[FFmpeg-cvslog] r13277 - trunk/libavcodec/ra144.c

[Michael Niedermayer]

On Sat, May 24, 2008 at 01:11:14PM +0200, Vitor Sessak wrote:
> Michael Niedermayer wrote:
> > On Sat, May 24, 2008 at 11:20:09AM +0200, vitor wrote:
> >> Author: vitor
> >> Date: Sat May 24 11:20:09 2008
> >> New Revision: 13277
> >>
> >> Log:
> >> Simplify final()
> > [...]
> >> -        x = ptr[10] - sum;
> > [...]
> >>  
> >> -        if (x<-32768 || x>32767) {
> >> +        if (ptr[10] - sum < -32768 || ptr[10] - sum > 32767) {
> > [...]
> >> -        ptr[10] = x;
> >> +        ptr[10] -= sum;
> > 
> > I would not call that part simplification.
> 
> Why? I found that adding a auxiliary var just to simplify an if 
> obfuscate the code (it's harder to see that with no overflow, this code 
> just do ptr[10] -= sum)...

3 redundant subtractions ...
of course x is a bad name
new_val would be better

also

if(new_val + 32768U > 65537U)
might be faster ...


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

There will always be a question for which you do not know the correct awnser.
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