Add an AdjustedType sugar node for adjusting calling conventions

rnk · rnk · commit 8e77b2bb5a22 · 2013-12-05T01:23:43.000Z
Summary: In general, this type node can be used to represent any type adjustment that occurs implicitly without losing type sugar. The immediate use of this is to adjust the calling conventions of member function pointer types without breaking template instantiation. Fixes PR17996. Reviewers: rsmith Differential Revision: http://llvm-reviews.chandlerc.com/D2332 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196451 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
@@ -82,7 +82,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
   mutable llvm::FoldingSet<ExtQuals> ExtQualNodes;
   mutable llvm::FoldingSet<ComplexType> ComplexTypes;
   mutable llvm::FoldingSet<PointerType> PointerTypes;
-  mutable llvm::FoldingSet<DecayedType> DecayedTypes;
+  mutable llvm::FoldingSet<AdjustedType> AdjustedTypes;
   mutable llvm::FoldingSet<BlockPointerType> BlockPointerTypes;
   mutable llvm::FoldingSet<LValueReferenceType> LValueReferenceTypes;
   mutable llvm::FoldingSet<RValueReferenceType> RValueReferenceTypes;
@@ -915,6 +915,14 @@ class ASTContext : public RefCountedBase<ASTContext> {
     return CanQualType::CreateUnsafe(getPointerType((QualType) T));
   }
 
+  /// \brief Return the uniqued reference to a type adjusted from the original
+  /// type to a new type.
+  QualType getAdjustedType(QualType Orig, QualType New) const;
+  CanQualType getAdjustedType(CanQualType Orig, CanQualType New) const {
+    return CanQualType::CreateUnsafe(
+        getAdjustedType((QualType)Orig, (QualType)New));
+  }
+
   /// \brief Return the uniqued reference to the decayed version of the given
   /// type.  Can only be called on array and function types which decay to
   /// pointer types.
diff --git a/include/clang/AST/RecursiveASTVisitor.h b/include/clang/AST/RecursiveASTVisitor.h
@@ -874,6 +874,10 @@ DEF_TRAVERSE_TYPE(MemberPointerType, {
     TRY_TO(TraverseType(T->getPointeeType()));
   })
 
+DEF_TRAVERSE_TYPE(AdjustedType, {
+    TRY_TO(TraverseType(T->getOriginalType()));
+  })
+
 DEF_TRAVERSE_TYPE(DecayedType, {
     TRY_TO(TraverseType(T->getOriginalType()));
   })
@@ -1084,6 +1088,10 @@ DEF_TRAVERSE_TYPELOC(MemberPointerType, {
     TRY_TO(TraverseTypeLoc(TL.getPointeeLoc()));
   })
 
+DEF_TRAVERSE_TYPELOC(AdjustedType, {
+    TRY_TO(TraverseTypeLoc(TL.getOriginalLoc()));
+  })
+
 DEF_TRAVERSE_TYPELOC(DecayedType, {
     TRY_TO(TraverseTypeLoc(TL.getOriginalLoc()));
   })
diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
@@ -1996,39 +1996,59 @@ class PointerType : public Type, public llvm::FoldingSetNode {
   static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
 };
 
-/// \brief Represents a pointer type decayed from an array or function type.
-class DecayedType : public Type, public llvm::FoldingSetNode {
-  QualType OriginalType;
-  QualType DecayedPointer;
+/// \brief Represents a type which was implicitly adjusted by the semantic
+/// engine for arbitrary reasons.  For example, array and function types can
+/// decay, and function types can have their calling conventions adjusted.
+class AdjustedType : public Type, public llvm::FoldingSetNode {
+  QualType OriginalTy;
+  QualType AdjustedTy;
 
-  DecayedType(QualType OriginalType, QualType DecayedPointer,
-              QualType CanonicalPtr)
-      : Type(Decayed, CanonicalPtr, OriginalType->isDependentType(),
-             OriginalType->isInstantiationDependentType(),
-             OriginalType->isVariablyModifiedType(),
-             OriginalType->containsUnexpandedParameterPack()),
-        OriginalType(OriginalType), DecayedPointer(DecayedPointer) {
-    assert(isa<PointerType>(DecayedPointer));
-  }
+protected:
+  AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
+               QualType CanonicalPtr)
+      : Type(TC, CanonicalPtr, OriginalTy->isDependentType(),
+             OriginalTy->isInstantiationDependentType(),
+             OriginalTy->isVariablyModifiedType(),
+             OriginalTy->containsUnexpandedParameterPack()),
+        OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}
 
   friend class ASTContext;  // ASTContext creates these.
 
