Re: can: ucan: Use usb_endpoint_type() rather than duplicating its implementation

[Vincent Mailhol]

On 26/06/2025 at 16:22, Markus Elfring wrote:
>>> I am unsure if the check reordering would be desirable for this function implementation.
>>
>> Ah, you want to confirm whether
>>
>>   usb_endpoint_dir_in(ep) && usb_endpoint_xfer_bulk(ep)
>>
>> is the same as
>>
>>   usb_endpoint_xfer_bulk(ep) && usb_endpoint_dir_in(ep)
>>
>> ?
> 
> Exactly, yes.
> 
> Commutativity can probably be applied in this case.
> But the different execution order will influence the corresponding run time characteristics.
> https://en.wikipedia.org/wiki/Short-circuit_evaluation
> https://en.wikipedia.org/wiki/Commutative_property
> 
> The data processing order from known API function implementations might get priority
> also at discussed source code places in the near future.

Yes. This is what I tried to explain in my previous message: that the short
circuit evaluation may impact the result when there is an undefined behaviour
but that it is not the case here.


Yours sincerely,
Vincent Mailhol