Sema: support __declspec(dll*) on ObjC interfaces

Extend the __declspec(dll*) attribute to cover ObjC interfaces.  This was
requested by Microsoft for their ObjC support.  Cover both import and export.
This only adds the semantic analysis portion of the support, code-generation
still remains outstanding.  Add some basic initial documentation on the
attributes that were previously empty.  Tweak the previous tests to use the
relative expected-warnings to make the tests easier to read.

llvm-svn: 275610

clang/include/clang/Basic/Attr.td

@@ -2087,14 +2087,14 @@ def MSStruct : InheritableAttr {
 
 def DLLExport : InheritableAttr, TargetSpecificAttr<TargetWindows> {
   let Spellings = [Declspec<"dllexport">, GCC<"dllexport">];
-  let Subjects = SubjectList<[Function, Var, CXXRecord]>;
-  let Documentation = [Undocumented];
+  let Subjects = SubjectList<[Function, Var, CXXRecord, ObjCInterface]>;
+  let Documentation = [DLLExportDocs];
 }
 
 def DLLImport : InheritableAttr, TargetSpecificAttr<TargetWindows> {
   let Spellings = [Declspec<"dllimport">, GCC<"dllimport">];
-  let Subjects = SubjectList<[Function, Var, CXXRecord]>;
-  let Documentation = [Undocumented];
+  let Subjects = SubjectList<[Function, Var, CXXRecord, ObjCInterface]>;
+  let Documentation = [DLLImportDocs];
 }
 
 def SelectAny : InheritableAttr {

clang/include/clang/Basic/AttrDocs.td

@@ -67,6 +67,34 @@ TLS models are mutually exclusive.
   }];
 }
 
+def DLLExportDocs : Documentation {
+  let Category = DocCatVariable;
+  let Content = [{
+The ``__declspec(dllexport)`` attribute declares a variable, function, or
+Objective-C interface to be exported from the module.  It is available under the
+``-fdeclspec`` flag for compatibility with various compilers.  The primary use
+is for COFF object files which explicitly specify what interfaces are available
+for external use.  See the dllexport_ documentation on MSDN for more
+information.
+
+.. _dllexport: https://msdn.microsoft.com/en-us/library/3y1sfaz2.aspx
+  }];
+}
+
+def DLLImportDocs : Documentation {
+  let Category = DocCatVariable;
+  let Content = [{
+The ``__declspec(dllimport)`` attribute declares a variable, function, or
+Objective-C interface to be imported from an external module.  It is available
+under the ``-fdeclspec`` flag for compatibility with various compilers.  The
+primary use is for COFF object files which explicitly specify what interfaces
+are imported from external modules.  See the dllimport_ documentation on MSDN
+for more information.
+
+.. _dllimport: https://msdn.microsoft.com/en-us/library/3y1sfaz2.aspx
+  }];
+}
+
 def ThreadDocs : Documentation {
   let Category = DocCatVariable;
   let Content = [{

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -2503,7 +2503,9 @@ def err_ifunc_resolver_params : Error<
   "ifunc resolver function must have no parameters">;
 def warn_attribute_wrong_decl_type : Warning<
   "%0 attribute only applies to %select{functions|unions|"
-  "variables and functions|functions and methods|parameters|"
+  "variables and functions|"
+  "functions, variables, and Objective-C interfaces|"
+  "functions and methods|parameters|"
   "functions, methods and blocks|functions, methods, and classes|"
   "functions, methods, and parameters|classes|enums|variables|methods|"
   "fields and global variables|structs|parameters and typedefs|variables and typedefs|"
@@ -2511,7 +2513,9 @@ def warn_attribute_wrong_decl_type : Warning<
   "types and namespaces|Objective-C interfaces|methods and properties|"
   "struct or union|struct, union or class|types|"
   "Objective-C instance methods|init methods of interface or class extension declarations|"
-  "variables, functions and classes|Objective-C protocols|"
+  "variables, functions and classes|"
+  "functions, variables, classes, and Objective-C interfaces|"
+  "Objective-C protocols|"
   "functions and global variables|structs, unions, and typedefs|structs and typedefs|"
   "interface or protocol declarations|kernel functions|non-K&R-style functions|"
   "variables, enums, fields and typedefs|functions, methods, enums, and classes|"

clang/include/clang/Sema/AttributeList.h

@@ -869,6 +869,7 @@ enum AttributeDeclKind {
   ExpectedFunction,
   ExpectedUnion,
   ExpectedVariableOrFunction,
+  ExpectedFunctionVariableOrObjCInterface,
   ExpectedFunctionOrMethod,
   ExpectedParameter,
   ExpectedFunctionMethodOrBlock,
@@ -894,6 +895,7 @@ enum AttributeDeclKind {
   ExpectedObjCInstanceMethod,
   ExpectedObjCInterfaceDeclInitMethod,
   ExpectedFunctionVariableOrClass,
+  ExpectedFunctionVariableClassOrObjCInterface,
   ExpectedObjectiveCProtocol,
   ExpectedFunctionGlobalVarMethodOrProperty,
   ExpectedStructOrUnionOrTypedef,

clang/test/Sema/dllexport.c

@@ -4,12 +4,18 @@
 // RUN: %clang_cc1 -triple x86_64-mingw32 -fsyntax-only -fms-extensions -verify -std=c99 %s
 
