Re: CRC was: Re: beta testing version

On Fri, Dec 08, 2000 at 10:36:39AM -0800, Ian Lance Taylor wrote:
> Incidentally, I benchmarked the previously mentioned 64-bit fingerprint,
> the standard 32-bit CRC, MD5 and SHA, and the fastest algorithm on my
> Celeron and on a PIII was MD5. The 64-bit fingerprint was only a hair
> slower, the CRC was (quite surprisingly) about 40% slower, and the
> implementation of SHA that I had available was a real dog. Taking an
> arbitrary 32 bits of a MD5 would likely be less collision prone than
> using a 32-bit CRC, and it appears faster as well.
>
> I just want to confirm that you used something like the fast 32-bit
> CRC algorithm, appended. The one posted earlier was accurate but
> slow.

Yes. I just rebuilt the framework using this exact code, and it
performed identically to the previous CRC code (which didn't have an
unrolled inner loop). These were compiled with -O6 with egcs 1.1.2.
--
Bruce Guenter <bruceg(at)em(dot)ca> http://em.ca/~bruceg/