lea         multiply_d7,a0 ; fast integer multiply table for d7
move.l      d6,d7       ; e.g. A000A000 from $28E7A2
lsr.l       #8,d7       ; 00A000A0
neg.w       d7          ; FF5F6000
addi.w      #$80,d7 ; 'Ç' ; FF5F6080
swap        d4          ; e.g. $17 -> $170000
move.w      d3,d4       ; e.g. d3=$38E0 => d4=$1738E0
andi.w      #$1FF,d4    ; d4=$1700E0
lsr.w       #1,d4       ; d4=$B1070
adda.w      d4,a0       ; OK, IKD, you got me. wtf?