> BTW which checksum algorithm did base your
> assembly code on?  Does anyone know which of the checksum algorithms is the
> fastest?

Unfortunately, that depends largely on your platform. The best thing to do is 
to try all of them: call them in a loop on a data buffer that is bigger than 
your caches and see which one finishes first.

> I'm a little surprised that other than the call overhead that an
> assembly version of memcpy is much faster than what the complier produces 
> from the library?

The difference here is not C or assembly but 'standard' library (written in C, 
used on many platforms) or hand-written code that performs well on your 
specific platform. And let me tell you there *is* room for improvement here. 
For example, some C libraries use byte-by-byte copy if compiled with the 
'wrong' options... Nevertheless, the standard library often is not too bad when 
copying a well-aligned source to a well-aligned destination.

Simon
-- 
Neu: GMX FreeDSL Komplettanschluss mit DSL 6.000 Flatrate + Telefonanschluss 
für nur 17,95 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


_______________________________________________
lwip-users mailing list
[email protected]
http://lists.nongnu.org/mailman/listinfo/lwip-users

Reply via email to