Cool! This is like... mail or something!
Once upon a time (Thursday, March 27, 1997 to be precise), Tom Torfs wrote a 
letter to Flemming Sondergaard about "Extra Space."...
 NC>> Ok, what are REP MOVSW instructions?
 FS>> High-level functions which you should never use for anything unless
 FS>> you need to create a compact routine rather than a fast one.
 TT> AFAIK, REP MOVSW is still the fastest way to move blocks from memory to
 TT> memory (even faster than DMA). REP MOVSD is still faster, of course
 TT> (provided you have a 32-bit databus).
I once compared REP MOVSD to this method:
loop_000:
         mov       eax,ds:[si]
         add       si,4
         mov       es:[di],eax
         add       di,4
         dec       cx
         jnz       loop_000
And REP MOVSD _was_ the slowest of the two. Just like
         loop      label
is slower than
         dec       cx
         jnz       label
 ___,/|
 \ o_O|    - Flemming Sondergaard
 =(_|_)=
    U
--- Terminate 4.00/Pro
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