Vendor import of clang trunk r240225:vendor/clang/clang-trunk-r240225

https://llvm.org/svn/llvm-project/cfe/trunk@240225

13 files changed, 445 insertions, 128 deletions

diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 049221ad9144..da288c4fe5ed 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -1854,6 +1854,36 @@ public:
            getCanonicalType(T2).getTypePtr();
   }
 
+  bool hasSameNullabilityTypeQualifier(QualType SubT, QualType SuperT,
+                                       bool IsParam) const {
+    auto SubTnullability = SubT->getNullability(*this);
+    auto SuperTnullability = SuperT->getNullability(*this);
+    if (SubTnullability.hasValue() == SuperTnullability.hasValue()) {
+      // Neither has nullability; return true
+      if (!SubTnullability)
+        return true;
+      // Both have nullability qualifier.
+      if (*SubTnullability == *SuperTnullability ||
+          *SubTnullability == NullabilityKind::Unspecified ||
+          *SuperTnullability == NullabilityKind::Unspecified)
+        return true;
+      
+      if (IsParam) {
+        // Ok for the superclass method parameter to be "nonnull" and the subclass
+        // method parameter to be "nullable"
+        return (*SuperTnullability == NullabilityKind::NonNull &&
+                *SubTnullability == NullabilityKind::Nullable);
+      }
+      else {
+        // For the return type, it's okay for the superclass method to specify
+        // "nullable" and the subclass method specify "nonnull"
+        return (*SuperTnullability == NullabilityKind::Nullable &&
+                *SubTnullability == NullabilityKind::NonNull);
+      }
+    }
+    return true;
+  }
+
   bool ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
                            const ObjCMethodDecl *MethodImp);
   
diff --git a/include/clang/AST/CommentParser.h b/include/clang/AST/CommentParser.h
index 42bf4c989a23..fa8862899c14 100644
--- a/include/clang/AST/CommentParser.h
+++ b/include/clang/AST/CommentParser.h
@@ -75,11 +75,7 @@ class Parser {
       return;
 
     MoreLATokens.push_back(Tok);
-    for (const Token *I = &Toks.back(),
-         *B = &Toks.front();
-         I != B; --I) {
-      MoreLATokens.push_back(*I);
-    }
+    MoreLATokens.append(Toks.rbegin(), std::prev(Toks.rend()));
 
     Tok = Toks[0];
   }
diff --git a/include/clang/AST/DataRecursiveASTVisitor.h b/include/clang/AST/DataRecursiveASTVisitor.h
index 971841e8fb5d..ef8817659338 100644
--- a/include/clang/AST/DataRecursiveASTVisitor.h
+++ b/include/clang/AST/DataRecursiveASTVisitor.h
@@ -531,10 +531,7 @@ bool RecursiveASTVisitor<Derived>::TraverseStmt(Stmt *S) {
       }
     }
 
-    for (SmallVectorImpl<Stmt *>::reverse_iterator RI = StmtsToEnqueue.rbegin(),
-                                                   RE = StmtsToEnqueue.rend();
-         RI != RE; ++RI)
-      Queue.push_back(*RI);
+    Queue.append(StmtsToEnqueue.rbegin(), StmtsToEnqueue.rend());
   }
 
   return true;
@@ -2204,9 +2201,11 @@ DEF_TRAVERSE_STMT(CXXThisExpr, {})
 DEF_TRAVERSE_STMT(CXXThrowExpr, {})
 DEF_TRAVERSE_STMT(UserDefinedLiteral, {})
 DEF_TRAVERSE_STMT(DesignatedInitExpr, {})
+DEF_TRAVERSE_STMT(DesignatedInitUpdateExpr, {})
 DEF_TRAVERSE_STMT(ExtVectorElementExpr, {})
 DEF_TRAVERSE_STMT(GNUNullExpr, {})
 DEF_TRAVERSE_STMT(ImplicitValueInitExpr, {})
+DEF_TRAVERSE_STMT(NoInitExpr, {})
 DEF_TRAVERSE_STMT(ObjCBoolLiteralExpr, {})
 DEF_TRAVERSE_STMT(ObjCEncodeExpr, {
   if (TypeSourceInfo *TInfo = S->getEncodedTypeSourceInfo())
@@ -2356,6 +2355,9 @@ DEF_TRAVERSE_STMT(OMPBarrierDirective,
 DEF_TRAVERSE_STMT(OMPTaskwaitDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 
+DEF_TRAVERSE_STMT(OMPTaskgroupDirective,
+                  { TRY_TO(TraverseOMPExecutableDirective(S)); })
+
 DEF_TRAVERSE_STMT(OMPFlushDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 
diff --git a/include/clang/AST/DeclBase.h b/include/clang/AST/DeclBase.h
index f176e5479e1e..6b6ac3f7d5a5 100644
--- a/include/clang/AST/DeclBase.h
+++ b/include/clang/AST/DeclBase.h
@@ -178,7 +178,12 @@ public:
     OBJC_TQ_Out = 0x4,
     OBJC_TQ_Bycopy = 0x8,
     OBJC_TQ_Byref = 0x10,
-    OBJC_TQ_Oneway = 0x20
+    OBJC_TQ_Oneway = 0x20,
+
+    /// The nullability qualifier is set when the nullability of the
+    /// result or parameter was expressed via a context-sensitive
+    /// keyword.
+    OBJC_TQ_CSNullability = 0x40
   };
 
 protected:
diff --git a/include/clang/AST/DeclCXX.h b/include/clang/AST/DeclCXX.h
index 537ad4640c24..08451c051b57 100644
--- a/include/clang/AST/DeclCXX.h
+++ b/include/clang/AST/DeclCXX.h
@@ -1440,7 +1440,7 @@ public:
   ///
   /// \returns true if this class is derived from \p Base, false otherwise.
   ///
-  /// \todo add a separate paramaeter to configure IsDerivedFrom, rather than
+  /// \todo add a separate parameter to configure IsDerivedFrom, rather than
   /// tangling input and output in \p Paths
   bool isDerivedFrom(const CXXRecordDecl *Base, CXXBasePaths &Paths) const;
 
diff --git a/include/clang/AST/DeclObjC.h b/include/clang/AST/DeclObjC.h
index 4a5b4f3d0756..c3fb57770245 100644
--- a/include/clang/AST/DeclObjC.h
+++ b/include/clang/AST/DeclObjC.h
@@ -141,7 +141,7 @@ private:
 
