24ae22c047
The objc_runtime_visible attribute deals with an odd corner case where a particular Objective-C class is known to the Objective-C runtime (and, therefore, accessible by name) but its symbol has been hidden for some reason. For such classes, teach CodeGen to use objc_lookUpClass to retrieve the Class object, rather than referencing the class symbol directly. Classes annotated with objc_runtime_visible have two major limitations that fall out from places where Objective-C metadata needs to refer to the class (or metaclass) symbol directly: * One cannot implement a subclass of an objc_runtime_visible class. * One cannot implement a category on an objc_runtime_visible class. Implements rdar://problem/25494092. llvm-svn: 265201
20 lines
688 B
Objective-C
20 lines
688 B
Objective-C
// RUN: %clang_cc1 -triple x86_64-apple-darwin -fobjc-runtime=macosx-10.9.0 -emit-llvm %s -o - | FileCheck %s
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// RUN: %clang_cc1 -triple i386-apple-darwin -fobjc-runtime=macosx-fragile-10.9.0 -emit-llvm %s -o - | FileCheck %s
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@interface Root
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+(Class)class;
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@end
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__attribute__((objc_runtime_visible))
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__attribute__((objc_runtime_name("MyRuntimeVisibleClass")))
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@interface A : Root
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@end
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// CHECK: [[CLASSNAME:@.*]] = private unnamed_addr constant [22 x i8] c"MyRuntimeVisibleClass
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// CHECK: define i8* @getClass() #0 {
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Class getClass(void) {
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// CHECK: call i8* @objc_lookUpClass(i8* getelementptr inbounds ([22 x i8], [22 x i8]* [[CLASSNAME]], i32 0, i32 0)) #2
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return [A class];
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}
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