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Re: List of simplifications we should perform
- To: Andi Kleen <ak at suse dot de>
- Subject: Re: List of simplifications we should perform
- From: Daniel Berlin <dan at www dot cgsoftware dot com>
- Date: Fri, 11 May 2001 07:42:38 -0400 (EDT)
- cc: <gcc at gcc dot gnu dot org>
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