   // NOTE: VC++ treats enums as signed, avoid using the ObjCDeclQualifier enum
   /// in, inout, etc.
-  unsigned objcDeclQualifier : 6;
+  unsigned objcDeclQualifier : 7;
 
   /// \brief Indicates whether this method has a related result type.
   unsigned RelatedResultType : 1;
@@ -2203,13 +2203,17 @@ public:
     OBJC_PR_atomic    = 0x100,
     OBJC_PR_weak      = 0x200,
     OBJC_PR_strong    = 0x400,
-    OBJC_PR_unsafe_unretained = 0x800
+    OBJC_PR_unsafe_unretained = 0x800,
+    /// Indicates that the nullability of the type was spelled with a
+    /// property attribute rather than a type qualifier.
+    OBJC_PR_nullability = 0x1000,
+    OBJC_PR_null_resettable = 0x2000
     // Adding a property should change NumPropertyAttrsBits
   };
 
   enum {
     /// \brief Number of bits fitting all the property attributes.
-    NumPropertyAttrsBits = 12
+    NumPropertyAttrsBits = 14
   };
 
   enum SetterKind { Assign, Retain, Copy, Weak };
@@ -2217,7 +2221,8 @@ public:
 private:
   SourceLocation AtLoc;   // location of \@property
   SourceLocation LParenLoc; // location of '(' starting attribute list or null.
-  TypeSourceInfo *DeclType;
+  QualType DeclType;
+  TypeSourceInfo *DeclTypeSourceInfo;
   unsigned PropertyAttributes : NumPropertyAttrsBits;
   unsigned PropertyAttributesAsWritten : NumPropertyAttrsBits;
   // \@required/\@optional
@@ -2232,12 +2237,13 @@ private:
 
   ObjCPropertyDecl(DeclContext *DC, SourceLocation L, IdentifierInfo *Id,
                    SourceLocation AtLocation,  SourceLocation LParenLocation,
-                   TypeSourceInfo *T)
+                   QualType T, TypeSourceInfo *TSI,
+                   PropertyControl propControl)
     : NamedDecl(ObjCProperty, DC, L, Id), AtLoc(AtLocation), 
-      LParenLoc(LParenLocation), DeclType(T),
+      LParenLoc(LParenLocation), DeclType(T), DeclTypeSourceInfo(TSI),
       PropertyAttributes(OBJC_PR_noattr),
       PropertyAttributesAsWritten(OBJC_PR_noattr),
-      PropertyImplementation(None),
+      PropertyImplementation(propControl),
       GetterName(Selector()),
       SetterName(Selector()),
       GetterMethodDecl(nullptr), SetterMethodDecl(nullptr),
@@ -2248,7 +2254,8 @@ public:
                                   SourceLocation L,
                                   IdentifierInfo *Id, SourceLocation AtLocation,
                                   SourceLocation LParenLocation,
-                                  TypeSourceInfo *T,
+                                  QualType T,
+                                  TypeSourceInfo *TSI,
                                   PropertyControl propControl = None);
   
   static ObjCPropertyDecl *CreateDeserialized(ASTContext &C, unsigned ID);
@@ -2259,9 +2266,14 @@ public:
   SourceLocation getLParenLoc() const { return LParenLoc; }
   void setLParenLoc(SourceLocation L) { LParenLoc = L; }
 
-  TypeSourceInfo *getTypeSourceInfo() const { return DeclType; }
-  QualType getType() const { return DeclType->getType(); }
-  void setType(TypeSourceInfo *T) { DeclType = T; }
+  TypeSourceInfo *getTypeSourceInfo() const { return DeclTypeSourceInfo; }
+
+  QualType getType() const { return DeclType; }
+
+  void setType(QualType T, TypeSourceInfo *TSI) { 
+    DeclType = T;
+    DeclTypeSourceInfo = TSI; 
+  }
 
   PropertyAttributeKind getPropertyAttributes() const {
     return PropertyAttributeKind(PropertyAttributes);
diff --git a/include/clang/AST/DeclTemplate.h b/include/clang/AST/DeclTemplate.h
index 90cfb2049173..0fc9b4947d49 100644
--- a/include/clang/AST/DeclTemplate.h
+++ b/include/clang/AST/DeclTemplate.h
@@ -217,6 +217,88 @@ public:
   }
 };
 
