One Instruction Set Computer

An one instruction set computer $($OISC$)$ is an extreme form of a RISC ISA $$ it has only $1$ instruction. In this question, consider one such machine called SUBLEQ. A SUBLEQ machine has exactly one instruction that $$subtracts and branches if less than or equal to zero$($called subleq$)$:

subleq a$,$ b$,$ c

A subleq instruction has $3$ operands, a$,$ b and c$,$ which are all memory addresses. It has the following

semantic:

memory$[$b$]=$ memory$[$b$]-$ memory$[$a$]$

if $($memory$[$b$]<=0)$ goto c

A$\mathrm{.}5\mathrm{.}1$ Based on the $3$ terms of the Iron Law: $($i$)$ instruction per program $($ii$)$ cycle per instruction $($iii$)$ cycle time, compare the relative performance between the SUB