Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 1 | //===------- SemaTemplateVariadic.cpp - C++ Variadic Templates ------------===/ |
| 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 | // This file implements semantic analysis for C++0x variadic templates. |
| 10 | //===----------------------------------------------------------------------===/ |
| 11 | |
| 12 | #include "clang/Sema/Sema.h" |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 13 | #include "clang/Sema/ParsedTemplate.h" |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 14 | #include "clang/Sema/SemaInternal.h" |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 15 | #include "clang/Sema/Template.h" |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 16 | #include "clang/AST/Expr.h" |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 17 | #include "clang/AST/RecursiveASTVisitor.h" |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 18 | #include "clang/AST/TypeLoc.h" |
| 19 | |
| 20 | using namespace clang; |
| 21 | |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 22 | //---------------------------------------------------------------------------- |
| 23 | // Visitor that collects unexpanded parameter packs |
| 24 | //---------------------------------------------------------------------------- |
| 25 | |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 26 | namespace { |
| 27 | /// \brief A class that collects unexpanded parameter packs. |
| 28 | class CollectUnexpandedParameterPacksVisitor : |
| 29 | public RecursiveASTVisitor<CollectUnexpandedParameterPacksVisitor> |
| 30 | { |
| 31 | typedef RecursiveASTVisitor<CollectUnexpandedParameterPacksVisitor> |
| 32 | inherited; |
| 33 | |
| 34 | llvm::SmallVectorImpl<UnexpandedParameterPack> &Unexpanded; |
| 35 | |
| 36 | public: |
| 37 | explicit CollectUnexpandedParameterPacksVisitor( |
| 38 | llvm::SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) |
| 39 | : Unexpanded(Unexpanded) { } |
| 40 | |
| 41 | //------------------------------------------------------------------------ |
| 42 | // Recording occurrences of (unexpanded) parameter packs. |
| 43 | //------------------------------------------------------------------------ |
| 44 | |
| 45 | /// \brief Record occurrences of template type parameter packs. |
| 46 | bool VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) { |
| 47 | if (TL.getTypePtr()->isParameterPack()) |
| 48 | Unexpanded.push_back(std::make_pair(TL.getTypePtr(), TL.getNameLoc())); |
| 49 | return true; |
| 50 | } |
| 51 | |
| 52 | /// \brief Record occurrences of template type parameter packs |
| 53 | /// when we don't have proper source-location information for |
| 54 | /// them. |
| 55 | /// |
| 56 | /// Ideally, this routine would never be used. |
| 57 | bool VisitTemplateTypeParmType(TemplateTypeParmType *T) { |
| 58 | if (T->isParameterPack()) |
| 59 | Unexpanded.push_back(std::make_pair(T, SourceLocation())); |
| 60 | |
| 61 | return true; |
| 62 | } |
| 63 | |
| 64 | // FIXME: Record occurrences of non-type and template template |
| 65 | // parameter packs. |
| 66 | |
| 67 | // FIXME: Once we have pack expansions in the AST, block their |
| 68 | // traversal. |
| 69 | |
| 70 | //------------------------------------------------------------------------ |
| 71 | // Pruning the search for unexpanded parameter packs. |
| 72 | //------------------------------------------------------------------------ |
| 73 | |
| 74 | /// \brief Suppress traversal into statements and expressions that |
| 75 | /// do not contain unexpanded parameter packs. |
| 76 | bool TraverseStmt(Stmt *S) { |
| 77 | if (Expr *E = dyn_cast_or_null<Expr>(S)) |
| 78 | if (E->containsUnexpandedParameterPack()) |
| 79 | return inherited::TraverseStmt(E); |
| 80 | |
| 81 | return true; |
| 82 | } |
| 83 | |
| 84 | /// \brief Suppress traversal into types that do not contain |
| 85 | /// unexpanded parameter packs. |
| 86 | bool TraverseType(QualType T) { |
| 87 | if (!T.isNull() && T->containsUnexpandedParameterPack()) |
| 88 | return inherited::TraverseType(T); |
