On Fri, 13 Dec 1996 04:12:02 +0100 
 Guenther Grau <s_grau@ira.uka.de> wrote:

 > Hmm, if you really want to microoptimize, I guess you'll have to write
 > a version for each cpu we support and use the usual tricks to test for
 > the cpu just once, preferably during boot and after that just use the
 > functions without having to test for the cpu over and over again.

A much better approach is to gave a single function that does the
comparisons only if configured for multiple CPU variants.  If only
configured for one, the comparisons aren't there (they're #ifdef'd).

This eliminates unnecessary code size and overhead from indirect
function calls in the critical path.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
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