Re: [PATCH 7/8] rtc-ab-b5ze-s3: Delete an unnecessary variable in _abb5zes3_rtc_interrupt()

From: Julia Lawall
Date: Sun Jan 03 2016 - 11:59:52 EST




On Sun, 3 Jan 2016, SF Markus Elfring wrote:

> >> Pass the address of the data structure element "time" directly in calls
> >> of the function "rtc_update_irq" instead of an extra initialisation
> >> for one local variable at the beginning.
> >
> > Why is it better?
>
> I suggest to refer to the data item "rtc_data->rtc" directly because
> the variable "rtc" was read only in two if branches.
> Does it make sense then to reduce the variable allocation?

No. That is the job of the compiler. For a local variable whose address
is never taken, the compiler can easily detect its live region, and place
the initialization in an optimal way.

julia
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