[attributes] Add a family of OS_CONSUMED, OS_RETURNS and OS_RETURNS_RETAINED attributes

The addition adds three attributes for communicating ownership,
analogous to existing NS_ and CF_ attributes.
The attributes are meant to be used for communicating ownership of all
objects in XNU (Darwin kernel) and all of the kernel modules.
The ownership model there is very similar, but still different from the
Foundation model, so we think that introducing a new family of
attributes is appropriate.

The addition required a sizeable refactoring of the existing code for
CF_ and NS_ ownership attributes, due to tight coupling and the fact
that differentiating between the types was previously done using a
boolean.

Differential Revision: https://reviews.llvm.org/D54912

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@347947 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 279 insertions, 76 deletions

diff --git a/include/clang/Basic/Attr.td b/include/clang/Basic/Attr.td
index 5b52ba4f64..deeb1b73a3 100644
--- a/include/clang/Basic/Attr.td
+++ b/include/clang/Basic/Attr.td
@@ -812,19 +812,38 @@ def CFUnknownTransfer : InheritableAttr {
 def CFReturnsRetained : InheritableAttr {
   let Spellings = [Clang<"cf_returns_retained">];
 //  let Subjects = SubjectList<[ObjCMethod, ObjCProperty, Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def CFReturnsNotRetained : InheritableAttr {
   let Spellings = [Clang<"cf_returns_not_retained">];
 //  let Subjects = SubjectList<[ObjCMethod, ObjCProperty, Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def CFConsumed : InheritableParamAttr {
   let Spellings = [Clang<"cf_consumed">];
   let Subjects = SubjectList<[ParmVar]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
+}
+
+// OSObject-based attributes.
+def OSConsumed : InheritableParamAttr {
+  let Spellings = [Clang<"os_consumed">];
+  let Subjects = SubjectList<[ParmVar]>;
+  let Documentation = [RetainBehaviorDocs];
+}
+
+def OSReturnsRetained : InheritableAttr {
+  let Spellings = [Clang<"os_returns_retained">];
+  let Subjects = SubjectList<[Function, ObjCMethod, ObjCProperty]>;
+  let Documentation = [RetainBehaviorDocs];
+}
+
+def OSReturnsNotRetained : InheritableAttr {
+  let Spellings = [Clang<"os_returns_not_retained">];
+  let Subjects = SubjectList<[Function, ObjCMethod, ObjCProperty]>;
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def Cleanup : InheritableAttr {
@@ -1612,19 +1631,19 @@ def ObjCBridgeRelated : InheritableAttr {
 def NSReturnsRetained : DeclOrTypeAttr {
   let Spellings = [Clang<"ns_returns_retained">];
 //  let Subjects = SubjectList<[ObjCMethod, ObjCProperty, Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def NSReturnsNotRetained : InheritableAttr {
   let Spellings = [Clang<"ns_returns_not_retained">];
 //  let Subjects = SubjectList<[ObjCMethod, ObjCProperty, Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def NSReturnsAutoreleased : InheritableAttr {
   let Spellings = [Clang<"ns_returns_autoreleased">];
 //  let Subjects = SubjectList<[ObjCMethod, ObjCProperty, Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [RetainBehaviorDocs];
 }
 
 def NSConsumesSelf : InheritableAttr {
diff --git a/include/clang/Basic/AttrDocs.td b/include/clang/Basic/AttrDocs.td
index 203ae82719..1336d28e45 100644
--- a/include/clang/Basic/AttrDocs.td
+++ b/include/clang/Basic/AttrDocs.td
@@ -847,6 +847,51 @@ Query for this feature with ``__has_attribute(objc_method_family)``.
   }];
 }
 
