Efficient 68000
Volume Number: 8
Issue Number: 2
Column Tag: Assembly workshop
Efficient 68000 Programming
If a new CPU speeds up inefficient code, what do you think it will do to
efficient code?
By Mike Scanlin, MacTutor Regular Contributing Author
The dew is cold. It is quiet. I hear nothing except for crackling sounds coming
from the little fire burning two inches to the left of my keyboard. It wasn’t there a
minute ago. Seems that Doo-Dah, the god of efficient programming, is upset with me for
typing “Adda.W #10,A0” and just sent me a warning in the form of a lightning bolt. I
hate it when he does that. You’d think that after three years in his service, re searching
which 68000 assembly language instructions are the most efficient ones for any given
job, that he would lighten up a little. I guess that’s what makes him a god and me a mere
mortal striving for enlightenment through the use of optimal instructions. As I
extinguish the fire with a little Mountain Dew, I reflect upon the last three years.
My first lesson in the service of Doo-Dah was that proficiency in assembly
language is a desirable skill in programmers so long as performance is a desirable
attribute of software. The nay-sayers who depend upon faster and faster CPUs to make
their sluggish software run at acceptable speeds don’t realize the underlying
relativeness of the universe. If a new CPU will speed up a set of non-optimal