| 89 | |
| 90 | return true; |
| 91 | } |
| 92 | |
| 93 | /// \brief Suppress traversel into types with location information |
| 94 | /// that do not contain unexpanded parameter packs. |
| 95 | bool TraverseTypeLoc(TypeLoc TL) { |
| 96 | if (!TL.getType().isNull() && TL. |
| 97 | getType()->containsUnexpandedParameterPack()) |
| 98 | return inherited::TraverseTypeLoc(TL); |
| 99 | |
| 100 | return true; |
| 101 | } |
| 102 | |
Douglas Gregor | cff163e | 2010-12-15 21:57:59 +0000 | [diff] [blame] | 103 | /// \brief Suppress traversal of non-parameter declarations, since |
| 104 | /// they cannot contain unexpanded parameter packs. |
| 105 | bool TraverseDecl(Decl *D) { |
| 106 | if (D && isa<ParmVarDecl>(D)) |
| 107 | return inherited::TraverseDecl(D); |
| 108 | |
| 109 | return true; |
| 110 | } |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 111 | }; |
| 112 | } |
| 113 | |
| 114 | /// \brief Diagnose all of the unexpanded parameter packs in the given |
| 115 | /// vector. |
| 116 | static void |
| 117 | DiagnoseUnexpandedParameterPacks(Sema &S, SourceLocation Loc, |
| 118 | Sema::UnexpandedParameterPackContext UPPC, |
| 119 | const llvm::SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) { |
| 120 | llvm::SmallVector<SourceLocation, 4> Locations; |
| 121 | llvm::SmallVector<IdentifierInfo *, 4> Names; |
| 122 | llvm::SmallPtrSet<IdentifierInfo *, 4> NamesKnown; |
| 123 | |
| 124 | for (unsigned I = 0, N = Unexpanded.size(); I != N; ++I) { |
| 125 | IdentifierInfo *Name = 0; |
| 126 | if (const TemplateTypeParmType *TTP |
| 127 | = Unexpanded[I].first.dyn_cast<const TemplateTypeParmType *>()) |
| 128 | Name = TTP->getName(); |
| 129 | else |
| 130 | Name = Unexpanded[I].first.get<NamedDecl *>()->getIdentifier(); |
| 131 | |
| 132 | if (Name && NamesKnown.insert(Name)) |
| 133 | Names.push_back(Name); |
| 134 | |
| 135 | if (Unexpanded[I].second.isValid()) |
| 136 | Locations.push_back(Unexpanded[I].second); |
| 137 | } |
| 138 | |
| 139 | DiagnosticBuilder DB |
| 140 | = Names.size() == 0? S.Diag(Loc, diag::err_unexpanded_parameter_pack_0) |
| 141 | << (int)UPPC |
| 142 | : Names.size() == 1? S.Diag(Loc, diag::err_unexpanded_parameter_pack_1) |
| 143 | << (int)UPPC << Names[0] |
| 144 | : Names.size() == 2? S.Diag(Loc, diag::err_unexpanded_parameter_pack_2) |
| 145 | << (int)UPPC << Names[0] << Names[1] |
| 146 | : S.Diag(Loc, diag::err_unexpanded_parameter_pack_3_or_more) |
| 147 | << (int)UPPC << Names[0] << Names[1]; |
| 148 | |
| 149 | for (unsigned I = 0, N = Locations.size(); I != N; ++I) |
| 150 | DB << SourceRange(Locations[I]); |
| 151 | } |
| 152 | |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 153 | bool Sema::DiagnoseUnexpandedParameterPack(SourceLocation Loc, |
| 154 | TypeSourceInfo *T, |
| 155 | UnexpandedParameterPackContext UPPC) { |
| 156 | // C++0x [temp.variadic]p5: |
| 157 | // An appearance of a name of a parameter pack that is not expanded is |
| 158 | // ill-formed. |
| 159 | if (!T->getType()->containsUnexpandedParameterPack()) |
| 160 | return false; |
| 161 | |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 162 | llvm::SmallVector<UnexpandedParameterPack, 2> Unexpanded; |
| 163 | CollectUnexpandedParameterPacksVisitor(Unexpanded).TraverseTypeLoc( |
| 164 | T->getTypeLoc()); |
| 165 | assert(!Unexpanded.empty() && "Unable to find unexpanded parameter packs"); |
| 166 | DiagnoseUnexpandedParameterPacks(*this, Loc, UPPC, Unexpanded); |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 167 | return true; |
| 168 | } |
| 169 | |
| 170 | bool Sema::DiagnoseUnexpandedParameterPack(Expr *E, |
Douglas Gregor | 56c0458 | 2010-12-16 00:46:58 +0000 | [diff] [blame] | 171 | UnexpandedParameterPackContext UPPC) { |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 172 | // C++0x [temp.variadic]p5: |
| 173 | // An appearance of a name of a parameter pack that is not expanded is |
| 174 | // ill-formed. |
| 175 | if (!E->containsUnexpandedParameterPack()) |
| 176 | return false; |
| 177 | |
