[Qemu-devel] What do these instructions do??

[Davide]

In target-i386/translate.c there are this instructions:
int op, f, val;
op = (b >> 3) & 7;
f = (b >> 1) & 3;
if ((b & 1) == 0)
   ot = OT_BYTE;
else
   ot = dflag + OT_WORD;
What does this code do??