+void *allocateDefaultArgStorageChain(const ASTContext &C);
+
+/// Storage for a default argument. This is conceptually either empty, or an
+/// argument value, or a pointer to a previous declaration that had a default
+/// argument.
+///
+/// However, this is complicated by modules: while we require all the default
+/// arguments for a template to be equivalent, there may be more than one, and
+/// we need to track all the originating parameters to determine if the default
+/// argument is visible.
+template<typename ParmDecl, typename ArgType>
+class DefaultArgStorage {
+  /// Storage for both the value *and* another parameter from which we inherit
+  /// the default argument. This is used when multiple default arguments for a
+  /// parameter are merged together from different modules.
+  struct Chain {
+    ParmDecl *PrevDeclWithDefaultArg;
+    ArgType Value;
+  };
+  static_assert(sizeof(Chain) == sizeof(void *) * 2,
+                "non-pointer argument type?");
+
+  llvm::PointerUnion3<ArgType, ParmDecl*, Chain*> ValueOrInherited;
+
+  static ParmDecl *getParmOwningDefaultArg(ParmDecl *Parm) {
+    const DefaultArgStorage &Storage = Parm->getDefaultArgStorage();
+    if (auto *Prev = Storage.ValueOrInherited.template dyn_cast<ParmDecl*>())
+      Parm = Prev;
+    assert(!Parm->getDefaultArgStorage()
+                .ValueOrInherited.template is<ParmDecl *>() &&
+           "should only be one level of indirection");
+    return Parm;
+  }
+
+public:
+  DefaultArgStorage() : ValueOrInherited(ArgType()) {}
+
+  /// Determine whether there is a default argument for this parameter.
+  bool isSet() const { return !ValueOrInherited.isNull(); }
+  /// Determine whether the default argument for this parameter was inherited
+  /// from a previous declaration of the same entity.
+  bool isInherited() const { return ValueOrInherited.template is<ParmDecl*>(); }
+  /// Get the default argument's value. This does not consider whether the
+  /// default argument is visible.
+  ArgType get() const {
+    const DefaultArgStorage *Storage = this;
+    if (auto *Prev = ValueOrInherited.template dyn_cast<ParmDecl*>())
+      Storage = &Prev->getDefaultArgStorage();
+    if (auto *C = Storage->ValueOrInherited.template dyn_cast<Chain*>())
+      return C->Value;
+    return Storage->ValueOrInherited.template get<ArgType>();
+  }
+  /// Get the parameter from which we inherit the default argument, if any.
+  /// This is the parameter on which the default argument was actually written.
+  const ParmDecl *getInheritedFrom() const {
+    if (auto *D = ValueOrInherited.template dyn_cast<ParmDecl*>())
+      return D;
+    if (auto *C = ValueOrInherited.template dyn_cast<Chain*>())
+      return C->PrevDeclWithDefaultArg;
+    return nullptr;
+  }
+  /// Set the default argument.
+  void set(ArgType Arg) {
+    assert(!isSet() && "default argument already set");
+    ValueOrInherited = Arg;
+  }
+  /// Set that the default argument was inherited from another parameter.
+  void setInherited(const ASTContext &C, ParmDecl *InheritedFrom) {
+    assert(!isInherited() && "default argument already inherited");
+    InheritedFrom = getParmOwningDefaultArg(InheritedFrom);
+    if (!isSet())
+      ValueOrInherited = InheritedFrom;
+    else
+      ValueOrInherited = new (allocateDefaultArgStorageChain(C))
+          Chain{InheritedFrom, ValueOrInherited.template get<ArgType>()};
+  }
+  /// Remove the default argument, even if it was inherited.
+  void clear() {
+    ValueOrInherited = ArgType();
+  }
+};
+
 //===----------------------------------------------------------------------===//
 // Kinds of Templates
 //===----------------------------------------------------------------------===//
@@ -942,18 +1024,16 @@ class TemplateTypeParmDecl : public TypeDecl {
   /// If false, it was declared with the 'class' keyword.
   bool Typename : 1;
 
-  /// \brief Whether this template type parameter inherited its
-  /// default argument.
-  bool InheritedDefault : 1;
-
   /// \brief The default template argument, if any.
-  TypeSourceInfo *DefaultArgument;
+  typedef DefaultArgStorage<TemplateTypeParmDecl, TypeSourceInfo *>
+      DefArgStorage;
+  DefArgStorage DefaultArgument;
 
   TemplateTypeParmDecl(DeclContext *DC, SourceLocation KeyLoc,
                        SourceLocation IdLoc, IdentifierInfo *Id,
                        bool Typename)
     : TypeDecl(TemplateTypeParm, DC, IdLoc, Id, KeyLoc), Typename(Typename),
-      InheritedDefault(false), DefaultArgument() { }
+      DefaultArgument() { }
 
   /// Sema creates these on the stack during auto type deduction.
   friend class Sema;
@@ -974,35 +1054,45 @@ public:
   /// If not, it was declared with the 'class' keyword.
   bool wasDeclaredWithTypename() const { return Typename; }
 
+  const DefArgStorage &getDefaultArgStorage() const { return DefaultArgument; }
+
   /// \brief Determine whether this template parameter has a default
   /// argument.
-  bool hasDefaultArgument() const { return DefaultArgument != nullptr; }
+  bool hasDefaultArgument() const { return DefaultArgument.isSet(); }
 
   /// \brief Retrieve the default argument, if any.
-  QualType getDefaultArgument() const { return DefaultArgument->getType(); }
+  QualType getDefaultArgument() const {
+    return DefaultArgument.get()->getType();
+  }
 
   /// \brief Retrieves the default argument's source information, if any.
-  TypeSourceInfo *getDefaultArgumentInfo() const { return DefaultArgument; }
+  TypeSourceInfo *getDefaultArgumentInfo() const {
+    return DefaultArgument.get();
+  }
 
   /// \brief Retrieves the location of the default argument declaration.
   SourceLocation getDefaultArgumentLoc() const;
 
   /// \brief Determines whether the default argument was inherited
   /// from a previous declaration of this template.
-  bool defaultArgumentWasInherited() const { return InheritedDefault; }
+  bool defaultArgumentWasInherited() const {
+    return DefaultArgument.isInherited();
+  }
 