+def RetainBehaviorDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+The behavior of a function with respect to reference counting for Foundation
+(Objective-C), CoreFoundation (C) and OSObject (C++) is determined by a naming
+convention (e.g. functions starting with "get" are assumed to return at
+``+0``).
+
+It can be overriden using a family of the following attributes.  In
+Objective-C, the annotation ``__attribute__((ns_returns_retained))`` applied to
+a function communicates that the object is returned at ``+1``, and the caller
+is responsible for freeing it.
+Similiarly, the annotation ``__attribute__((ns_returns_not_retained))``
+specifies that the object is returned at ``+0`` and the ownership remains with
+the callee.
+Additionally, parameters can have an annotation
+``__attribute__((ns_consumed))``, which specifies that passing an owned object
+as that parameter effectively transfers the ownership, and the caller is no
+longer responsible for it.
+These attributes affect code generation when interacting with ARC code, and
+they are used by the Clang Static Analyzer.
+
+In C programs using CoreFoundation, a similar set of attributes:
+``__attribute__((cf_returns_not_retained))``,
+``__attribute__((cf_returns_retained))`` and ``__attribute__((cf_consumed))``
+have the same respective semantics when applied to CoreFoundation objects.
+These attributes affect code generation when interacting with ARC code, and
+they are used by the Clang Static Analyzer.
+
+Finally, in C++ interacting with XNU kernel (objects inheriting from OSObject),
+the same attribute family is present:
+``__attribute__((os_returns_not_retained))``,
+``__attribute__((os_returns_retained))`` and ``__attribute__((os_consumed))``,
+with the same respective semantics.
+These attributes are also used by the Clang Static Analyzer.
+
+The family of attributes ``X_returns_X_retained`` can be added to functions,
+C++ methods, and Objective-C methods and properties.
+Attributes ``X_consumed`` can be added to parameters of methods, functions,
+and Objective-C methods.
+  }];
+}
+
+
+
 def NoDebugDocs : Documentation {
   let Category = DocCatVariable;
   let Content = [{
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 794b8f8806..f9e9cde076 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -8544,9 +8544,9 @@ public:
   void AddParameterABIAttr(SourceRange AttrRange, Decl *D,
                            ParameterABI ABI, unsigned SpellingListIndex);
 
-  void AddNSConsumedAttr(SourceRange AttrRange, Decl *D,
-                         unsigned SpellingListIndex, bool isNSConsumed,
-                         bool isTemplateInstantiation);
+  enum class RetainOwnershipKind {NS, CF, OS};
+  void AddXConsumedAttr(Decl *D, SourceRange SR, unsigned SpellingIndex,
+                        RetainOwnershipKind K, bool IsTemplateInstantiation);
 
   bool checkNSReturnsRetainedReturnType(SourceLocation loc, QualType type);
 
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index be662b9b91..a2520c03cb 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -392,9 +392,49 @@ bool Sema::checkStringLiteralArgumentAttr(const ParsedAttr &AL, unsigned ArgNum,
 /// Applies the given attribute to the Decl without performing any
 /// additional semantic checking.
 template <typename AttrType>
+static void handleSimpleAttribute(Sema &S, Decl *D, SourceRange SR,
+                                  unsigned SpellingIndex) {
+  D->addAttr(::new (S.Context) AttrType(SR, S.Context, SpellingIndex));
+}
+
+template <typename AttrType>
 static void handleSimpleAttribute(Sema &S, Decl *D, const ParsedAttr &AL) {
-  D->addAttr(::new (S.Context) AttrType(AL.getRange(), S.Context,
-                                        AL.getAttributeSpellingListIndex()));
+  handleSimpleAttribute<AttrType>(S, D, AL.getRange(),
+                                  AL.getAttributeSpellingListIndex());
+}
+
+
+template <typename... DiagnosticArgs>
+static const Sema::SemaDiagnosticBuilder&
+appendDiagnostics(const Sema::SemaDiagnosticBuilder &Bldr) {
+  return Bldr;
+}
+
+template <typename T, typename... DiagnosticArgs>
+static const Sema::SemaDiagnosticBuilder&
+appendDiagnostics(const Sema::SemaDiagnosticBuilder &Bldr, T &&ExtraArg,
+                  DiagnosticArgs &&... ExtraArgs) {
+  return appendDiagnostics(Bldr << std::forward<T>(ExtraArg),
+                           std::forward<DiagnosticArgs>(ExtraArgs)...);
+}
+
+/// Add an attribute {@code AttrType} to declaration {@code D},
+/// provided the given {@code Check} function returns {@code true}
+/// on type of {@code D}.
+/// If check does not pass, emit diagnostic {@code DiagID},
+/// passing in all parameters specified in {@code ExtraArgs}.
+template <typename AttrType, typename... DiagnosticArgs>
+static void
+handleSimpleAttributeWithCheck(Sema &S, ValueDecl *D, SourceRange SR,
+                               unsigned SpellingIndex,
+                               llvm::function_ref<bool(QualType)> Check,
+                               unsigned DiagID, DiagnosticArgs... ExtraArgs) {
+  if (!Check(D->getType())) {
+    Sema::SemaDiagnosticBuilder DB = S.Diag(D->getBeginLoc(), DiagID);
+    appendDiagnostics(DB, std::forward<DiagnosticArgs>(ExtraArgs)...);
+    return;
+  }
+  handleSimpleAttribute<AttrType>(S, D, SR, SpellingIndex);
 }
 