 // Invalid usage.
-__declspec(dllexport) typedef int typedef1; // expected-warning{{'dllexport' attribute only applies to variables and functions}}
-typedef __declspec(dllexport) int typedef2; // expected-warning{{'dllexport' attribute only applies to variables and functions}}
-typedef int __declspec(dllexport) typedef3; // expected-warning{{'dllexport' attribute only applies to variables and functions}}
-typedef __declspec(dllexport) void (*FunTy)(); // expected-warning{{'dllexport' attribute only applies to variables and functions}}
-enum __declspec(dllexport) Enum { EnumVal }; // expected-warning{{'dllexport' attribute only applies to variables and functions}}
-struct __declspec(dllexport) Record {}; // expected-warning{{'dllexport' attribute only applies to variables and functions}}
+__declspec(dllexport) typedef int typedef1;
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
+typedef __declspec(dllexport) int typedef2;
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
+typedef int __declspec(dllexport) typedef3;
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
+typedef __declspec(dllexport) void (*FunTy)();
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
+enum __declspec(dllexport) Enum { EnumVal };
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
+struct __declspec(dllexport) Record {};
+// expected-warning@-1{{'dllexport' attribute only applies to variables and functions}}
 
 
 

clang/test/Sema/dllimport.c

@@ -4,12 +4,18 @@
 // RUN: %clang_cc1 -triple x86_64-mingw32 -fsyntax-only -fms-extensions -verify -std=c99 -DGNU %s
 
 // Invalid usage.
-__declspec(dllimport) typedef int typedef1; // expected-warning{{'dllimport' attribute only applies to variables and functions}}
-typedef __declspec(dllimport) int typedef2; // expected-warning{{'dllimport' attribute only applies to variables and functions}}
-typedef int __declspec(dllimport) typedef3; // expected-warning{{'dllimport' attribute only applies to variables and functions}}
-typedef __declspec(dllimport) void (*FunTy)(); // expected-warning{{'dllimport' attribute only applies to variables and functions}}
-enum __declspec(dllimport) Enum { EnumVal }; // expected-warning{{'dllimport' attribute only applies to variables and functions}}
-struct __declspec(dllimport) Record {}; // expected-warning{{'dllimport' attribute only applies to variables and functions}}
+__declspec(dllimport) typedef int typedef1;
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
+typedef __declspec(dllimport) int typedef2;
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
+typedef int __declspec(dllimport) typedef3;
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
+typedef __declspec(dllimport) void (*FunTy)();
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
+enum __declspec(dllimport) Enum { EnumVal };
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
+struct __declspec(dllimport) Record {};
+// expected-warning@-1{{'dllimport' attribute only applies to variables and functions}}
 
 
 

clang/test/SemaCXX/dllexport.cpp

@@ -16,13 +16,19 @@ struct External { int v; };
 
 
 // Invalid usage.
-__declspec(dllexport) typedef int typedef1; // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
-typedef __declspec(dllexport) int typedef2; // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
-typedef int __declspec(dllexport) typedef3; // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
-typedef __declspec(dllexport) void (*FunTy)(); // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
-enum __declspec(dllexport) Enum {}; // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
+__declspec(dllexport) typedef int typedef1;
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
+typedef __declspec(dllexport) int typedef2;
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
+typedef int __declspec(dllexport) typedef3;
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
+typedef __declspec(dllexport) void (*FunTy)();
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
+enum __declspec(dllexport) Enum {};
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
 #if __has_feature(cxx_strong_enums)
-  enum class __declspec(dllexport) EnumClass {}; // expected-warning{{'dllexport' attribute only applies to variables, functions and classes}}
+enum class __declspec(dllexport) EnumClass {};
+// expected-warning@-1{{'dllexport' attribute only applies to variables, functions and classes}}
 #endif
 
 

clang/test/SemaCXX/dllimport.cpp

@@ -15,13 +15,19 @@ namespace { struct Internal {}; }
 
 
 // Invalid usage.
-__declspec(dllimport) typedef int typedef1; // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
-typedef __declspec(dllimport) int typedef2; // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
-typedef int __declspec(dllimport) typedef3; // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
-typedef __declspec(dllimport) void (*FunTy)(); // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
-enum __declspec(dllimport) Enum {}; // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
+__declspec(dllimport) typedef int typedef1;
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
+typedef __declspec(dllimport) int typedef2;
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
+typedef int __declspec(dllimport) typedef3;
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
+typedef __declspec(dllimport) void (*FunTy)();
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
+enum __declspec(dllimport) Enum {};
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
 #if __has_feature(cxx_strong_enums)
-  enum class __declspec(dllimport) EnumClass {}; // expected-warning{{'dllimport' attribute only applies to variables, functions and classes}}
+enum class __declspec(dllimport) EnumClass {};
+// expected-warning@-1{{'dllimport' attribute only applies to variables, functions and classes}}
 #endif
 