-  /// \brief Set the default argument for this template parameter, and
-  /// whether that default argument was inherited from another
-  /// declaration.
-  void setDefaultArgument(TypeSourceInfo *DefArg, bool Inherited) {
-    DefaultArgument = DefArg;
-    InheritedDefault = Inherited;
+  /// \brief Set the default argument for this template parameter.
+  void setDefaultArgument(TypeSourceInfo *DefArg) {
+    DefaultArgument.set(DefArg);
+  }
+  /// \brief Set that this default argument was inherited from another
+  /// parameter.
+  void setInheritedDefaultArgument(const ASTContext &C,
+                                   TemplateTypeParmDecl *Prev) {
+    DefaultArgument.setInherited(C, Prev);
   }
 
   /// \brief Removes the default argument of this template parameter.
   void removeDefaultArgument() {
-    DefaultArgument = nullptr;
-    InheritedDefault = false;
+    DefaultArgument.clear();
   }
 
   /// \brief Set whether this template type parameter was declared with
@@ -1034,7 +1124,8 @@ class NonTypeTemplateParmDecl
   : public DeclaratorDecl, protected TemplateParmPosition {
   /// \brief The default template argument, if any, and whether or not
   /// it was inherited.
-  llvm::PointerIntPair<Expr*, 1, bool> DefaultArgumentAndInherited;
+  typedef DefaultArgStorage<NonTypeTemplateParmDecl, Expr*> DefArgStorage;
+  DefArgStorage DefaultArgument;
 
   // FIXME: Collapse this into TemplateParamPosition; or, just move depth/index
   // down here to save memory.
@@ -1055,9 +1146,8 @@ class NonTypeTemplateParmDecl
                           IdentifierInfo *Id, QualType T,
                           bool ParameterPack, TypeSourceInfo *TInfo)
     : DeclaratorDecl(NonTypeTemplateParm, DC, IdLoc, Id, T, TInfo, StartLoc),
-      TemplateParmPosition(D, P), DefaultArgumentAndInherited(nullptr, false),
-      ParameterPack(ParameterPack), ExpandedParameterPack(false),
-      NumExpandedTypes(0)
+      TemplateParmPosition(D, P), ParameterPack(ParameterPack),
+      ExpandedParameterPack(false), NumExpandedTypes(0)
   { }
 
   NonTypeTemplateParmDecl(DeclContext *DC, SourceLocation StartLoc,
@@ -1097,16 +1187,14 @@ public:
 
   SourceRange getSourceRange() const override LLVM_READONLY;
 
+  const DefArgStorage &getDefaultArgStorage() const { return DefaultArgument; }
+
   /// \brief Determine whether this template parameter has a default
   /// argument.
-  bool hasDefaultArgument() const {
-    return DefaultArgumentAndInherited.getPointer() != nullptr;
-  }
+  bool hasDefaultArgument() const { return DefaultArgument.isSet(); }
 
   /// \brief Retrieve the default argument, if any.
-  Expr *getDefaultArgument() const {
-    return DefaultArgumentAndInherited.getPointer();
-  }
+  Expr *getDefaultArgument() const { return DefaultArgument.get(); }
 
   /// \brief Retrieve the location of the default argument, if any.
   SourceLocation getDefaultArgumentLoc() const;
@@ -1114,22 +1202,20 @@ public:
   /// \brief Determines whether the default argument was inherited
   /// from a previous declaration of this template.
   bool defaultArgumentWasInherited() const {
-    return DefaultArgumentAndInherited.getInt();
+    return DefaultArgument.isInherited();
   }
 
   /// \brief Set the default argument for this template parameter, and
   /// whether that default argument was inherited from another
   /// declaration.
-  void setDefaultArgument(Expr *DefArg, bool Inherited) {
-    DefaultArgumentAndInherited.setPointer(DefArg);
-    DefaultArgumentAndInherited.setInt(Inherited);
+  void setDefaultArgument(Expr *DefArg) { DefaultArgument.set(DefArg); }
+  void setInheritedDefaultArgument(const ASTContext &C,
+                                   NonTypeTemplateParmDecl *Parm) {
+    DefaultArgument.setInherited(C, Parm);
   }
 
   /// \brief Removes the default argument of this template parameter.
-  void removeDefaultArgument() {
-    DefaultArgumentAndInherited.setPointer(nullptr);
-    DefaultArgumentAndInherited.setInt(false);
-  }
+  void removeDefaultArgument() { DefaultArgument.clear(); }
 
   /// \brief Whether this parameter is a non-type template parameter pack.
   ///
@@ -1217,10 +1303,10 @@ class TemplateTemplateParmDecl : public TemplateDecl,
 {
   void anchor() override;
 
-  /// DefaultArgument - The default template argument, if any.
-  TemplateArgumentLoc DefaultArgument;
-  /// Whether or not the default argument was inherited.
-  bool DefaultArgumentWasInherited;
+  /// \brief The default template argument, if any.
+  typedef DefaultArgStorage<TemplateTemplateParmDecl, TemplateArgumentLoc *>
+      DefArgStorage;
+  DefArgStorage DefaultArgument;
 
   /// \brief Whether this parameter is a parameter pack.
   bool ParameterPack;
@@ -1237,8 +1323,7 @@ class TemplateTemplateParmDecl : public TemplateDecl,
                            unsigned D, unsigned P, bool ParameterPack,
                            IdentifierInfo *Id, TemplateParameterList *Params)
     : TemplateDecl(TemplateTemplateParm, DC, L, Id, Params),
-      TemplateParmPosition(D, P), DefaultArgument(),
-      DefaultArgumentWasInherited(false), ParameterPack(ParameterPack),
+      TemplateParmPosition(D, P), ParameterPack(ParameterPack),
       ExpandedParameterPack(false), NumExpandedParams(0)
     { }
 
@@ -1322,15 +1407,16 @@ public:
     return reinterpret_cast<TemplateParameterList *const *>(this + 1)[I];
   }
 