 template <typename AttrType>
@@ -4711,58 +4751,70 @@ static void handleXRayLogArgsAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
 //===----------------------------------------------------------------------===//
 // Checker-specific attribute handlers.
 //===----------------------------------------------------------------------===//
-
 static bool isValidSubjectOfNSReturnsRetainedAttribute(QualType QT) {
   return QT->isDependentType() || QT->isObjCRetainableType();
 }
 
-static bool isValidSubjectOfNSAttribute(Sema &S, QualType QT) {
+static bool isValidSubjectOfNSAttribute(QualType QT) {
   return QT->isDependentType() || QT->isObjCObjectPointerType() ||
-         S.Context.isObjCNSObjectType(QT);
+         QT->isObjCNSObjectType();
 }
 
-static bool isValidSubjectOfCFAttribute(Sema &S, QualType QT) {
+static bool isValidSubjectOfCFAttribute(QualType QT) {
   return QT->isDependentType() || QT->isPointerType() ||
-         isValidSubjectOfNSAttribute(S, QT);
+         isValidSubjectOfNSAttribute(QT);
 }
 
-static void handleNSConsumedAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
-  S.AddNSConsumedAttr(AL.getRange(), D, AL.getAttributeSpellingListIndex(),
-                      AL.getKind() == ParsedAttr::AT_NSConsumed,
-                      /*template instantiation*/ false);
+static bool isValidSubjectOfOSAttribute(QualType QT) {
+  return QT->isDependentType() || QT->isPointerType();
 }
 
-void Sema::AddNSConsumedAttr(SourceRange AttrRange, Decl *D,
-                             unsigned SpellingIndex, bool IsNSConsumed,
-                             bool IsTemplateInstantiation) {
-  const auto *Param = cast<ParmVarDecl>(D);
-  bool TypeOK;
-
-  if (IsNSConsumed)
-    TypeOK = isValidSubjectOfNSAttribute(*this, Param->getType());
-  else
-    TypeOK = isValidSubjectOfCFAttribute(*this, Param->getType());
+void Sema::AddXConsumedAttr(Decl *D, SourceRange SR, unsigned SpellingIndex,
+                            RetainOwnershipKind K,
+                            bool IsTemplateInstantiation) {
+  ValueDecl *VD = cast<ValueDecl>(D);
+  switch (K) {
+  case RetainOwnershipKind::OS:
+    handleSimpleAttributeWithCheck<OSConsumedAttr>(
+        *this, VD, SR, SpellingIndex, &isValidSubjectOfOSAttribute,
+        diag::warn_ns_attribute_wrong_parameter_type,
+        /*ExtraArgs=*/SR, "os_consumed", /*pointers*/ 1);
+    return;
+  case RetainOwnershipKind::NS:
+    handleSimpleAttributeWithCheck<NSConsumedAttr>(
+        *this, VD, SR, SpellingIndex, &isValidSubjectOfNSAttribute,
 
