28 Sep
2009
28 Sep
'09
9:09 a.m.
On Sat, 2009-09-26 at 04:20 +0100, Brandon S. Allbery KF8NH wrote:
On Sep 25, 2009, at 07:54 , Duncan Coutts wrote:
pessimistic. We could do better on machines that are tolerant of misaligned memory accesses such as x86. We'd need to use cpp to switch
Hm. I thought x86 could be tolerant (depending on a cpu configuration bit) but the result was so slow that it wasn't worth it?
It's slow and you would not want to do it much, however I think it's still comparable in speed to doing a series of byte reads/writes and using bit twiddling to convert to/from the larger word type. It's probably also faster to do an unaliged operation sometimes than to do an alignment test each time and call a special unaliged version. Duncan