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Re: Use assert()s for optimization?


Richard Guenther <rguenth@tat.physik.uni-tuebingen.de> writes:

> Is there a way to turn an assert() into optimization hints for gcc?
> Like in
> 
> double mysqrt(double x)
> {
>   assert(x >= 0.0);
>   return sqrt(x);
> }

Interestingly, Toon Moene just asked for the same thing on gcc-patches :)
I don't think it's currently possible. Maybe we could have
something similar to Microsoft's __assume(), which would then feed the
nonnegative_p etc. functions and the VRP to come. I'm not sure how to
represent it best in the intermediary representation, though.

-- 
	Falk


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