-  if (!TypeOK) {
-    // These attributes are normally just advisory, but in ARC, ns_consumed
-    // is significant.  Allow non-dependent code to contain inappropriate
-    // attributes even in ARC, but require template instantiations to be
-    // set up correctly.
-    Diag(D->getBeginLoc(), (IsTemplateInstantiation && IsNSConsumed &&
-                                    getLangOpts().ObjCAutoRefCount
-                                ? diag::err_ns_attribute_wrong_parameter_type
-                                : diag::warn_ns_attribute_wrong_parameter_type))
-        << AttrRange << (IsNSConsumed ? "ns_consumed" : "cf_consumed")
-        << (IsNSConsumed ? /*objc pointers*/ 0 : /*cf pointers*/ 1);
+        // These attributes are normally just advisory, but in ARC, ns_consumed
+        // is significant.  Allow non-dependent code to contain inappropriate
+        // attributes even in ARC, but require template instantiations to be
+        // set up correctly.
+        ((IsTemplateInstantiation && getLangOpts().ObjCAutoRefCount)
+             ? diag::err_ns_attribute_wrong_parameter_type
+             : diag::warn_ns_attribute_wrong_parameter_type),
+        /*ExtraArgs=*/SR, "ns_consumed", /*objc pointers*/ 0);
+    return;
+  case RetainOwnershipKind::CF:
+    handleSimpleAttributeWithCheck<CFConsumedAttr>(
+        *this, VD, SR, SpellingIndex,
+        &isValidSubjectOfCFAttribute,
+        diag::warn_ns_attribute_wrong_parameter_type,
+        /*ExtraArgs=*/SR, "cf_consumed", /*pointers*/1);
     return;
   }
+}
 
-  if (IsNSConsumed)
-    D->addAttr(::new (Context)
-                   NSConsumedAttr(AttrRange, Context, SpellingIndex));
-  else
-    D->addAttr(::new (Context)
-                   CFConsumedAttr(AttrRange, Context, SpellingIndex));
+static Sema::RetainOwnershipKind
+parsedAttrToRetainOwnershipKind(const ParsedAttr &AL) {
+  switch (AL.getKind()) {
+  case ParsedAttr::AT_CFConsumed:
+    return Sema::RetainOwnershipKind::CF;
+  case ParsedAttr::AT_OSConsumed:
+    return Sema::RetainOwnershipKind::OS;
+  case ParsedAttr::AT_NSConsumed:
+    return Sema::RetainOwnershipKind::NS;
+  default:
+    llvm_unreachable("Wrong argument supplied");
+  }
 }
 
 bool Sema::checkNSReturnsRetainedReturnType(SourceLocation Loc, QualType QT) {
@@ -4774,24 +4826,26 @@ bool Sema::checkNSReturnsRetainedReturnType(SourceLocation Loc, QualType QT) {
   return true;
 }
 
-static void handleNSReturnsRetainedAttr(Sema &S, Decl *D,
+static void handleXReturnsXRetainedAttr(Sema &S, Decl *D,
                                         const ParsedAttr &AL) {
   QualType ReturnType;
 
-  if (const auto *MD = dyn_cast<ObjCMethodDecl>(D))
+  if (const auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
     ReturnType = MD->getReturnType();
-  else if (S.getLangOpts().ObjCAutoRefCount && hasDeclarator(D) &&
-           (AL.getKind() == ParsedAttr::AT_NSReturnsRetained))
+  } else if (S.getLangOpts().ObjCAutoRefCount && hasDeclarator(D) &&
+             (AL.getKind() == ParsedAttr::AT_NSReturnsRetained)) {
     return; // ignore: was handled as a type attribute
-  else if (const auto *PD = dyn_cast<ObjCPropertyDecl>(D))
+  } else if (const auto *PD = dyn_cast<ObjCPropertyDecl>(D)) {
     ReturnType = PD->getType();
-  else if (const auto *FD = dyn_cast<FunctionDecl>(D))
+  } else if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
     ReturnType = FD->getReturnType();
-  else if (const auto *Param = dyn_cast<ParmVarDecl>(D)) {
+  } else if (const auto *Param = dyn_cast<ParmVarDecl>(D)) {
+    // Attributes on parameters are used for out-parameters,
+    // passed as pointers-to-pointers.
     ReturnType = Param->getType()->getPointeeType();
     if (ReturnType.isNull()) {
       S.Diag(D->getBeginLoc(), diag::warn_ns_attribute_wrong_parameter_type)
-          << AL << /*pointer-to-CF*/ 2 << AL.getRange();
+          << AL << /*pointer-to-CF-pointer*/ 2 << AL.getRange();
       return;
     }
   } else if (AL.isUsedAsTypeAttr()) {
@@ -4803,6 +4857,8 @@ static void handleNSReturnsRetainedAttr(Sema &S, Decl *D,
     case ParsedAttr::AT_NSReturnsRetained:
     case ParsedAttr::AT_NSReturnsAutoreleased:
     case ParsedAttr::AT_NSReturnsNotRetained:
+    case ParsedAttr::AT_OSReturnsRetained:
+    case ParsedAttr::AT_OSReturnsNotRetained:
       ExpectedDeclKind = ExpectedFunctionOrMethod;
       break;
 
