Re: [Valgrind-developers] valgrind: r10940 - in branches/ARM/coregrind: . m_debuginfo

[Tom H. <to...@co...>]

On 13/11/09 18:08, Julian Seward wrote:

>> This is also I think the main problem that Jakub was having with PPC of
>> it not unwinding enough registers and it not being easy to add extra
>> registers to the set being unwound.
>
> Uh, so we're trying to support CFI unwinding on PPC too, now?  This
> seems like a good thing to me.  However, I've been scratching my head,
> trying to figure out how to generalise the type DiCfSI (the unwind
> summary record) and VG_(use_CF_info) (the function that uses it)
> so as to be more general, yet not more expensive in time or space.
> For a large program, there are zillions of DiCfSI records sloshing
> around, and looking them up causes noticable L2 misses.

Jakub tried to get CFI unwinding working and gave up - he talks about it 
on one of the bugs. There are a few bits of the work he did in the 
patches I committed but most of it he reverted and just fixed up that 
one unwind bug in the traditional unwinder.

Tom

-- 
Tom Hughes (to...@co...)
http://www.compton.nu/