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Re: List of simplifications we should perform




On 11 May 2001, Andi Kleen wrote:

> Daniel Berlin <dan@www.cgsoftware.com> writes:
>
> If this is supposed to be C...
>
> > Simplifications for ~ and !:
> >
> >    ! ! j			j
>
> !!j is not j, it is j?1:0.
>
That's what I thought, but SGI's compiler quite clearly disagrees.
It just says:

if (<it's of the form ! ! j>)
	delete the not's.

It performs this at all optimization levels, too.

--Dan


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