context.getPointerType(Desugar(Context, Ty->getPointeeType(), 117 ShouldAKA)); 118 } else if (const LValueReferenceType *Ty = QT->getAs<LValueReferenceType>()) { 119 QT = Context.getLValueReferenceType(Desugar(Context, Ty->getPointeeType(), 120 ShouldAKA)); 121 } else if (const RValueReferenceType *Ty = QT->getAs<RValueReferenceType>()) { 122 QT = Context.getRValueReferenceType(Desugar(Context, Ty->getPointeeType(), 123 ShouldAKA)); 124 } 125 126 return QC.apply(Context, QT); 127 } 128 129 /// \brief Convert the given type to a string suitable for printing as part of 130 /// a diagnostic. 131 /// 132 /// There are four main criteria when determining whether we should have an 133 /// a.k.a. clause when pretty-printing a type: 134 /// 135 /// 1) Some types provide very minimal sugar that doesn't impede the 136 /// user's understanding --- for example, elaborated type 137 /// specifiers. If this is all the sugar we see, we don't want an 138 /// a.k.a. clause. 139 /// 2) Some types are technically sugared but are much more familiar 140 /// when seen in their sugared form --- for example, va_list, 141 /// vector types, and the magic Objective C types. We don't 142 /// want to desugar these, even if we do produce an a.k.a. clause. 143 /// 3) Some types may have already been desugared previously in this diagnostic. 144 /// if this is the case, doing another "aka" would just be clutter. 145 /// 4) Two different types within the same diagnostic have the same output 146 /// string. In this case, force an a.k.a with the desugared type when 147 /// doing so will provide additional information. 148 /// 149 /// \param Context the context in which the type was allocated 150 /// \param Ty the type to print 151 /// \param QualTypeVals pointer values to QualTypes which are used in the 152 /// diagnostic message 153 static std::string 154 ConvertTypeToDiagnosticString(ASTContext &Context, QualType Ty, 155 const DiagnosticsEngine::ArgumentValue *PrevArgs, 156 unsigned NumPrevArgs, 157 SmallVectorImpl<intptr_t> &QualTypeVals) { 158 // FIXME: Playing with std::string is really slow. 159 bool ForceAKA = false; 160 QualType CanTy = Ty.getCanonicalType(); 161 std::string S = Ty.getAsString(Context.getPrintingPolicy()); 162 std::string CanS = CanTy.getAsString(Context.getPrintingPolicy()); 163 164 for (SmallVectorImpl<intptr_t>::iterator I = QualTypeVals.begin(), 165 E = QualTypeVals.end(); I != E; ++I) { 166 QualType CompareTy = 167 QualType::getFromOpaquePtr(reinterpret_cast<void*>(*I)); 168 if (CompareTy == Ty) 169 continue; // Same types 170 QualType CompareCanTy = CompareTy.getCanonicalType(); 171 if (CompareCanTy == CanTy) 172 continue; // Same canonical types 173 std::string CompareS = CompareTy.getAsString(Context.getPrintingPolicy()); 174 if (CompareS != S) 175 continue; // Original strings are different 176 std::string CompareCanS = CompareCanTy.getAsString(Context.getPrintingPolicy()); 177 if (CompareCanS == CanS) 178 continue; // No new info from canonical type 179 180 ForceAKA = true; 181 break; 182 } 183 184 // Check to see if we already desugared this type in this 185 // diagnostic. If so, don't do it again. 186 bool Repeated = false; 187 for (unsigned i = 0; i != NumPrevArgs; ++i) { 188 // TODO: Handle ak_declcontext case. 189 if (PrevArgs[i].first == DiagnosticsEngine::ak_qualtype) { 190 void *Ptr = (void*)PrevArgs[i].second; 191 QualType PrevTy(QualType::getFromOpaquePtr(Ptr)); 192 if (PrevTy == Ty) { 193 Repeated = true; 194 break; 195 } 196 } 197 } 198 199 // Consider producing an a.k.a. clause if removing all the direct 200 // sugar gives us something "significantly different". 