memcpy testing

Seems we aren't the only ones concerned about memset-like optimizations:

http://www.bsdforums.org/forums/showthread.php?threadid=3778

This talks about using MMX assembly instructions for memcpy.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073