Re: RFA: frame id enhancement

[Kevin Buettner <kevinb at redhat dot com>]

On Oct 16,  5:49pm, J. Johnston wrote:

> It "is" a register stack on the ia64.  Registers r32 - r127 for any frame all 
> come from this area.  It gets bumped up by a special alloc() instruction.  I'm 
> not sure I would call it unordered.  It may be better to say that it is treated 
> as unordered.  That would make the comments below much simpler - i.e. the 
> special_addr field is treated as unordered so it is never used to determine 
> order when comparing frames.

For IA-64, the backing store most certainly is ordered.  It is quite
possible to have a bunch of consecutive frames which all have the same
"sp" value.  For these frames, older frames will have smaller bsp values
than newer frames.  (I.e, the backing store stack grows from lower
addresses toward higher addresses.)