 

clang/test/SemaObjC/dllexport.m

@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -triple i686-windows -fdeclspec -fsyntax-only -verify %s
+
+__declspec(dllexport) typedef int typedef1;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef __declspec(dllexport) int typedef2;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef int __declspec(dllexport) typedef3;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef __declspec(dllexport) void (*FunTy)();
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+enum __declspec(dllexport) E { Val };
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+struct __declspec(dllexport) Record {};
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, and Objective-C interfaces}}
+
+__declspec(dllexport)
+__attribute__((__objc_root_class__))
+@interface NSObject
+@end
+
+__declspec(dllexport)
+@interface I : NSObject
+- (void)method;
+@end
+
+@implementation I
+- (void)method {
+}
+@end
+

clang/test/SemaObjC/dllimport.m

@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -triple i686-windows -fdeclspec -fsyntax-only -verify %s
+
+__declspec(dllimport) typedef int typedef1;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef __declspec(dllimport) int typedef2;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef int __declspec(dllimport) typedef3;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+typedef __declspec(dllimport) void (*FunTy)();
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+enum __declspec(dllimport) E { Val };
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+struct __declspec(dllimport) Record {};
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, and Objective-C interfaces}}
+
+__declspec(dllimport)
+__attribute__((__objc_root_class__))
+@interface NSObject
+@end
+
+__declspec(dllimport)
+@interface I : NSObject
+- (void)method;
+@end
+
+@implementation I
+- (void)method {
+}
+@end
+

clang/test/SemaObjCXX/dllexport.mm

@@ -0,0 +1,33 @@
+// RUN: %clang_cc1 -triple i686-windows -fdeclspec -fsyntax-only -verify %s
+
+__declspec(dllexport) typedef int typedef1;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef __declspec(dllexport) int typedef2;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef int __declspec(dllexport) typedef3;
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef __declspec(dllexport) void (*FunTy)();
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+enum __declspec(dllexport) E { };
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+#if __has_feature(cxx_strong_enums)
+enum class __declspec(dllexport) F { };
+// expected-warning@-1{{'dllexport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+#endif
+
+__declspec(dllexport)
+__attribute__((__objc_root_class__))
+@interface NSObject
+@end
+
+__declspec(dllexport)
+@interface I : NSObject
+- (void)method;
+@end
+
+@implementation I
+- (void)method {
+}
+@end
+
+

clang/test/SemaObjCXX/dllimport.mm

@@ -0,0 +1,32 @@
+// RUN: %clang_cc1 -triple i686-windows -fdeclspec -fsyntax-only -verify %s
+
+__declspec(dllimport) typedef int typedef1;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef __declspec(dllimport) int typedef2;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef int __declspec(dllimport) typedef3;
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+typedef __declspec(dllimport) void (*FunTy)();
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+enum __declspec(dllimport) E { };
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+#if __has_feature(cxx_strong_enums)
+enum class __declspec(dllimport) F { };
+// expected-warning@-1{{'dllimport' attribute only applies to functions, variables, classes, and Objective-C interfaces}}
+#endif
+
+__declspec(dllimport)
+__attribute__((__objc_root_class__))
+@interface NSObject
+@end
+
+__declspec(dllimport)
+@interface I : NSObject
+- (void)method;
+@end
+
+@implementation I
+- (void)method {
+}
+@end
+

clang/utils/TableGen/ClangAttrEmitter.cpp

@@ -2653,6 +2653,15 @@ static std::string CalculateDiagnostic(const Record &S) {
       return "(S.getLangOpts().CPlusPlus ? ExpectedFunctionVariableOrClass : "
                                            "ExpectedVariableOrFunction)";
 
+    case Func | Var | Class | ObjCInterface:
+      return "(S.getLangOpts().CPlusPlus"
+             "     ? ((S.getLangOpts().ObjC1 || S.getLangOpts().ObjC2)"
+             "            ? ExpectedFunctionVariableClassOrObjCInterface"
+             "            : ExpectedFunctionVariableOrClass)"
+             "     : ((S.getLangOpts().ObjC1 || S.getLangOpts().ObjC2)"
+             "            ? ExpectedFunctionVariableOrObjCInterface"
+             "            : ExpectedVariableOrFunction))";
+
     case ObjCMethod | ObjCProp: return "ExpectedMethodOrProperty";
     case ObjCProtocol | ObjCInterface:
       return "ExpectedObjectiveCInterfaceOrProtocol";