201 if (!Repeated) { 202 bool ShouldAKA = false; 203 QualType DesugaredTy = Desugar(Context, Ty, ShouldAKA); 204 if (ShouldAKA || ForceAKA) { 205 if (DesugaredTy == Ty) { 206 DesugaredTy = Ty.getCanonicalType(); 207 } 208 std::string akaStr = DesugaredTy.getAsString(Context.getPrintingPolicy()); 209 if (akaStr != S) { 210 S = "'" + S + "' (aka '" + akaStr + "')"; 211 return S; 212 } 213 } 214 } 215 216 S = "'" + S + "'"; 217 return S; 218 } 219 220 void clang::FormatASTNodeDiagnosticArgument( 221 DiagnosticsEngine::ArgumentKind Kind, 222 intptr_t Val, 223 const char *Modifier, 224 unsigned ModLen, 225 const char *Argument, 226 unsigned ArgLen, 227 const DiagnosticsEngine::ArgumentValue *PrevArgs, 228 unsigned NumPrevArgs, 229 SmallVectorImpl<char> &Output, 230 void *Cookie, 231 SmallVectorImpl<intptr_t> &QualTypeVals) { 232 ASTContext &Context = *static_cast<ASTContext*>(Cookie); 233 234 std::string S; 235 bool NeedQuotes = true; 236 237 switch (Kind) { 238 default: llvm_unreachable("unknown ArgumentKind"); 239 case DiagnosticsEngine::ak_qualtype: { 240 assert(ModLen == 0 && ArgLen == 0 && 241 "Invalid modifier for QualType argument"); 242 243 QualType Ty(QualType::getFromOpaquePtr(reinterpret_cast<void*>(Val))); 244 S = ConvertTypeToDiagnosticString(Context, Ty, PrevArgs, NumPrevArgs, 245 QualTypeVals); 246 NeedQuotes = false; 247 break; 248 } 249 case DiagnosticsEngine::ak_declarationname: { 250 DeclarationName N = DeclarationName::getFromOpaqueInteger(Val); 251 S = N.getAsString(); 252 253 if (ModLen == 9 && !memcmp(Modifier, "objcclass", 9) && ArgLen == 0) 254 S = '+' + S; 255 else if (ModLen == 12 && !memcmp(Modifier, "objcinstance", 12) 256 && ArgLen==0) 257 S = '-' + S; 258 else 259 assert(ModLen == 0 && ArgLen == 0 && 260 "Invalid modifier for DeclarationName argument"); 261 break; 262 } 263 case DiagnosticsEngine::ak_nameddecl: { 264 bool Qualified; 265 if (ModLen == 1 && Modifier[0] == 'q' && ArgLen == 0) 266 Qualified = true; 267 else { 268 assert(ModLen == 0 && ArgLen == 0 && 269 "Invalid modifier for NamedDecl* argument"); 270 Qualified = false; 271 } 272 const NamedDecl *ND = reinterpret_cast<const NamedDecl*>(Val); 273 ND->getNameForDiagnostic(S, Context.getPrintingPolicy(), Qualified); 274 break; 275 } 276 case DiagnosticsEngine::ak_nestednamespec: { 277 llvm::raw_string_ostream OS(S); 278 reinterpret_cast<NestedNameSpecifier*>(Val)->print(OS, 279 Context.getPrintingPolicy()); 280 NeedQuotes = false; 281 break; 282 } 283 case DiagnosticsEngine::ak_declcontext: { 284 DeclContext *DC = reinterpret_cast<DeclContext *> (Val); 285 assert(DC && "Should never have a null declaration context"); 286 287 if (DC->isTranslationUnit()) { 288 // FIXME: Get these strings from some localized place 289 if (Context.getLangOptions().CPlusPlus) 290 S = "the global namespace"; 291 else 292 S = "the global scope"; 293 } else if (TypeDecl *Type = dyn_cast<TypeDecl>(DC)) { 294 S = ConvertTypeToDiagnosticString(Context, 295 Context.getTypeDeclType(Type), 296 PrevArgs, NumPrevArgs, QualTypeVals); 297 } else { 298 // FIXME: Get these strings from some localized place 299 NamedDecl *ND = cast<NamedDecl>(DC); 300 if (isa<NamespaceDecl>(ND)) 301 S += "namespace "; 302 else if (isa<ObjCMethodDecl>(ND)) 303 S += "method "; 304 else if (isa<FunctionDecl>(ND)) 305 S += "function "; 306 307 S += "'"; 308 ND->getNameForDiagnostic(S, Context.getPrintingPolicy(), true); 309 S += "'"; 310 } 311 NeedQuotes = false; 312 break; 313 } 314 } 315 316 if (NeedQuotes) 317 Output.push_back('\''); 318 319 Output.append(S.begin(), S.end()); 320 321 if (NeedQuotes) 322 Output.push_back('\''); 323 } 324