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860078a79a
When casting a class instance to a final class, we can directly compare the isa-pointer with address of the metadata. This avoids a call to `swift_dynamicCastClass`. It also avoids a call to the metadata accessor of the class (which calls `swift_getInitializedObjCClass`). For comparing the metadata pointers it's not required that the metadata is fully initialized.
19 lines
254 B
Swift
19 lines
254 B
Swift
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public protocol P : AnyObject { }
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public class Base {
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public init() {}
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}
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public class Nonfinal : Base, P {
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public override init() {}
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}
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final public class Final : Base, P {
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public override init() {}
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}
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open class OpenBase {
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public init() {}
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}
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