+  const DefArgStorage &getDefaultArgStorage() const { return DefaultArgument; }
+
   /// \brief Determine whether this template parameter has a default
   /// argument.
-  bool hasDefaultArgument() const {
-    return !DefaultArgument.getArgument().isNull();
-  }
+  bool hasDefaultArgument() const { return DefaultArgument.isSet(); }
 
   /// \brief Retrieve the default argument, if any.
   const TemplateArgumentLoc &getDefaultArgument() const {
-    return DefaultArgument;
+    static const TemplateArgumentLoc None;
+    return DefaultArgument.isSet() ? *DefaultArgument.get() : None;
   }
 
   /// \brief Retrieve the location of the default argument, if any.
@@ -1339,22 +1425,21 @@ public:
   /// \brief Determines whether the default argument was inherited
   /// from a previous declaration of this template.
   bool defaultArgumentWasInherited() const {
-    return DefaultArgumentWasInherited;
+    return DefaultArgument.isInherited();
   }
 
   /// \brief Set the default argument for this template parameter, and
   /// whether that default argument was inherited from another
   /// declaration.
-  void setDefaultArgument(const TemplateArgumentLoc &DefArg, bool Inherited) {
-    DefaultArgument = DefArg;
-    DefaultArgumentWasInherited = Inherited;
+  void setDefaultArgument(const ASTContext &C,
+                          const TemplateArgumentLoc &DefArg);
+  void setInheritedDefaultArgument(const ASTContext &C,
+                                   TemplateTemplateParmDecl *Prev) {
+    DefaultArgument.setInherited(C, Prev);
   }
 
   /// \brief Removes the default argument of this template parameter.
-  void removeDefaultArgument() {
-    DefaultArgument = TemplateArgumentLoc();
-    DefaultArgumentWasInherited = false;
-  }
+  void removeDefaultArgument() { DefaultArgument.clear(); }
 
   SourceRange getSourceRange() const override LLVM_READONLY {
     SourceLocation End = getLocation();
diff --git a/include/clang/AST/EvaluatedExprVisitor.h b/include/clang/AST/EvaluatedExprVisitor.h
index 59de104b83f9..5cae5d9eca3f 100644
--- a/include/clang/AST/EvaluatedExprVisitor.h
+++ b/include/clang/AST/EvaluatedExprVisitor.h
@@ -26,29 +26,32 @@ class ASTContext;
   
 /// \brief Given a potentially-evaluated expression, this visitor visits all
 /// of its potentially-evaluated subexpressions, recursively.
-template<typename ImplClass>
-class EvaluatedExprVisitor : public StmtVisitor<ImplClass> {
-  ASTContext &Context;
-  
+template<template <typename> class Ptr, typename ImplClass>
+class EvaluatedExprVisitorBase : public StmtVisitorBase<Ptr, ImplClass, void> {
+protected:
+  const ASTContext &Context;
+
 public:
-  explicit EvaluatedExprVisitor(ASTContext &Context) : Context(Context) { }
-  
+#define PTR(CLASS) typename Ptr<CLASS>::type
+
+  explicit EvaluatedExprVisitorBase(const ASTContext &Context) : Context(Context) { }
+
   // Expressions that have no potentially-evaluated subexpressions (but may have
   // other sub-expressions).
-  void VisitDeclRefExpr(DeclRefExpr *E) { }
-  void VisitOffsetOfExpr(OffsetOfExpr *E) { }
-  void VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E) { }
-  void VisitExpressionTraitExpr(ExpressionTraitExpr *E) { }
-  void VisitBlockExpr(BlockExpr *E) { }
-  void VisitCXXUuidofExpr(CXXUuidofExpr *E) { }  
-  void VisitCXXNoexceptExpr(CXXNoexceptExpr *E) { }
-  
-  void VisitMemberExpr(MemberExpr *E) {
+  void VisitDeclRefExpr(PTR(DeclRefExpr) E) { }
+  void VisitOffsetOfExpr(PTR(OffsetOfExpr) E) { }
+  void VisitUnaryExprOrTypeTraitExpr(PTR(UnaryExprOrTypeTraitExpr) E) { }
+  void VisitExpressionTraitExpr(PTR(ExpressionTraitExpr) E) { }
+  void VisitBlockExpr(PTR(BlockExpr) E) { }
+  void VisitCXXUuidofExpr(PTR(CXXUuidofExpr) E) { }
+  void VisitCXXNoexceptExpr(PTR(CXXNoexceptExpr) E) { }
+
+  void VisitMemberExpr(PTR(MemberExpr) E) {
     // Only the base matters.
     return this->Visit(E->getBase());
   }
-  
-  void VisitChooseExpr(ChooseExpr *E) {
+
+  void VisitChooseExpr(PTR(ChooseExpr) E) {
     // Don't visit either child expression if the condition is dependent.
     if (E->getCond()->isValueDependent())
       return;
@@ -56,7 +59,7 @@ public:
     return this->Visit(E->getChosenSubExpr());
   }
 
-  void VisitGenericSelectionExpr(GenericSelectionExpr *E) {
+  void VisitGenericSelectionExpr(PTR(GenericSelectionExpr) E) {
     // The controlling expression of a generic selection is not evaluated.
 