 public:
-  QualType getDecayedType() const { return DecayedPointer; }
-  QualType getOriginalType() const { return OriginalType; }
-
-  QualType getPointeeType() const {
-    return cast<PointerType>(DecayedPointer)->getPointeeType();
-  }
+  QualType getOriginalType() const { return OriginalTy; }
+  QualType getAdjustedType() const { return AdjustedTy; }
 
   bool isSugared() const { return true; }
-  QualType desugar() const { return DecayedPointer; }
+  QualType desugar() const { return AdjustedTy; }
 
   void Profile(llvm::FoldingSetNodeID &ID) {
-    Profile(ID, OriginalType);
+    Profile(ID, OriginalTy, AdjustedTy);
   }
-  static void Profile(llvm::FoldingSetNodeID &ID, QualType OriginalType) {
-    ID.AddPointer(OriginalType.getAsOpaquePtr());
+  static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
+    ID.AddPointer(Orig.getAsOpaquePtr());
+    ID.AddPointer(New.getAsOpaquePtr());
+  }
+
+  static bool classof(const Type *T) {
+    return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
+  }
+};
+
+/// \brief Represents a pointer type decayed from an array or function type.
+class DecayedType : public AdjustedType {
+
+  DecayedType(QualType OriginalType, QualType DecayedPtr, QualType CanonicalPtr)
+      : AdjustedType(Decayed, OriginalType, DecayedPtr, CanonicalPtr) {
+    assert(isa<PointerType>(getAdjustedType()));
+  }
+
+  friend class ASTContext;  // ASTContext creates these.
+
+public:
+  QualType getDecayedType() const { return getAdjustedType(); }
+
+  QualType getPointeeType() const {
+    return cast<PointerType>(getDecayedType())->getPointeeType();
   }
 
   static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
diff --git a/include/clang/AST/TypeLoc.h b/include/clang/AST/TypeLoc.h
@@ -978,12 +978,10 @@ inline TypeLoc TypeLoc::IgnoreParens() const {
 }
 
 
-struct DecayedLocInfo { }; // Nothing.
+struct AdjustedLocInfo { }; // Nothing.
 
-/// \brief Wrapper for source info for pointers decayed from arrays and
-/// functions.
-class DecayedTypeLoc : public ConcreteTypeLoc<UnqualTypeLoc, DecayedTypeLoc,
-                                              DecayedType, DecayedLocInfo> {
+class AdjustedTypeLoc : public ConcreteTypeLoc<UnqualTypeLoc, AdjustedTypeLoc,
+                                               AdjustedType, AdjustedLocInfo> {
 public:
   TypeLoc getOriginalLoc() const {
     return getInnerTypeLoc();
@@ -1004,12 +1002,17 @@ class DecayedTypeLoc : public ConcreteTypeLoc<UnqualTypeLoc, DecayedTypeLoc,
   }
 
   unsigned getLocalDataSize() const {
-    // sizeof(DecayedLocInfo) is 1, but we don't need its address to be unique
+    // sizeof(AdjustedLocInfo) is 1, but we don't need its address to be unique
     // anyway.  TypeLocBuilder can't handle data sizes of 1.
     return 0;  // No data.
   }
 };
 
+/// \brief Wrapper for source info for pointers decayed from arrays and
+/// functions.
+class DecayedTypeLoc : public InheritingConcreteTypeLoc<
+                           AdjustedTypeLoc, DecayedTypeLoc, DecayedType> {
+};
 
 struct PointerLikeLocInfo {
   SourceLocation StarLoc;
diff --git a/include/clang/AST/TypeNodes.def b/include/clang/AST/TypeNodes.def
@@ -81,7 +81,8 @@ TYPE(FunctionNoProto, FunctionType)
 DEPENDENT_TYPE(UnresolvedUsing, Type)
 NON_CANONICAL_TYPE(Paren, Type)
 NON_CANONICAL_TYPE(Typedef, Type)
-NON_CANONICAL_TYPE(Decayed, Type)
+NON_CANONICAL_TYPE(Adjusted, Type)
+NON_CANONICAL_TYPE(Decayed, AdjustedType)
 NON_CANONICAL_UNLESS_DEPENDENT_TYPE(TypeOfExpr, Type)
 NON_CANONICAL_UNLESS_DEPENDENT_TYPE(TypeOf, Type)
 NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Decltype, Type)
diff --git a/include/clang/Serialization/ASTBitCodes.h b/include/clang/Serialization/ASTBitCodes.h
@@ -841,7 +841,9 @@ namespace clang {
       /// \brief An AtomicType record.
       TYPE_ATOMIC                = 40,
       /// \brief A DecayedType record.
-      TYPE_DECAYED               = 41
+      TYPE_DECAYED               = 41,
+      /// \brief An AdjustedType record.
+      TYPE_ADJUSTED              = 42
     };
 
