Re: [KERNEL]: Avoid divide in IS_ALIGN

[Andreas Schwab]

"linux-os (Dick Johnson)" <linux-os@xxxxxxxxxxxx> writes:

> Executing this script.............
>
> cat <<EOF >/tmp/xxx.c
> #include <stdio.h>
>
> #define IS_ALIGNED(x,a)		(((x) % ((typeof(x))(a))) == 0)
> #define _IS_ALIGNED(x, a)	(((x) & ((typeof(x))(a) - 1)) == 0)
>
> int main()
> {
>     int i;
>     long p = 0x12345678;
>     for(i=1; i< 0x11; i++)
>         printf("Old = %d, new = %d\n", IS_ALIGNED(p, i), _IS_ALIGNED(p, i));

Alignment is only defined for powers of two.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@xxxxxxx
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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