IMA vs tree-ssa

[Dale Johannesen]

On Mar 8, 2004, at 2:32 PM, Mark Mitchell wrote:
> Dale Johannesen wrote:
>> This bit seems to be working, but doesn't solve the entire problem by 
>> any means.
>> The tree-based aliasing and structure-scalarizing code also think 
>> there's only
>> one copy of a struct type node, and work off pointers.   There may be 
>> more places
>> I haven't found yet; can you think of any?  (Most of the SPEC 
>> failures seem to be
>> due to aliasing; it thinks different copies of a struct from 
>> different files do not
>> alias, when in fact they do.  This breaks lots of things.)
>>
> I believe that we should not hold up the tree-ssa merge for IMA.
>
> Instead, we should just let IMA be broken for a while.

That's a regression.  Just pointing it out.

I don't mind not making it be a requirement, provided patches that fix 
these problems
are still eligible despite the freeze.   (I have made some progress, 
including fixes for
both the points I listed above.  Perhaps there is enough that I should 
prepare a patch,
but there are still problems.)

> It's a new feature, not one that people have gotten used to at this 
> point.
> It's a valuable optimization, but it's a problem, we should move on 
> without it and then add it back later.
>
> That's my opinion, not an official SC position by any means.