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Re: alias time explosion


> > 
> > I used the attached one with -fpermissive
> 
> 
> Thanks, i'm looking into it now.
> 

So the alias analysis time increase *is* the result of moving the
is_global_var check out of is_call_clobbered.  This is easy to fix, i'll
have a patch in a few hours.

However, there is worse news, AFAICT.


If i don't turn off scheduling entirely, this testcase now takes >10
minutes to compile (I gave up after that).

With scheduling turned off, it takes 315 seconds, checking enabled.

It looks like the scheduler is now trying to schedule some single region
with 51,000 instructions in it.

Everytime i broke into the debugger, it was busy in ready_sort re-doing
qsort on the ready-list (which probably had a ton of instructions), over
and over and over again.


I imagine the 51k instructions comes from the recent scheduling changes.
Maxim, can you please take the testcase Andrew attached earlier in the
thread, and make it so the scheduler can deal with it in a reasonable
amount of time again?  It used to take <20 seconds.

--Dan





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