# [virtmach] instruction set

**Dennis Yelle**
dennis51@jps.net

*Tue, 18 Apr 2000 09:33:58 -0700*

thaddaeus.frogley@creaturelabs.com wrote:
>*
*>* Hi,
*>*
*>* Quick question. Don't feel obliged to justify your answer.
*>*
*>* When trying to create an instruction set for a 3 address machine, assuming
*>* that the following already exist:
*>*
*>* jump target
*>* jump-if-zero a,target
*>* jump-if-non-zero a,target
*
Well, assuming I already have:
subtract a,b,c
jump-if-negative a, target
And assuming I am short of op code space,
I don't need any of these:
>* jump-if-equal a,b,target
*>* jump-if-less a,b,target
*>* test-if-equal a,b,result
*>* test-if-less a,b,result
*