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From: "a dot kaiser at gmx dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/19154] miss-optimization of (x & pow2C) avr conditionals returning bool equivalent values
Date: Thu, 29 May 2008 17:02:00 -0000	[thread overview]
Message-ID: <20080529170205.24917.qmail@sourceware.org> (raw)
In-Reply-To: <bug-19154-9497@http.gcc.gnu.org/bugzilla/>



------- Comment #6 from a dot kaiser at gmx dot net  2008-05-29 17:01 -------
In a similar case I've got the impression that the ifcombine pass might be
responsible for rewriting the "if" into shift and mask. It is rather
questionable whether this really optimizes things for simple targets which jump
faster as they can shift.

I am suprised however, that many optimization strategies can be disabled by
some -fxxx option, but not this one. A first and probably simple approach could
be, to just add such an option.


-- 

a dot kaiser at gmx dot net changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |a dot kaiser at gmx dot net


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19154


       reply	other threads:[~2008-05-29 17:02 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-19154-9497@http.gcc.gnu.org/bugzilla/>
2008-05-29 17:02 ` a dot kaiser at gmx dot net [this message]
2009-10-24 15:37 ` hutchinsonandy at gcc dot gnu dot org
2009-10-24 15:40 ` hutchinsonandy at gcc dot gnu dot org
2009-12-30 16:15 ` hutchinsonandy at gcc dot gnu dot org
2010-01-29 17:12 ` eric dot weddington at atmel dot com
     [not found] <bug-19154-4@http.gcc.gnu.org/bugzilla/>
2014-02-16 13:15 ` jackie.rosen at hushmail dot com
2004-12-25 20:21 [Bug c/19154] New: " schlie at comcast dot net
2004-12-25 20:34 ` [Bug middle-end/19154] " pinskia at gcc dot gnu dot org
2004-12-25 20:53 ` pinskia at gcc dot gnu dot org
2004-12-25 20:57 ` pinskia at gcc dot gnu dot org
2004-12-25 21:39 ` schlie at comcast dot net
2004-12-25 21:57 ` schlie at comcast dot net

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