Motorola DSP96002 - Manual (Page 575)

B-56 DSP96002 USER’S MANUAL MOTOROLA
Unsigned 32 Bit Integer
Program ICycles
Division of d0 = d0/d2 Words
eor d1,d1 ; clear d1
do #32,dloop ;32 quotient bits 2 3
rol d0 ;dividend bit out, q bit in 1 1
rol d1 ;put in temp 1 1
cmp d2,d1 ;check for q bit 1 1
sub d2,d1 ifcc ;update if less 1 1
dloop
rol d0 ;last q bit 1 1
not d0 ;complement q bits 1 1
--- ---
Totals: 8 133
The final remainder is not produced. This program may calculate only the number of quotient bits required
and has variable execution time.
Unsigned 32 Bit Integer
Division of d0 = d0/d1, d0>=d1
cmp d1,d0 d0.l,d2.m
eor d0,d0 iflo
jlo divdone ; divisor > dividend
bfind d0,d0 d3.l,d8.l
jmi dive2big ;dividend has
;32 significant bits
bfind d1,d2 d0.h,d0.l ;find # of quotient bits
movei #32,d3
move d2.h,d2.l
sub d0,d2 d2.m,d0.l
inc d2 d2.l,d2.h ;compute loop iteration count
sub d2,d3
lsl d2,d1 d3.l,d2.h ;align divisor
do d2.l,divloop_fast
cmp d1,d0 ;perform test subtract
sub d1,d0 ifhs ;if no borrow, do subtract
rol d0 ;mult remx2, save quo. bit (borrow)
divloop_fast
not d0 d8.l,d3.l ;flip inverted quotient
lsl d2,d0 ;clean off any remainder
lsr d2,d0
jmp divdone ;done