Douglas Gregor | 9ef7589 | 2010-12-15 19:43:21 +0000 | [diff] [blame] | 178 | llvm::SmallVector<UnexpandedParameterPack, 2> Unexpanded; |
| 179 | CollectUnexpandedParameterPacksVisitor(Unexpanded).TraverseStmt(E); |
| 180 | assert(!Unexpanded.empty() && "Unable to find unexpanded parameter packs"); |
| 181 | DiagnoseUnexpandedParameterPacks(*this, E->getLocStart(), UPPC, Unexpanded); |
Douglas Gregor | c463335 | 2010-12-15 17:38:57 +0000 | [diff] [blame] | 182 | return true; |
| 183 | } |
Douglas Gregor | 56c0458 | 2010-12-16 00:46:58 +0000 | [diff] [blame] | 184 | |
| 185 | bool Sema::DiagnoseUnexpandedParameterPack(const CXXScopeSpec &SS, |
| 186 | UnexpandedParameterPackContext UPPC) { |
| 187 | // C++0x [temp.variadic]p5: |
| 188 | // An appearance of a name of a parameter pack that is not expanded is |
| 189 | // ill-formed. |
| 190 | if (!SS.getScopeRep() || |
| 191 | !SS.getScopeRep()->containsUnexpandedParameterPack()) |
| 192 | return false; |
| 193 | |
| 194 | llvm::SmallVector<UnexpandedParameterPack, 2> Unexpanded; |
| 195 | CollectUnexpandedParameterPacksVisitor(Unexpanded) |
| 196 | .TraverseNestedNameSpecifier(SS.getScopeRep()); |
| 197 | assert(!Unexpanded.empty() && "Unable to find unexpanded parameter packs"); |
| 198 | DiagnoseUnexpandedParameterPacks(*this, SS.getRange().getBegin(), |
| 199 | UPPC, Unexpanded); |
| 200 | return true; |
| 201 | } |
| 202 | |
| 203 | bool Sema::DiagnoseUnexpandedParameterPack(const DeclarationNameInfo &NameInfo, |
| 204 | UnexpandedParameterPackContext UPPC) { |
| 205 | // C++0x [temp.variadic]p5: |
| 206 | // An appearance of a name of a parameter pack that is not expanded is |
| 207 | // ill-formed. |
| 208 | switch (NameInfo.getName().getNameKind()) { |
| 209 | case DeclarationName::Identifier: |
| 210 | case DeclarationName::ObjCZeroArgSelector: |
| 211 | case DeclarationName::ObjCOneArgSelector: |
| 212 | case DeclarationName::ObjCMultiArgSelector: |
| 213 | case DeclarationName::CXXOperatorName: |
| 214 | case DeclarationName::CXXLiteralOperatorName: |
| 215 | case DeclarationName::CXXUsingDirective: |
| 216 | return false; |
| 217 | |
| 218 | case DeclarationName::CXXConstructorName: |
| 219 | case DeclarationName::CXXDestructorName: |
| 220 | case DeclarationName::CXXConversionFunctionName: |
Douglas Gregor | 099ffe8 | 2010-12-16 17:19:19 +0000 | [diff] [blame] | 221 | // FIXME: We shouldn't need this null check! |
Douglas Gregor | 0762bfd | 2010-12-16 01:40:04 +0000 | [diff] [blame] | 222 | if (TypeSourceInfo *TSInfo = NameInfo.getNamedTypeInfo()) |
| 223 | return DiagnoseUnexpandedParameterPack(NameInfo.getLoc(), TSInfo, UPPC); |
| 224 | |
| 225 | if (!NameInfo.getName().getCXXNameType()->containsUnexpandedParameterPack()) |
Douglas Gregor | 56c0458 | 2010-12-16 00:46:58 +0000 | [diff] [blame] | 226 | return false; |
Douglas Gregor | 0762bfd | 2010-12-16 01:40:04 +0000 | [diff] [blame] | 227 | |
Douglas Gregor | 56c0458 | 2010-12-16 00:46:58 +0000 | [diff] [blame] | 228 | break; |
| 229 | } |
| 230 | |
| 231 | llvm::SmallVector<UnexpandedParameterPack, 2> Unexpanded; |
| 232 | CollectUnexpandedParameterPacksVisitor(Unexpanded) |
Douglas Gregor | 0762bfd | 2010-12-16 01:40:04 +0000 | [diff] [blame] | 233 | .TraverseType(NameInfo.getName().getCXXNameType()); |
Douglas Gregor | 56c0458 | 2010-12-16 00:46:58 +0000 | [diff] [blame] | 234 | assert(!Unexpanded.empty() && "Unable to find unexpanded parameter packs"); |
| 235 | DiagnoseUnexpandedParameterPacks(*this, NameInfo.getLoc(), UPPC, Unexpanded); |
| 236 | return true; |
| 237 | } |
Douglas Gregor | 6f52675 | 2010-12-16 08:48:57 +0000 | [diff] [blame] | 238 | |
| 239 | bool Sema::DiagnoseUnexpandedParameterPack(SourceLocation Loc, |
| 240 | TemplateName Template, |
| 241 | UnexpandedParameterPackContext UPPC) { |
| 242 | |
| 243 | if (Template.isNull() || !Template.containsUnexpandedParameterPack()) |
| 244 | return false; |
| 245 | |
| 246 | llvm::SmallVector<UnexpandedParameterPack, 2> Unexpanded; |
| 247 | CollectUnexpandedParameterPacksVisitor(Unexpanded) |
| 248 | .TraverseTemplateName(Template); |
