On Thu, 8 Jul 2004, Sridhar Adagada wrote:
> As you can see $6 is the length, my confusion is at the lines 12-14,
> 19, 20 why is the length added with 65535 and the comparison with 0
It's not `added with 65535', but `ANDed with 65535'. MIPS32 has 32-bit integer
operations only. If you want to do 16-bit math, all data has to be masked.
Anyway, for performance, it's better to do 32-bit math only.
> short cal_xxx(short *abs, short *coef, short len, short base)
> {
> short i;
> short sum = 0;
>
> for (i = 0; i < length; i++)
> {
> sum += ( (unsigned int)abs[i] * (unsigned int)coef[i] );
Why cast to unsigned int while sum is a short? Unless you really want to rely
on sum being a short, you better make it int and do the truncation to short
after the loop.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
