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Re: Missing if optimization
- From: James E Wilson <wilson at specifixinc dot com>
- To: Uros Bizjak <uros at kss-loka dot si>
- Cc: gcc at gcc dot gnu dot org
- Date: Thu, 09 Sep 2004 15:10:36 -0700
- Subject: Re: Missing if optimization
- References: <413FE7D1.8000201@kss-loka.si>
Uros Bizjak wrote:
The if optimization, which produces quite optimized code for integer
case is missing for floatin-point compares.
This is very target dependent, and you didn't mention the target. From
the assembly code, it appears to be x86.
Some targets have comparisons that can be used to optimize this
testcase. Some don't.
For those that do, whether it gets optimized depends on how the backend
represents compares, which is done differently for different targets.
As for the optimization itself, there should be no problem there, as has
already been pointed out we get this right for powerpc.
You might consider filing a bug report for the missed optimization if
you haven't already.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com