From: "Henrik Mannerström" <henrik.mannerstrom@helsinki.fi>
To: gcc-help@gcc.gnu.org
Subject: Re: Removing bound checks from a switch statement
Date: Thu, 18 Feb 2010 16:32:00 -0000 [thread overview]
Message-ID: <20100218173832.12491s2bi11hzsag@webmail.helsinki.fi> (raw)
In-Reply-To: <87sk8ywqvd.fsf@falma.de>
Quoting "Christoph Groth" <cwg@falma.de>:
> I do not know how to solve the problem you described, but another way of
> speeding up a switch statement might be using the GCC extension "Labels
> as Values".
>
> http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html
Thank you very much! This was exactly what I was looking for.
I made a completely non-standard, spaghettisized version of the
program and luckily it did not run any faster than the switch-based
one, so I can stick to my -ansi option. The earlier reported speedup
was probably just an outlier in the performance test.
Many thanks! Now I can put this behind me and work on other aspects.
Henrik
next prev parent reply other threads:[~2010-02-18 15:38 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-17 14:22 Henrik Mannerström
2010-02-18 14:44 ` Christoph Groth
2010-02-18 16:32 ` Henrik Mannerström [this message]
2010-02-17 18:11 Henrik Mannerström
2010-02-17 19:00 ` Jeff Law
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