Re: New inventions in rounding up in catc.c?

[Denis Vlasenko]

On Saturday 24 September 2005 21:46, Grant Coady wrote:
> On Sat, 24 Sep 2005 13:43:42 +0300, Denis Vlasenko <vda@xxxxxxxxxxxxx> wrote:
> > 		/* F5U011 only does one packet per RX */
> > 		if (catc->is_f5u011)
> > 			break;
> >-		pkt_start += (((pkt_len + 1) >> 6) + 1) << 6;
> >+		pkt_start += ((pkt_len + 2) + 63) & ~63;
> 
>   		pkt_start += ((pkt_len + 1) + 64) & ~63;
> 
> Seems more clear to me.

Why?

((pkt_len + 2) + 63) & ~63 is "add 2 and round up to next 64".
((pkt_len + 1) + 64) & ~63 is "???!"

It's strange code anyway, I hope maintainer can clarify what's going on.
(I suspect it was intended to be pkt_len - 1, not +, in the first place)
--
vda
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