Subject: DDB single stepping works
To: None <port-ia64@netbsd.org>
From: Cherry G. Mathew <cherry@mahiti.org>
List: port-ia64
Date: 12/22/2005 17:08:24
Hi,

You can now single step with the debugger, but setting breakpoints
triggers the single stepping anyway.... I could do with some tips on why
this happens.


Quick note on debugger addressess:

Itanium uses 'Bundles' ie; VLIW instructions of 128 bits.

Therefore, for every address on a 128 bit ( 16byte ) boundary points to
the first instruction or 'slot0'. Since further slots are not on word
aligned boundaries, a fictitious address of addr + slotno is allowed,
which implicitly allows breakpointing at a given slot within an ia64
VLIW bundle. This is the exact same way that FreeBSD does things.

I've checked in the code to CVS in any case, so I'm going to start
focusing on getting pmap to work now.

Thanks,

Cherry.