@@ -4827,13 +4883,19 @@ static void handleNSReturnsRetainedAttr(Sema &S, Decl *D,
 
   case ParsedAttr::AT_NSReturnsAutoreleased:
   case ParsedAttr::AT_NSReturnsNotRetained:
-    TypeOK = isValidSubjectOfNSAttribute(S, ReturnType);
+    TypeOK = isValidSubjectOfNSAttribute(ReturnType);
     Cf = false;
     break;
 
   case ParsedAttr::AT_CFReturnsRetained:
   case ParsedAttr::AT_CFReturnsNotRetained:
-    TypeOK = isValidSubjectOfCFAttribute(S, ReturnType);
+    TypeOK = isValidSubjectOfCFAttribute(ReturnType);
+    Cf = true;
+    break;
+
+  case ParsedAttr::AT_OSReturnsRetained:
+  case ParsedAttr::AT_OSReturnsNotRetained:
+    TypeOK = isValidSubjectOfOSAttribute(ReturnType);
     Cf = true;
     break;
   }
@@ -4866,24 +4928,25 @@ static void handleNSReturnsRetainedAttr(Sema &S, Decl *D,
     default:
       llvm_unreachable("invalid ownership attribute");
     case ParsedAttr::AT_NSReturnsAutoreleased:
-      D->addAttr(::new (S.Context) NSReturnsAutoreleasedAttr(
-          AL.getRange(), S.Context, AL.getAttributeSpellingListIndex()));
+      handleSimpleAttribute<NSReturnsAutoreleasedAttr>(S, D, AL);
       return;
     case ParsedAttr::AT_CFReturnsNotRetained:
-      D->addAttr(::new (S.Context) CFReturnsNotRetainedAttr(
-          AL.getRange(), S.Context, AL.getAttributeSpellingListIndex()));
+      handleSimpleAttribute<CFReturnsNotRetainedAttr>(S, D, AL);
       return;
     case ParsedAttr::AT_NSReturnsNotRetained:
-      D->addAttr(::new (S.Context) NSReturnsNotRetainedAttr(
-          AL.getRange(), S.Context, AL.getAttributeSpellingListIndex()));
+      handleSimpleAttribute<NSReturnsNotRetainedAttr>(S, D, AL);
       return;
     case ParsedAttr::AT_CFReturnsRetained:
-      D->addAttr(::new (S.Context) CFReturnsRetainedAttr(
-          AL.getRange(), S.Context, AL.getAttributeSpellingListIndex()));
+      handleSimpleAttribute<CFReturnsRetainedAttr>(S, D, AL);
       return;
     case ParsedAttr::AT_NSReturnsRetained:
-      D->addAttr(::new (S.Context) NSReturnsRetainedAttr(
-          AL.getRange(), S.Context, AL.getAttributeSpellingListIndex()));
+      handleSimpleAttribute<NSReturnsRetainedAttr>(S, D, AL);
+      return;
+    case ParsedAttr::AT_OSReturnsRetained:
+      handleSimpleAttribute<OSReturnsRetainedAttr>(S, D, AL);
+      return;
+    case ParsedAttr::AT_OSReturnsNotRetained:
+      handleSimpleAttribute<OSReturnsNotRetainedAttr>(S, D, AL);
       return;
   };
 }
@@ -6337,17 +6400,22 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
     break;
   case ParsedAttr::AT_CFConsumed:
   case ParsedAttr::AT_NSConsumed:
-    handleNSConsumedAttr(S, D, AL);
+  case ParsedAttr::AT_OSConsumed:
+    S.AddXConsumedAttr(D, AL.getRange(), AL.getAttributeSpellingListIndex(),
+                     parsedAttrToRetainOwnershipKind(AL),
+                     /*IsTemplateInstantiation=*/false);
     break;
   case ParsedAttr::AT_NSConsumesSelf:
     handleSimpleAttribute<NSConsumesSelfAttr>(S, D, AL);
     break;
   case ParsedAttr::AT_NSReturnsAutoreleased:
   case ParsedAttr::AT_NSReturnsNotRetained:
-  case ParsedAttr::AT_CFReturnsNotRetained:
   case ParsedAttr::AT_NSReturnsRetained:
+  case ParsedAttr::AT_CFReturnsNotRetained:
   case ParsedAttr::AT_CFReturnsRetained:
-    handleNSReturnsRetainedAttr(S, D, AL);
+  case ParsedAttr::AT_OSReturnsNotRetained:
+  case ParsedAttr::AT_OSReturnsRetained:
+    handleXReturnsXRetainedAttr(S, D, AL);
     break;
   case ParsedAttr::AT_WorkGroupSizeHint:
     handleWorkGroupSize<WorkGroupSizeHintAttr>(S, D, AL);
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 4f7ecdfcdf..f810c4eb31 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -365,6 +365,20 @@ void Sema::InstantiateAttrsForDecl(
   }
 }
 
