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Re: [tree-ssa] DCE compile time repair.
On Fri, 2003-06-13 at 14:21, Diego Novillo wrote:
> On Fri, 2003-06-13 at 14:15, Andrew MacLeod wrote:
> > I analyzed the testfile from the POOMA library which was taking forever
> > to compile, and here's the fix.
>
> >
> Wouldn't it be better to use a sparse bitmap instead? They take a lot
> less memory than sbitmaps.
Well I figure its going to be reasonably dense.. We're checking the bit
on every basic block which has a PHI node in it... Whats the density
of that? And we'll be checking those block frequently... I see C++ code
sometimes has a lot of PHI nodes :-) So quick acess is good.
I dont think we'd notice performance either way, does a reasonably dense
sparse bitmap take less memory than an sbitmap?
Andrew