| 249 | assert(!Unexpanded.empty() && "Unable to find unexpanded parameter packs"); |
| 250 | DiagnoseUnexpandedParameterPacks(*this, Loc, UPPC, Unexpanded); |
| 251 | return true; |
| 252 | } |
| 253 | |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 254 | void Sema::collectUnexpandedParameterPacks(TemplateArgumentLoc Arg, |
| 255 | llvm::SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) { |
| 256 | CollectUnexpandedParameterPacksVisitor(Unexpanded) |
| 257 | .TraverseTemplateArgumentLoc(Arg); |
| 258 | } |
| 259 | |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 260 | ParsedTemplateArgument |
| 261 | Sema::ActOnPackExpansion(const ParsedTemplateArgument &Arg, |
| 262 | SourceLocation EllipsisLoc) { |
| 263 | if (Arg.isInvalid()) |
| 264 | return Arg; |
| 265 | |
| 266 | switch (Arg.getKind()) { |
| 267 | case ParsedTemplateArgument::Type: { |
| 268 | TypeResult Result = ActOnPackExpansion(Arg.getAsType(), EllipsisLoc); |
| 269 | if (Result.isInvalid()) |
| 270 | return ParsedTemplateArgument(); |
| 271 | |
| 272 | return ParsedTemplateArgument(Arg.getKind(), Result.get().getAsOpaquePtr(), |
| 273 | Arg.getLocation()); |
| 274 | } |
| 275 | |
| 276 | case ParsedTemplateArgument::NonType: |
| 277 | Diag(EllipsisLoc, diag::err_pack_expansion_unsupported) |
| 278 | << 0; |
| 279 | return ParsedTemplateArgument(); |
| 280 | |
| 281 | case ParsedTemplateArgument::Template: |
| 282 | Diag(EllipsisLoc, diag::err_pack_expansion_unsupported) |
| 283 | << 1; |
| 284 | return ParsedTemplateArgument(); |
| 285 | } |
| 286 | llvm_unreachable("Unhandled template argument kind?"); |
| 287 | return ParsedTemplateArgument(); |
| 288 | } |
| 289 | |
| 290 | TypeResult Sema::ActOnPackExpansion(ParsedType Type, |
| 291 | SourceLocation EllipsisLoc) { |
| 292 | TypeSourceInfo *TSInfo; |
| 293 | GetTypeFromParser(Type, &TSInfo); |
| 294 | if (!TSInfo) |
| 295 | return true; |
| 296 | |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 297 | TypeSourceInfo *TSResult = CheckPackExpansion(TSInfo, EllipsisLoc); |
| 298 | if (!TSResult) |
| 299 | return true; |
| 300 | |
| 301 | return CreateParsedType(TSResult->getType(), TSResult); |
| 302 | } |
| 303 | |
| 304 | TypeSourceInfo *Sema::CheckPackExpansion(TypeSourceInfo *Pattern, |
| 305 | SourceLocation EllipsisLoc) { |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 306 | // C++0x [temp.variadic]p5: |
| 307 | // The pattern of a pack expansion shall name one or more |
| 308 | // parameter packs that are not expanded by a nested pack |
| 309 | // expansion. |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 310 | if (!Pattern->getType()->containsUnexpandedParameterPack()) { |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 311 | Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs) |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 312 | << Pattern->getTypeLoc().getSourceRange(); |
| 313 | return 0; |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 314 | } |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 315 | |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 316 | // Create the pack expansion type and source-location information. |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 317 | QualType Result = Context.getPackExpansionType(Pattern->getType()); |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 318 | TypeSourceInfo *TSResult = Context.CreateTypeSourceInfo(Result); |
| 319 | PackExpansionTypeLoc TL = cast<PackExpansionTypeLoc>(TSResult->getTypeLoc()); |
| 320 | TL.setEllipsisLoc(EllipsisLoc); |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 321 | |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 322 | // Copy over the source-location information from the type. |
| 323 | memcpy(TL.getNextTypeLoc().getOpaqueData(), |
Douglas Gregor | 8491ffe | 2010-12-20 22:05:00 +0000 | [diff] [blame^] | 324 | Pattern->getTypeLoc().getOpaqueData(), |
| 325 | Pattern->getTypeLoc().getFullDataSize()); |
| 326 | return TSResult; |
Douglas Gregor | 7536dd5 | 2010-12-20 02:24:11 +0000 | [diff] [blame] | 327 | } |