(snip)
On 12/2/2008 6:34 AM, Egor Pasko wrote:
In my opinion something must be done here, or ABCD should simply be
disabled as it is otherwise crippled.
currently ABCD should be correct, but not that capable. We should
re-enable the capabilities. I am not seeing the reason to disable it
now.
Let's go this way. You try to make extra edges in InequalityGraph as I
described, if this does not work, I'll go hunting my memories and fix
it. That may imply taking your original approach. :)
I'm convinced simply adding extra edges won't work. I can try to use
the BidirectionalBubbleSort example to demonstrate why, but expect a
delay. :-)
hm, it worked earlier. The HIR changed locally, so should work
now. Your demonstration would be a really hard work.. ;
I'm confused why you think it would be hard. ABCD currently does not
eliminate the bounds checks from BidirectionalBubbleSort...
on first implementation we checked BidirectionalBubbleSort with the
current ABCD. It removed all checks. IMHO, this is a good argument to
prove that the issue is fixable without introducing principially new
concepts.
I disagree with your assessment. I believe that although ABCD did work
once, it is actually quite fragile. My fix removes a major source of
this fragility.
And as for introducing new concepts, I believe that has already happened
when you decided to introduce an e-SSA that has enhanced pi nodes and
that is used for both the upper bound and lower bound problems
simultaneously. I think those were good changes based on sound
understanding. I believe my change also falls into this category.
Please take the time to understand what I am proposing.
Naveen
