RE: BUG 2.6.7 hangs on boot (rx2600)

Tian, Kevin
2004-06-24T02:57:53Z

On 6/24/2004 6:51AM, Bjorn Helgaas wrote:
>> (p6) cmp.eq p7,p6=r27,r27 <----- Should here cmp.eq.unc be used
>> instead? No time to test it now...
>
>Your change evidently solves the problem, but I don't understand
>how. Can you enlighten me? Here's the essence of the code:
>
> cmp.eq p7,p6=r25,in0
> (p6) cmp.eq p7,p6=r26,r27
> (p6) br.cond.dpnt .map
>
>As I understand it, adding ".unc" to the second cmp instruction
>should only make a difference when p6=0. In that case, after
>the old cmp (no ".unc") we'd have p6=0 and p7=1, while after
>the new cmp (with ".unc") we'd have p6=0 and p7=0. But we
>never test p7, so I don't see what difference it makes.

Ah, agree with you on this point. So maybe this touch just affects sth
behind indirectly. I'm looking into it again... Anyone has a quick
answer? :)

Thanks,
Kevin