RFA: frame id enhancement

[J. Johnston]

Kevin Buettner wrote:
> 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.)
> 

Just to clarify, I was referring to two different "it"s above.  What I meant to 
say was "I wouldn't call the special field unordered".  Sorry for the confusion. 
  The special field may or may not be an ordered value, but generically, it 
should be treated as unordered which is why I made the clarification in the comment.

-- Jeff J.