+static Sema::RetainOwnershipKind
+attrToRetainOwnershipKind(const Attr *A) {
+  switch (A->getKind()) {
+  case clang::attr::CFConsumed:
+    return Sema::RetainOwnershipKind::CF;
+  case clang::attr::OSConsumed:
+    return Sema::RetainOwnershipKind::OS;
+  case clang::attr::NSConsumed:
+    return Sema::RetainOwnershipKind::NS;
+  default:
+    llvm_unreachable("Wrong argument supplied");
+  }
+}
+
 void Sema::InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
                             const Decl *Tmpl, Decl *New,
                             LateInstantiatedAttrVec *LateAttrs,
@@ -438,11 +452,12 @@ void Sema::InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
       continue;
     }
 
-    if (isa<NSConsumedAttr>(TmplAttr) || isa<CFConsumedAttr>(TmplAttr)) {
-      AddNSConsumedAttr(TmplAttr->getRange(), New,
-                        TmplAttr->getSpellingListIndex(),
-                        isa<NSConsumedAttr>(TmplAttr),
-                        /*template instantiation*/ true);
+    if (isa<NSConsumedAttr>(TmplAttr) || isa<OSConsumedAttr>(TmplAttr) ||
+        isa<CFConsumedAttr>(TmplAttr)) {
+      AddXConsumedAttr(New, TmplAttr->getRange(),
+                       TmplAttr->getSpellingListIndex(),
+                       attrToRetainOwnershipKind(TmplAttr),
+                       /*template instantiation=*/true);
       continue;
     }
 
diff --git a/test/Misc/pragma-attribute-supported-attributes-list.test b/test/Misc/pragma-attribute-supported-attributes-list.test
index 0aa923de7d..38af02be29 100644
--- a/test/Misc/pragma-attribute-supported-attributes-list.test
+++ b/test/Misc/pragma-attribute-supported-attributes-list.test
@@ -2,7 +2,7 @@
 
 // The number of supported attributes should never go down!
 
