ASTDiagnostic.cpp revision 3e4c6c4c79a03f5cb0c4671d7c282d623c6dc35e
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 20using 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. 24static 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) \ 82case Type::Class: { \ 83const Class##Type *CTy = cast<Class##Type>(Ty); \ 84if (CTy->isSugared()) { \ 85IsSugar = true; \ 86Underlying = CTy->desugar(); \ 87} \ 88break; \ 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 three 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/// 146/// \param Context the context in which the type was allocated 147/// \param Ty the type to print 148static std::string 149ConvertTypeToDiagnosticString(ASTContext &Context, QualType Ty, 150 const Diagnostic::ArgumentValue *PrevArgs, 151 unsigned NumPrevArgs) { 152 // FIXME: Playing with std::string is really slow. 153 std::string S = Ty.getAsString(Context.PrintingPolicy); 154 155 // Check to see if we already desugared this type in this 156 // diagnostic. If so, don't do it again. 157 bool Repeated = false; 158 for (unsigned i = 0; i != NumPrevArgs; ++i) { 159 // TODO: Handle ak_declcontext case. 160 if (PrevArgs[i].first == Diagnostic::ak_qualtype) { 161 void *Ptr = (void*)PrevArgs[i].second; 162 QualType PrevTy(QualType::getFromOpaquePtr(Ptr)); 163 if (PrevTy == Ty) { 164 Repeated = true; 165 break; 166 } 167 } 168 } 169 170 // Consider producing an a.k.a. clause if removing all the direct 171 // sugar gives us something "significantly different". 172 if (!Repeated) { 173 bool ShouldAKA = false; 174 QualType DesugaredTy = Desugar(Context, Ty, ShouldAKA); 175 if (ShouldAKA) { 176 S = "'" + S + "' (aka '"; 177 S += DesugaredTy.getAsString(Context.PrintingPolicy); 178 S += "')"; 179 return S; 180 } 181 } 182 183 S = "'" + S + "'"; 184 return S; 185} 186 187void clang::FormatASTNodeDiagnosticArgument(Diagnostic::ArgumentKind Kind, 188 intptr_t Val, 189 const char *Modifier, 190 unsigned ModLen, 191 const char *Argument, 192 unsigned ArgLen, 193 const Diagnostic::ArgumentValue *PrevArgs, 194 unsigned NumPrevArgs, 195 llvm::SmallVectorImpl<char> &Output, 196 void *Cookie) { 197 ASTContext &Context = *static_cast<ASTContext*>(Cookie); 198 199 std::string S; 200 bool NeedQuotes = true; 201 202 switch (Kind) { 203 default: assert(0 && "unknown ArgumentKind"); 204 case Diagnostic::ak_qualtype: { 205 assert(ModLen == 0 && ArgLen == 0 && 206 "Invalid modifier for QualType argument"); 207 208 QualType Ty(QualType::getFromOpaquePtr(reinterpret_cast<void*>(Val))); 209 S = ConvertTypeToDiagnosticString(Context, Ty, PrevArgs, NumPrevArgs); 210 NeedQuotes = false; 211 break; 212 } 213 case Diagnostic::ak_declarationname: { 214 DeclarationName N = DeclarationName::getFromOpaqueInteger(Val); 215 S = N.getAsString(); 216 217 if (ModLen == 9 && !memcmp(Modifier, "objcclass", 9) && ArgLen == 0) 218 S = '+' + S; 219 else if (ModLen == 12 && !memcmp(Modifier, "objcinstance", 12) 220 && ArgLen==0) 221 S = '-' + S; 222 else 223 assert(ModLen == 0 && ArgLen == 0 && 224 "Invalid modifier for DeclarationName argument"); 225 break; 226 } 227 case Diagnostic::ak_nameddecl: { 228 bool Qualified; 229 if (ModLen == 1 && Modifier[0] == 'q' && ArgLen == 0) 230 Qualified = true; 231 else { 232 assert(ModLen == 0 && ArgLen == 0 && 233 "Invalid modifier for NamedDecl* argument"); 234 Qualified = false; 235 } 236 reinterpret_cast<NamedDecl*>(Val)-> 237 getNameForDiagnostic(S, Context.PrintingPolicy, Qualified); 238 break; 239 } 240 case Diagnostic::ak_nestednamespec: { 241 llvm::raw_string_ostream OS(S); 242 reinterpret_cast<NestedNameSpecifier*>(Val)->print(OS, 243 Context.PrintingPolicy); 244 NeedQuotes = false; 245 break; 246 } 247 case Diagnostic::ak_declcontext: { 248 DeclContext *DC = reinterpret_cast<DeclContext *> (Val); 249 assert(DC && "Should never have a null declaration context"); 250 251 if (DC->isTranslationUnit()) { 252 // FIXME: Get these strings from some localized place 253 if (Context.getLangOptions().CPlusPlus) 254 S = "the global namespace"; 255 else 256 S = "the global scope"; 257 } else if (TypeDecl *Type = dyn_cast<TypeDecl>(DC)) { 258 S = ConvertTypeToDiagnosticString(Context, 259 Context.getTypeDeclType(Type), 260 PrevArgs, NumPrevArgs); 261 } else { 262 // FIXME: Get these strings from some localized place 263 NamedDecl *ND = cast<NamedDecl>(DC); 264 if (isa<NamespaceDecl>(ND)) 265 S += "namespace "; 266 else if (isa<ObjCMethodDecl>(ND)) 267 S += "method "; 268 else if (isa<FunctionDecl>(ND)) 269 S += "function "; 270 271 S += "'"; 272 ND->getNameForDiagnostic(S, Context.PrintingPolicy, true); 273 S += "'"; 274 } 275 NeedQuotes = false; 276 break; 277 } 278 } 279 280 if (NeedQuotes) 281 Output.push_back('\''); 282 283 Output.append(S.begin(), S.end()); 284 285 if (NeedQuotes) 286 Output.push_back('\''); 287} 288