> On Jun 23, 2016, at 1:48 PM, Slava Pestov <[email protected]> wrote:
>
>
>> On Jun 23, 2016, at 1:46 PM, Andrew Trick <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>>
>>> On Jun 23, 2016, at 12:53 PM, Slava Pestov via swift-evolution
>>> <[email protected] <mailto:[email protected]>> wrote:
>>>
>>> The proposal is to change the type of self to always be Self, which can be
>>> thought of as a special generic type parameter bound to the dynamic type of
>>> the instance.
>>
>> We’re currently specializing functions that take `self` as an argument. I
>> don’t think that will be possible after your proposed change.
>>
>> - Andy
>
> I’m not sure what that means. Do you currently punt on certain optimizations
> if a method returns ‘Self’?
>
> It should be possible to keep the reified type information around, by passing
> in a metatype or something for example. Can you give a concrete code snippet
> demonstrating the optimization and how this change would inhibit it?
We bail out of generic specialization, inlining, and function signature
specialization when a type substitution contains dynamic self.
(hasDynamicSelfTypes). So, yes we currently almost entirely punt on
optimization for methods that return Self.
I don’t have an interesting case to point out. You can look into any trivial
example:
func foo<T>(_: T) {}
func method() {
foo(self)
}
-Andy
_______________________________________________
swift-evolution mailing list
[email protected]
https://lists.swift.org/mailman/listinfo/swift-evolution
