Bob Blick wrote:

|Hi Everyone,
|
|Usually I don't pay any attention to optimizing code, if it works I use
|it, but this morning I'm feeling picky. No where in my notes do I have
a
|decrement for more than a 2 byte number. I want 3 bytes. This is what I
|came up with. It looks stupid to me. Feel free to come up with
something
|better.  It's for midrange pics and does not use any temporary
registers.
|
|movlw 1
|subwf low,f
|movlw 0
|SKPC
|movlw 1
|subwf mid,f
|SKPC
|decf hi,f
|
|Any improvements on this?
|
|Thanks,
|Bob

A simple improvement is to use the 1 which is already loaded in W to
eliminate the second "movlw 1" instruction:

movlw 1
subwf low,f
SKPNC
movlw 0
subwf mid,f
SKPC
decf hi,f

Another alternative which cost 1 more ROM word and 1 extra cycle worst
case, but saves 2 clocks 255/256 times, and does not modify W register
would be:
    movf Low,f
    bnz X
    movf Mid,f
    skpnz
        decf High,f
    decf Mid,f
X   decf Low,f

Chip Weller