     /// \brief The type IDs for special types constructed by semantic
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
@@ -1632,8 +1632,9 @@ ASTContext::getTypeInfoImpl(const Type *T) const {
   }
   case Type::ObjCObject:
     return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
+  case Type::Adjusted:
   case Type::Decayed:
-    return getTypeInfo(cast<DecayedType>(T)->getDecayedType().getTypePtr());
+    return getTypeInfo(cast<AdjustedType>(T)->getAdjustedType().getTypePtr());
   case Type::ObjCInterface: {
     const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
     const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
@@ -2163,14 +2164,29 @@ QualType ASTContext::getPointerType(QualType T) const {
   return QualType(New, 0);
 }
 
-QualType ASTContext::getDecayedType(QualType T) const {
-  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
-
+QualType ASTContext::getAdjustedType(QualType Orig, QualType New) const {
   llvm::FoldingSetNodeID ID;
-  DecayedType::Profile(ID, T);
+  AdjustedType::Profile(ID, Orig, New);
   void *InsertPos = 0;
-  if (DecayedType *DT = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos))
-    return QualType(DT, 0);
+  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
+  if (AT)
+    return QualType(AT, 0);
+
+  QualType Canonical = getCanonicalType(New);
+
+  // Get the new insert position for the node we care about.
+  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
+  assert(AT == 0 && "Shouldn't be in the map!");
+
+  AT = new (*this, TypeAlignment)
+      AdjustedType(Type::Adjusted, Orig, New, Canonical);
+  Types.push_back(AT);
+  AdjustedTypes.InsertNode(AT, InsertPos);
+  return QualType(AT, 0);
+}
+
+QualType ASTContext::getDecayedType(QualType T) const {
+  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
 
   QualType Decayed;
 
@@ -2189,17 +2205,23 @@ QualType ASTContext::getDecayedType(QualType T) const {
   if (T->isFunctionType())
     Decayed = getPointerType(T);
 
+  llvm::FoldingSetNodeID ID;
+  AdjustedType::Profile(ID, T, Decayed);
+  void *InsertPos = 0;
+  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
+  if (AT)
+    return QualType(AT, 0);
+
   QualType Canonical = getCanonicalType(Decayed);
 
   // Get the new insert position for the node we care about.
-  DecayedType *NewIP = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos);
-  assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
+  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
+  assert(AT == 0 && "Shouldn't be in the map!");
 
-  DecayedType *New =
-      new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
-  Types.push_back(New);
-  DecayedTypes.InsertNode(New, InsertPos);
-  return QualType(New, 0);
+  AT = new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
+  Types.push_back(AT);
+  AdjustedTypes.InsertNode(AT, InsertPos);
+  return QualType(AT, 0);
 }
 
 /// getBlockPointerType - Return the uniqued reference to the type for
diff --git a/lib/AST/ASTDiagnostic.cpp b/lib/AST/ASTDiagnostic.cpp
@@ -51,6 +51,11 @@ static QualType Desugar(ASTContext &Context, QualType QT, bool &ShouldAKA) {
       QT = AT->desugar();
       continue;
     }
+    // ...or an adjusted type...
+    if (const AdjustedType *AT = dyn_cast<AdjustedType>(Ty)) {
+      QT = AT->desugar();
+      continue;
+    }
     // ... or an auto type.
     if (const AutoType *AT = dyn_cast<AutoType>(Ty)) {
       if (!AT->isSugared())
diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
@@ -407,10 +407,11 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
       return false;
     break;
   
+  case Type::Adjusted:
   case Type::Decayed:
     if (!IsStructurallyEquivalent(Context,
-                                  cast<DecayedType>(T1)->getPointeeType(),
-                                  cast<DecayedType>(T2)->getPointeeType()))
+                                  cast<AdjustedType>(T1)->getOriginalType(),
+                                  cast<AdjustedType>(T2)->getOriginalType()))
       return false;
     break;
 
diff --git a/lib/AST/Comment.cpp b/lib/AST/Comment.cpp
@@ -251,6 +251,11 @@ void DeclInfo::fill() {
         TL = PointerTL.getPointeeLoc().getUnqualifiedLoc();
         continue;
       }
+      // Look through adjusted types.
+      if (AdjustedTypeLoc ATL = TL.getAs<AdjustedTypeLoc>()) {
+        TL = ATL.getOriginalLoc();
+        continue;
+      }
       if (BlockPointerTypeLoc BlockPointerTL =
               TL.getAs<BlockPointerTypeLoc>()) {
         TL = BlockPointerTL.getPointeeLoc().getUnqualifiedLoc();
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
@@ -2508,11 +2508,8 @@ unsigned FunctionDecl::getBuiltinID() const {
 /// based on its FunctionType.  This is the length of the ParamInfo array
 /// after it has been created.
 unsigned FunctionDecl::getNumParams() const {
-  const FunctionType *FT = getType()->castAs<FunctionType>();
-  if (isa<FunctionNoProtoType>(FT))
-    return 0;
-  return cast<FunctionProtoType>(FT)->getNumArgs();
-
+  const FunctionProtoType *FPT = getType()->getAs<FunctionProtoType>();
+  return FPT ? FPT->getNumArgs() : 0;
 }
 
 void FunctionDecl::setParams(ASTContext &C,
diff --git a/lib/AST/DeclPrinter.cpp b/lib/AST/DeclPrinter.cpp
@@ -423,8 +423,7 @@ void DeclPrinter::VisitFunctionDecl(FunctionDecl *D) {
     Ty = PT->getInnerType();
   }
 