-// CHECK: #pragma clang attribute supports 130 attributes:
+// CHECK: #pragma clang attribute supports 132 attributes:
 // CHECK-NEXT: AMDGPUFlatWorkGroupSize (SubjectMatchRule_function)
 // CHECK-NEXT: AMDGPUNumSGPR (SubjectMatchRule_function)
 // CHECK-NEXT: AMDGPUNumVGPR (SubjectMatchRule_function)
@@ -85,6 +85,9 @@
 // CHECK-NEXT: NoThreadSafetyAnalysis (SubjectMatchRule_function)
 // CHECK-NEXT: NoThrow (SubjectMatchRule_function)
 // CHECK-NEXT: NotTailCalled (SubjectMatchRule_function)
+// CHECK-NEXT: OSConsumed (SubjectMatchRule_variable_is_parameter)
+// CHECK-NEXT: OSReturnsNotRetained (SubjectMatchRule_function, SubjectMatchRule_objc_method)
+// CHECK-NEXT: OSReturnsRetained (SubjectMatchRule_function, SubjectMatchRule_objc_method)
 // CHECK-NEXT: ObjCBoxable (SubjectMatchRule_record)
 // CHECK-NEXT: ObjCBridge (SubjectMatchRule_record, SubjectMatchRule_type_alias)
 // CHECK-NEXT: ObjCBridgeMutable (SubjectMatchRule_record)
diff --git a/test/Sema/attr-osobject.cpp b/test/Sema/attr-osobject.cpp
new file mode 100644
index 0000000000..fe9ed6b912
--- /dev/null
+++ b/test/Sema/attr-osobject.cpp
@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+struct S {
+  __attribute__((os_returns_retained)) S* method_returns_retained() {
+    return nullptr;
+  }
+};
+__attribute__((os_returns_retained)) S *ret_retained() {
+  return nullptr;
+}
+
+__attribute__((os_returns_retained)) S ret_retained_value() { // expected-warning{{'os_returns_retained' attribute only applies to functions that return a pointer}}
+  return {};
+}
+
+__attribute__((os_returns_not_retained)) S *ret_not_retained() {
+  return nullptr;
+}
+
+__attribute__((os_returns_not_retained)) S ret_not_retained_value() { // expected-warning{{'os_returns_not_retained' attribute only applies to functions that return a pointer}}
+  return {};
+}
+
+void accept_consumed_arg(__attribute__((os_consumed)) S *arg) {}
+
+void accept_consumed_arg_by_value(__attribute__((os_consumed)) S arg) {} // expected-warning{{os_consumed attribute only applies to pointer parameters}}
+
+void accept_consumed_arg_no_extra_arg(__attribute__((os_consumed(10))) S *arg) {} // expected-error{{'os_consumed' attribute takes no arguments}}
+
+struct __attribute__((os_consumed)) NoAttrOnStruct {}; // expected-warning{{'os_consumed' attribute only applies to parameters}}
+
+__attribute__((os_returns_retained(10))) S* returns_retained_no_extra_arg() { // expected-error{{'os_returns_retained' attribute takes no arguments}}
+  return nullptr;
+}
+
+struct __attribute__((os_returns_retained)) NoRetainAttrOnStruct {}; // expected-warning{{'os_returns_retained' attribute only applies to functions, Objective-C methods, and Objective-C properties}}
+
+__attribute__((os_returns_not_retained(10))) S* os_returns_no_retained_no_extra_args( S *arg) { // expected-error{{'os_returns_not_retained' attribute takes no arguments}}
+  return nullptr;
+} 
+
+struct __attribute__((os_returns_not_retained)) NoNotRetainedAttrOnStruct {}; // expected-warning{{'os_returns_not_retained' attribute only applies to functions, Objective-C methods, and Objective-C properties}}
diff --git a/test/Sema/attr-osobject.mm b/test/Sema/attr-osobject.mm
new file mode 100644
index 0000000000..dbd9122a8f
--- /dev/null
+++ b/test/Sema/attr-osobject.mm
@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+// expected-no-diagnostics
+
+struct S {};
+
+@interface I
+  @property (readonly) S* prop __attribute__((os_returns_retained));
+  - (S*) generateS __attribute__((os_returns_retained));
+  - (void) takeS:(S*) __attribute__((os_consumed)) s;
+@end