Re: [KJ][RFC][PATCH] BIT macro cleanup

From: Richard Knutsson
Date: Fri Feb 23 2007 - 09:11:31 EST

Milind Choudhary wrote:
On 2/23/07, Richard Knutsson <ricknu-0@xxxxxxxxxxxxxx> wrote:
> +#define BITWRAP(nr) (1UL << ((nr) % BITS_PER_LONG))
> & make the whole input subsystem use it
> The change is huge, more than 125 files using input.h
> & almost all use the BIT macro.
It is as a big of change, but have you dismissed the "BIT(nr %
BITS_PER_LONG)" approach?

but just looking at the number of places it is being used,
it seems that adding a new macro would be good
which makes it look short n sweet
You have a point there but I still don't think it should be in bitops.h. Why should we favor long-wrap before byte-wrap, so what do you think about doing:

#define BITWRAP(x) BIT((x) % BITS_PER_LONG)

in input.h? Otherwise I think it should be call LBITWRAP (or something) to both show what kind it is and enable us to add others later.
> -#define BIT(i) (1UL << ((i)&(__NFDBITS-1)))
Are you sure you can just delete this one? users in this file
> -#define BIT(x) (1ul<<(x))
> #define POW2(x) (1ul<<(x))
Maybe you can clean up POW2 as well (or define it as "#define POW2(x)
but want to go one step at a time
currently just cleaning up places where BIT macro is explicitly defined
the implicit uses [replacing 1UL << (x)] will be handled in another patch series
"use BIT macro wherever appropriate"
Sounds good

Also, it seems your mail-client swapped the tabs to spaces (aka not able
to apply).
attaching the patch file
bear with me for the time being

No problem :)
It is of course always a good idea to send the patches to yourself and then trying to apply that patch to see it is alright. But sometimes you can't get the mailer working, then sendpatchset can be of interest:

Richard Knutsson

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