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Re: [PATCH] Optimize "a || b" into "(a | b) != 0"

From: Jan Hubicka <jh at suse dot cz>
To: Roger Sayle <roger at eyesopen dot com>
Cc: Jan Hubicka <jh at suse dot cz>, gcc-patches at gcc dot gnu dot org
Date: Sat, 18 May 2002 17:11:05 +0200
Subject: Re: [PATCH] Optimize "a || b" into "(a | b) != 0"
References: <20020518143716.GB22633@atrey.karlin.mff.cuni.cz> <Pine.LNX.4.33.0205180845540.24829-100000@www.eyesopen.com>

> 
> 
> > Hmm, this is interesting.  How long is GCC doing this transfromation?
> > 2.95.3 certainly not at least in my simple testcase.
> 
> Don't forget "-mbranch-cost=2" on IA-32.  As you've hinted previously,
> this transformation should be/is dependent upon the target's branch cost.
> To answer your question, "cvs annotate" reports 11th August 1997, but
> the actual code could be much older.

Thanks for enlightening me.  I never noticed this code previously.  I have
nothing against your patch then. :)

Honza
> 
> Roger
> --

References:
- Re: [PATCH] Optimize "a || b" into "(a | b) != 0"
  - From: Jan Hubicka
- Re: [PATCH] Optimize "a || b" into "(a | b) != 0"
  - From: Roger Sayle

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