[ObjC] Encode type arguments in property information string constants

[arphaman]

Summary

This patch ensures that Objective-C type arguments are included in the string constants that have encoded information about @property declarations.

[ahatanak]

Do you know whether this patch would have any effect on the objective-c runtime? I suspect it wouldn't cause the runtime to crash, but I don't know how the runtime uses the encoded type information.

Other than that, the changes made in this patch look good to me.

[gparker42]

This won't work. The property attribute string consists of comma-separated fields. The encoding used here embeds commas into the type value, which will break parsing of the attribute string. You'll need to use a separator other than a comma.

lib/AST/ASTContext.cpp

 #include "clang/AST/MangleNumberingContext.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/AST/VTableBuilder.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Support/Capacity.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
 #include <map>
 
 using namespace clang;
if (!EncodingProperty &&
       return;
     }
 
     S += '@';
     if (OPT->getInterfaceDecl() && 
         (FD || EncodingProperty || EncodeClassNames)) {
       S += '"';
       S += OPT->getInterfaceDecl()->getObjCRuntimeNameAsString();
+      ArrayRef<QualType> TypeArgs = OPT->getTypeArgs();
+      if (!TypeArgs.empty()) {
+        S += '<';
+        for (const auto &I : llvm::enumerate(TypeArgs)) {
+          if (I.Index)
+            S += ',';
+          getObjCEncodingForTypeImpl(I.Value, S, ExpandPointedToStructures,
+                                     ExpandStructures, nullptr, false,
+                                     EncodingProperty);
+        }
+        S += '>';
+      }
       for (const auto *I : OPT->quals()) {
         S += '<';
         S += I->getObjCRuntimeNameAsString();
         S += '>';
       }
       S += '"';
     }
     return;

test/CodeGenObjC/objc2-property-encode.m

 // RUN: %clang_cc1 -triple=i686-apple-darwin9 -emit-llvm -o %t %s
 // RUN: grep -e "T@\\\\22NSString\\\\22" %t
+// RUN: FileCheck %s -input-file=%t
 @interface NSString @end
 
 typedef NSString StoreVersionID ;
 
 @interface Parent 
   @property(retain) StoreVersionID* foo;
 @end
 
 @implementation Parent
 @dynamic foo;
 @end
+
+// rdar://22496485
+@interface TypeParameters<__covariant ObjectType>
+
+@end
+
+@interface TypeParameters2<__covariant A, __covariant B>
+
+@end
+
+@protocol MyProtocol;
+@class MyClass;
+
+@interface Bar
+
+@property(copy) TypeParameters<MyClass*> *p1;
+
+@property(copy) TypeParameters2<MyClass*, MyClass*><MyProtocol> *p2;
+
+@end
+
+@implementation Bar
+
+@end
+
+// CHECK: @OBJC_PROP_NAME_ATTR_{{.*}} = {{.*}} c"T@\22TypeParameters<@\22MyClass\22>\22,C,V_p1\00"
+// CHECK: @OBJC_PROP_NAME_ATTR_{{.*}} = {{.*}} c"T@\22TypeParameters2<@\22MyClass\22,@\22MyClass\22><MyProtocol>\22,C,V_p2\00"