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Re: [PATCH] Overhaul __builtin_constant_p processing


> > Your patch causes gcse.c:find_avail_set to loop forever on x86 at -O2.
> > I haven't analysed why it's looping yet.
> 
> This bug is PR opt/8492, present on 3.3 branch and mainline. The local cprop 
> pass is allowed to cprop into condjumps, hence to modify the CFG. But the 
> latter is not cleaned up before the global cprop pass, which confuses the 
> LCM code. See the analysis referenced in the audit trail.

Oops, I assumed that this is fixed by the Roger's changes, but for 3.3
it is still present.  I will go to fix it now.

Honza
> 
> -- 
> Eric Botcazou


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