cc -O2
DES_LONG is 'unsigned int'

options    des ecb/s
 4 r2 p    181146.14 100.0%
16 r2 p    172102.94  95.0%
 4 r2 i    165424.11  91.3%
16  c p    160468.64  88.6%
 4  c p    156653.59  86.5%
 4  c i    155245.18  85.7%
 4 r1 p    154729.68  85.4%
16 r2 i    154137.69  85.1%
16 r1 p    152357.96  84.1%
16  c i    148743.91  82.1%
 4 r1 i    146695.59  81.0%
16 r1 i    144961.00  80.0%
-DDES_RISC2 -DDES_PTR