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Re: better -Wuninitialized (Re: Ada files now checked in)


>
>> In tree SSA we call calculate_dominance_info and
>> compute_dominance_frontiers directly.  Also, the code uses
>> sbitmaps quite frequently.  The bitmaps are typically
>> O(n_basic_blocks).  What problem are you referring to?
>
> The bitmaps are probably sparse,
Definitely, actually.
Dominance frontiers have to be sparse.

>  and n_basic_blocks can blow up, at
> which point your memory usage blows up too.  Brad Lucier has some good
> examples of this problem.
Yes, but i'm taking care of this, so no worries.
Without ssa even enabled, the new bitmaps i'm performance tuning 
(still),  saves about 30% memory over current bitmaps.
For instance, compiling one file (I can't remember if it's expr.c or 
20001226-1.c, i forget at the moment) at -O2 normally takes 130 meg, 
peak. It now takes 100 meg, peak.
This is without modifying anything to use sparse bitmaps, just replacing 
the existing bitmap implementation.

>
> zw


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