     // Don't visit either child expression if the condition is type-dependent.
@@ -67,23 +70,23 @@ public:
     return this->Visit(E->getResultExpr());
   }
 
-  void VisitDesignatedInitExpr(DesignatedInitExpr *E) {
+  void VisitDesignatedInitExpr(PTR(DesignatedInitExpr) E) {
     // Only the actual initializer matters; the designators are all constant
     // expressions.
     return this->Visit(E->getInit());
   }
 
-  void VisitCXXTypeidExpr(CXXTypeidExpr *E) {
+  void VisitCXXTypeidExpr(PTR(CXXTypeidExpr) E) {
     if (E->isPotentiallyEvaluated())
       return this->Visit(E->getExprOperand());
   }
 
-  void VisitCallExpr(CallExpr *CE) {
+  void VisitCallExpr(PTR(CallExpr) CE) {
     if (!CE->isUnevaluatedBuiltinCall(Context))
       return static_cast<ImplClass*>(this)->VisitExpr(CE);
   }
 
-  void VisitLambdaExpr(LambdaExpr *LE) {
+  void VisitLambdaExpr(PTR(LambdaExpr) LE) {
     // Only visit the capture initializers, and not the body.
     for (LambdaExpr::capture_init_iterator I = LE->capture_init_begin(),
                                            E = LE->capture_init_end();
@@ -94,11 +97,31 @@ public:
 
   /// \brief The basis case walks all of the children of the statement or
   /// expression, assuming they are all potentially evaluated.
-  void VisitStmt(Stmt *S) {
-    for (Stmt::child_range C = S->children(); C; ++C)
+  void VisitStmt(PTR(Stmt) S) {
+    for (auto C = S->children(); C; ++C)
       if (*C)
         this->Visit(*C);
   }
+
+#undef PTR
+};
+
+/// EvaluatedExprVisitor - This class visits 'Expr *'s
+template<typename ImplClass>
+class EvaluatedExprVisitor
+ : public EvaluatedExprVisitorBase<make_ptr, ImplClass> {
+public:
+  explicit EvaluatedExprVisitor(const ASTContext &Context) :
+    EvaluatedExprVisitorBase<make_ptr, ImplClass>(Context) { }
+};
+
+/// ConstEvaluatedExprVisitor - This class visits 'const Expr *'s.
+template<typename ImplClass>
+class ConstEvaluatedExprVisitor
+ : public EvaluatedExprVisitorBase<make_const_ptr, ImplClass> {
+public:
+  explicit ConstEvaluatedExprVisitor(const ASTContext &Context) :
+    EvaluatedExprVisitorBase<make_const_ptr, ImplClass>(Context) { }
 };
 
 }
diff --git a/include/clang/AST/Expr.h b/include/clang/AST/Expr.h
index a3be7d06c4b1..2a5b4c0f5ed0 100644
--- a/include/clang/AST/Expr.h
+++ b/include/clang/AST/Expr.h
@@ -598,7 +598,7 @@ public:
 
   /// \brief Determine whether this expression involves a call to any function
   /// that is not trivial.
-  bool hasNonTrivialCall(ASTContext &Ctx);
+  bool hasNonTrivialCall(const ASTContext &Ctx) const;
 
   /// EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded
   /// integer. This must be called on an expression that constant folds to an
@@ -2273,7 +2273,7 @@ public:
 
   /// \brief Returns \c true if this is a call to a builtin which does not
   /// evaluate side-effects within its arguments.
-  bool isUnevaluatedBuiltinCall(ASTContext &Ctx) const;
+  bool isUnevaluatedBuiltinCall(const ASTContext &Ctx) const;
 
   /// getCallReturnType - Get the return type of the call expr. This is not
   /// always the type of the expr itself, if the return type is a reference
@@ -4267,6 +4267,80 @@ public:
   }
 };
 
+/// \brief Represents a place-holder for an object not to be initialized by
+/// anything.
+///
+/// This only makes sense when it appears as part of an updater of a
+/// DesignatedInitUpdateExpr (see below). The base expression of a DIUE
+/// initializes a big object, and the NoInitExpr's mark the spots within the
+/// big object not to be overwritten by the updater.
+///
+/// \see DesignatedInitUpdateExpr
+class NoInitExpr : public Expr {
+public:
+  explicit NoInitExpr(QualType ty)
+    : Expr(NoInitExprClass, ty, VK_RValue, OK_Ordinary,
+           false, false, ty->isInstantiationDependentType(), false) { }
+
+  explicit NoInitExpr(EmptyShell Empty)
+    : Expr(NoInitExprClass, Empty) { }
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == NoInitExprClass;
+  }
+
+  SourceLocation getLocStart() const LLVM_READONLY { return SourceLocation(); }
+  SourceLocation getLocEnd() const LLVM_READONLY { return SourceLocation(); }
+
+  // Iterators
+  child_range children() { return child_range(); }
+};
+
+// In cases like:
+//   struct Q { int a, b, c; };
+//   Q *getQ();
+//   void foo() {
+//     struct A { Q q; } a = { *getQ(), .q.b = 3 };
+//   }
+//
+// We will have an InitListExpr for a, with type A, and then a
+// DesignatedInitUpdateExpr for "a.q" with type Q. The "base" for this DIUE
+// is the call expression *getQ(); the "updater" for the DIUE is ".q.b = 3"
+//
+class DesignatedInitUpdateExpr : public Expr {
+  // BaseAndUpdaterExprs[0] is the base expression;
+  // BaseAndUpdaterExprs[1] is an InitListExpr overwriting part of the base.
+  Stmt *BaseAndUpdaterExprs[2];
+
+public:
+  DesignatedInitUpdateExpr(const ASTContext &C, SourceLocation lBraceLoc,
+                           Expr *baseExprs, SourceLocation rBraceLoc);
+
+  explicit DesignatedInitUpdateExpr(EmptyShell Empty)
+    : Expr(DesignatedInitUpdateExprClass, Empty) { }
+
+  SourceLocation getLocStart() const LLVM_READONLY;
+  SourceLocation getLocEnd() const LLVM_READONLY;
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == DesignatedInitUpdateExprClass;
+  }
+
+  Expr *getBase() const { return cast<Expr>(BaseAndUpdaterExprs[0]); }
+  void setBase(Expr *Base) { BaseAndUpdaterExprs[0] = Base; }
+
+  InitListExpr *getUpdater() const {
+    return cast<InitListExpr>(BaseAndUpdaterExprs[1]);
+  }
+  void setUpdater(Expr *Updater) { BaseAndUpdaterExprs[1] = Updater; }
+
+  // Iterators
+  // children = the base and the updater
+  child_range children() {
+    return child_range(&BaseAndUpdaterExprs[0], &BaseAndUpdaterExprs[0] + 2);
+  }
+};
+
 /// \brief Represents an implicitly-generated value initialization of
 /// an object of a given type.
 ///
diff --git a/include/clang/AST/OpenMPClause.h b/include/clang/AST/OpenMPClause.h
index c8ecef8ce50c..386c8dd3ee94 100644
--- a/include/clang/AST/OpenMPClause.h
+++ b/include/clang/AST/OpenMPClause.h
@@ -1752,7 +1752,7 @@ public:
 