-  if (isa<FunctionType>(Ty)) {
-    const FunctionType *AFT = Ty->getAs<FunctionType>();
+  if (const FunctionType *AFT = Ty->getAs<FunctionType>()) {
     const FunctionProtoType *FT = 0;
     if (D->hasWrittenPrototype())
       FT = dyn_cast<FunctionProtoType>(AFT);
diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
@@ -833,6 +833,7 @@ void CXXNameMangler::mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
     switch (type->getTypeClass()) {
     case Type::Builtin:
     case Type::Complex:
+    case Type::Adjusted:
     case Type::Decayed:
     case Type::Pointer:
     case Type::BlockPointer:
diff --git a/lib/AST/Type.cpp b/lib/AST/Type.cpp
@@ -593,6 +593,9 @@ namespace {
     AutoType *VisitAttributedType(const AttributedType *T) {
       return Visit(T->getModifiedType());
     }
+    AutoType *VisitAdjustedType(const AdjustedType *T) {
+      return Visit(T->getOriginalType());
+    }
   };
 }
 
diff --git a/lib/AST/TypePrinter.cpp b/lib/AST/TypePrinter.cpp
@@ -204,6 +204,7 @@ bool TypePrinter::canPrefixQualifiers(const Type *T,
       NeedARCStrongQualifier = true;
       // Fall through
       
+    case Type::Adjusted:
     case Type::Decayed:
     case Type::Pointer:
     case Type::BlockPointer:
@@ -471,12 +472,21 @@ void TypePrinter::printVariableArrayAfter(const VariableArrayType *T,
   printAfter(T->getElementType(), OS);
 }
 
+void TypePrinter::printAdjustedBefore(const AdjustedType *T, raw_ostream &OS) {
+  // Print the adjusted representation, otherwise the adjustment will be
+  // invisible.
+  printBefore(T->getAdjustedType(), OS);
+}
+void TypePrinter::printAdjustedAfter(const AdjustedType *T, raw_ostream &OS) {
+  printAfter(T->getAdjustedType(), OS);
+}
+
 void TypePrinter::printDecayedBefore(const DecayedType *T, raw_ostream &OS) {
   // Print as though it's a pointer.
-  printBefore(T->getDecayedType(), OS);
+  printAdjustedBefore(T, OS);
 }
 void TypePrinter::printDecayedAfter(const DecayedType *T, raw_ostream &OS) {
-  printAfter(T->getDecayedType(), OS);
+  printAdjustedAfter(T, OS);
 }
 
 void TypePrinter::printDependentSizedArrayBefore(
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
@@ -2123,10 +2123,11 @@ llvm::DIType CGDebugInfo::CreateTypeNode(QualType Ty, llvm::DIFile Unit) {
     return CreateType(cast<ComplexType>(Ty));
   case Type::Pointer:
     return CreateType(cast<PointerType>(Ty), Unit);
+  case Type::Adjusted:
   case Type::Decayed:
-    // Decayed types are just pointers in LLVM and DWARF.
+    // Decayed and adjusted types use the adjusted type in LLVM and DWARF.
     return CreateType(
-        cast<PointerType>(cast<DecayedType>(Ty)->getDecayedType()), Unit);
+        cast<PointerType>(cast<AdjustedType>(Ty)->getAdjustedType()), Unit);
   case Type::BlockPointer:
     return CreateType(cast<BlockPointerType>(Ty), Unit);
   case Type::Typedef:
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
@@ -1308,6 +1308,10 @@ void CodeGenFunction::EmitVariablyModifiedType(QualType type) {
     case Type::ObjCObjectPointer:
       llvm_unreachable("type class is never variably-modified!");
 
+    case Type::Adjusted:
+      type = cast<AdjustedType>(ty)->getAdjustedType();
+      break;
+
     case Type::Decayed:
       type = cast<DecayedType>(ty)->getPointeeType();
       break;
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
diff --git a/test/SemaCXX/calling-conv-compat.cpp b/test/SemaCXX/calling-conv-compat.cpp
diff --git a/test/SemaCXX/decl-microsoft-call-conv.cpp b/test/SemaCXX/decl-microsoft-call-conv.cpp
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
diff --git a/tools/libclang/RecursiveASTVisitor.h b/tools/libclang/RecursiveASTVisitor.h