   StmtRange children() {
     return StmtRange(reinterpret_cast<Stmt **>(varlist_begin()),
-                     reinterpret_cast<Stmt **>(getFinals().end() + 2));
+                     reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   static bool classof(const OMPClause *T) {
@@ -1837,7 +1837,7 @@ public:
 
   StmtRange children() {
     return StmtRange(reinterpret_cast<Stmt **>(varlist_begin()),
-                     reinterpret_cast<Stmt **>(varlist_end() + 1));
+                     reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   static bool classof(const OMPClause *T) {
diff --git a/include/clang/AST/RecursiveASTVisitor.h b/include/clang/AST/RecursiveASTVisitor.h
index 95e0df3066b0..95d773073184 100644
--- a/include/clang/AST/RecursiveASTVisitor.h
+++ b/include/clang/AST/RecursiveASTVisitor.h
@@ -2234,9 +2234,11 @@ DEF_TRAVERSE_STMT(CXXThisExpr, {})
 DEF_TRAVERSE_STMT(CXXThrowExpr, {})
 DEF_TRAVERSE_STMT(UserDefinedLiteral, {})
 DEF_TRAVERSE_STMT(DesignatedInitExpr, {})
+DEF_TRAVERSE_STMT(DesignatedInitUpdateExpr, {})
 DEF_TRAVERSE_STMT(ExtVectorElementExpr, {})
 DEF_TRAVERSE_STMT(GNUNullExpr, {})
 DEF_TRAVERSE_STMT(ImplicitValueInitExpr, {})
+DEF_TRAVERSE_STMT(NoInitExpr, {})
 DEF_TRAVERSE_STMT(ObjCBoolLiteralExpr, {})
 DEF_TRAVERSE_STMT(ObjCEncodeExpr, {
   if (TypeSourceInfo *TInfo = S->getEncodedTypeSourceInfo())
@@ -2386,6 +2388,9 @@ DEF_TRAVERSE_STMT(OMPBarrierDirective,
 DEF_TRAVERSE_STMT(OMPTaskwaitDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 
+DEF_TRAVERSE_STMT(OMPTaskgroupDirective,
+                  { TRY_TO(TraverseOMPExecutableDirective(S)); })
+
 DEF_TRAVERSE_STMT(OMPFlushDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 
diff --git a/include/clang/AST/StmtOpenMP.h b/include/clang/AST/StmtOpenMP.h
index 5161eff0993b..63f295ddfec0 100644
--- a/include/clang/AST/StmtOpenMP.h
+++ b/include/clang/AST/StmtOpenMP.h
@@ -285,24 +285,23 @@ class OMPLoopDirective : public OMPExecutableDirective {
     CalcLastIterationOffset = 3,
     PreConditionOffset = 4,
     CondOffset = 5,
-    SeparatedCondOffset = 6,
-    InitOffset = 7,
-    IncOffset = 8,
+    InitOffset = 6,
+    IncOffset = 7,
     // The '...End' enumerators do not correspond to child expressions - they
     // specify the offset to the end (and start of the following counters/
     // updates/finals arrays).
-    DefaultEnd = 9,
+    DefaultEnd = 8,
     // The following 7 exprs are used by worksharing loops only.
-    IsLastIterVariableOffset = 9,
-    LowerBoundVariableOffset = 10,
-    UpperBoundVariableOffset = 11,
-    StrideVariableOffset = 12,
-    EnsureUpperBoundOffset = 13,
-    NextLowerBoundOffset = 14,
-    NextUpperBoundOffset = 15,
+    IsLastIterVariableOffset = 8,
+    LowerBoundVariableOffset = 9,
+    UpperBoundVariableOffset = 10,
+    StrideVariableOffset = 11,
+    EnsureUpperBoundOffset = 12,
+    NextLowerBoundOffset = 13,
+    NextUpperBoundOffset = 14,
     // Offset to the end (and start of the following counters/updates/finals
     // arrays) for worksharing loop directives.
-    WorksharingEnd = 16,
+    WorksharingEnd = 15,
   };
 
   /// \brief Get the counters storage.
@@ -374,9 +373,8 @@ protected:
   void setPreCond(Expr *PC) {
     *std::next(child_begin(), PreConditionOffset) = PC;
   }
-  void setCond(Expr *Cond, Expr *SeparatedCond) {
+  void setCond(Expr *Cond) {
     *std::next(child_begin(), CondOffset) = Cond;
-    *std::next(child_begin(), SeparatedCondOffset) = SeparatedCond;
   }
   void setInit(Expr *Init) { *std::next(child_begin(), InitOffset) = Init; }
   void setInc(Expr *Inc) { *std::next(child_begin(), IncOffset) = Inc; }
@@ -435,8 +433,6 @@ public:
     Expr *PreCond;
     /// \brief Loop condition.
     Expr *Cond;
-    /// \brief A condition with 1 iteration separated.
-    Expr *SeparatedCond;
     /// \brief Loop iteration variable init.
     Expr *Init;
     /// \brief Loop increment.
@@ -467,8 +463,7 @@ public:
     bool builtAll() {
       return IterationVarRef != nullptr && LastIteration != nullptr &&
              NumIterations != nullptr && PreCond != nullptr &&
-             Cond != nullptr && SeparatedCond != nullptr && Init != nullptr &&
-             Inc != nullptr;
+             Cond != nullptr && Init != nullptr && Inc != nullptr;
     }
 
     /// \brief Initialize all the fields to null.
@@ -479,7 +474,6 @@ public:
       CalcLastIteration = nullptr;
       PreCond = nullptr;
       Cond = nullptr;
-      SeparatedCond = nullptr;
       Init = nullptr;
       Inc = nullptr;
       IL = nullptr;
@@ -519,10 +513,9 @@ public:
     return const_cast<Expr *>(reinterpret_cast<const Expr *>(
         *std::next(child_begin(), PreConditionOffset)));
   }
-  Expr *getCond(bool SeparateIter) const {
-    return const_cast<Expr *>(reinterpret_cast<const Expr *>(
-        *std::next(child_begin(),
-                   (SeparateIter ? SeparatedCondOffset : CondOffset))));
+  Expr *getCond() const {
+    return const_cast<Expr *>(
+        reinterpret_cast<const Expr *>(*std::next(child_begin(), CondOffset)));
   }
   Expr *getInit() const {
     return const_cast<Expr *>(
@@ -1462,6 +1455,53 @@ public:
   }
 };
 
+/// \brief This represents '#pragma omp taskgroup' directive.
+///
+/// \code
+/// #pragma omp taskgroup
+/// \endcode
+///
+class OMPTaskgroupDirective : public OMPExecutableDirective {
+  friend class ASTStmtReader;
+  /// \brief Build directive with the given start and end location.
+  ///
+  /// \param StartLoc Starting location of the directive kind.
+  /// \param EndLoc Ending location of the directive.
+  ///
+  OMPTaskgroupDirective(SourceLocation StartLoc, SourceLocation EndLoc)
+      : OMPExecutableDirective(this, OMPTaskgroupDirectiveClass, OMPD_taskgroup,
+                               StartLoc, EndLoc, 0, 1) {}
+
+  /// \brief Build an empty directive.
+  ///
+  explicit OMPTaskgroupDirective()
+      : OMPExecutableDirective(this, OMPTaskgroupDirectiveClass, OMPD_taskgroup,
+                               SourceLocation(), SourceLocation(), 0, 1) {}
+
+public:
+  /// \brief Creates directive.
+  ///
+  /// \param C AST context.
+  /// \param StartLoc Starting location of the directive kind.
+  /// \param EndLoc Ending Location of the directive.
+  /// \param AssociatedStmt Statement, associated with the directive.
+  ///
+  static OMPTaskgroupDirective *Create(const ASTContext &C,
+                                       SourceLocation StartLoc,
+                                       SourceLocation EndLoc,
+                                       Stmt *AssociatedStmt);
+
+  /// \brief Creates an empty directive.
+  ///
+  /// \param C AST context.
+  ///
+  static OMPTaskgroupDirective *CreateEmpty(const ASTContext &C, EmptyShell);
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == OMPTaskgroupDirectiveClass;
+  }
+};
+
 /// \brief This represents '#pragma omp flush' directive.
 ///
 /// \code
diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
index 8cd29b7b917e..d903b9d8cbcf 100644
--- a/include/clang/AST/Type.h
+++ b/include/clang/AST/Type.h
@@ -1818,6 +1818,19 @@ public:
   /// checking. Should always return true.
   bool isLinkageValid() const;
 
+  /// Determine the nullability of the given type.
+  ///
+  /// Note that nullability is only captured as sugar within the type
+  /// system, not as part of the canonical type, so nullability will
+  /// be lost by canonicalization and desugaring.
+  Optional<NullabilityKind> getNullability(const ASTContext &context) const;
+
+  /// Determine whether the given type can have a nullability
+  /// specifier applied to it, i.e., if it is any kind of pointer type
+  /// or a dependent type that could instantiate to any kind of
+  /// pointer type.
+  bool canHaveNullability() const;
+
   const char *getTypeClassName() const;
 
   QualType getCanonicalTypeInternal() const {
@@ -3479,7 +3492,10 @@ public:
     attr_ptr32,
     attr_ptr64,
     attr_sptr,
-    attr_uptr
+    attr_uptr,
+    attr_nonnull,
+    attr_nullable,
+    attr_null_unspecified,
   };
 
 private:
@@ -3513,6 +3529,35 @@ public:
 
   bool isCallingConv() const;
 
+  llvm::Optional<NullabilityKind> getImmediateNullability() const;
+
+  /// Retrieve the attribute kind corresponding to the given
+  /// nullability kind.
+  static Kind getNullabilityAttrKind(NullabilityKind kind) {
+    switch (kind) {
+    case NullabilityKind::NonNull:
+      return attr_nonnull;
+     
+    case NullabilityKind::Nullable:
+      return attr_nullable;
+
+    case NullabilityKind::Unspecified:
+      return attr_null_unspecified;
+    }
+    llvm_unreachable("Unknown nullability kind.");
+  }
+
+  /// Strip off the top-level nullability annotation on the given
+  /// type, if it's there.
+  ///
+  /// \param T The type to strip. If the type is exactly an
+  /// AttributedType specifying nullability (without looking through
+  /// type sugar), the nullability is returned and this type changed
+  /// to the underlying modified type.
+  ///
+  /// \returns the top-level nullability, if present.
+  static Optional<NullabilityKind> stripOuterNullability(QualType &T);
+
   void Profile(llvm::FoldingSetNodeID &ID) {
     Profile(ID, getAttrKind(), ModifiedType, EquivalentType);
   }